the purpose of this statewide dredging policy …...the purpose of this statewide dredging policy...

The purpose of this Statewide Dredging Policy Framework is to improve consistencyand coordination in the design and review process for dredging projects in Delawarewaters. It will ensure that the State’s concerns regarding environmental protection,economic value, and stewardship of Delaware’s natural, commercial, andrecreational resources are addressed.

This document is designed to be a resource for permit applicants and those reviewingapplications. It presents the regulations and design and operations standards aimedat ensuring that necessary projects will have minimal environmental impacts andwill comply with State Water Quality Standards and other requirements. However,this document is to be used only as a guideline, and applicants should be sure todiscuss their individual projects with State and Federal agencies as necessary.

Another purpose of this document is to provide education for those interested indredging projects from the perspective of an affected public citizen. The authorshave attempted to reduce the amount of “technical” language where possible. Italso provides an overview of the permit process so that interested citizens can takeadvantage of opportunities for public input and participation.

This document was developed as a result of the coordination and dedication of theDelaware Dredging Working Group, made up of stakeholders representing projectapplicants, permit review agencies, environmental groups, and public citizens. Alist of participants can be found in the Appendices.

The Delaware Statewide Dredging Policy Framework contains backgroundinformation about dredging in general, existing regulations and guidance fromfederal and state agencies, and supporting information for many key dredging issues.

In developing this document, the Working Group decided to address only navigationprojects and beach nourishment in tidal waters. This Policy Framework will notaddress policies for tax ditches, drainage projects, or freshwater pond dredging.While the latter three are all important project types, they have unique issues whichrequire specialized attention.

For more information on this document, please contact:

David Carter or Susan LoveDelaware Coastal Programs

Department of Natural Resources and Environmental Control89 Kings HighwayDover, DE 19901

Phone: (302) 739-3451Fax: (302) 739-2048

[email protected]@dnrec.state.de.us

Purpose of theStatewide DredgingPolicy Framework

For More Information

About this Document

The Delaware StatewideDredging Policy

Framework

February 2001

Authored by:The Delaware Dredging Working Group

Edited and Prepared by:Jennifer ReidDelaware Coastal ProgramsDivision of Soil and Water ConservationDelaware Department of Natural Resources &Environmental ControlDover, DE

Executive Summary iiiThe Process vMeetings/Workshops of the Dredging Working Group ix

IntroductionOverview of Dredging in Delaware 1Right to Navigable Waters 1

Chapter I. AdministrationAgencies involved in the Permitting Process 3Required Permits of Certifications 3Other applicable Programs, Laws, Considerations 5Joint Pre-Application Meeting 7Administrative and Environmental Information Required for Each Application 7Guidelines for Modifications, Extensions, Suspensions, and Revocations 9Consequences of Violations 9Economics of Dredging 10Maintenance Dredging 12Alternatives to Dredging 12

Chapter II. Environmental EvaluationPre-dredge Evaluation 15

Tier I – Project Scoping 18Tier II – Physical and Chemical Testing 23Tier III – Biological Testing 29Tier IV – Case-Specific Testing 34

During-dredging Analysis 36Post-dredging Monitoring 36

Chapter III. OperationsGeneral Policies 37Dredging Methods and Equipment 40Disposal Methods 41

Open Water Disposal 42Economic Loading or “Barge Overflow” 42Confined Disposal 44Design, Operations and Management (new and existing) of Confined Disposal Facilities 45Alternative Methods and Beneficial Use 48

Best Management Practices 51

TABLE OF CONTENTS

i

References 55

Acronyms 59Glossary 61

AppendicesProject Participants AContact Information BList of Threatened and Endangered Species in Delaware CPermit Application Form for Subaqueous lands, Wetlands, Marina, and 401 Water Quality Certification Projects DPort of Wilmington E

i.1. Dredging Policy Framework Process v2.1. Evaluations at Each Tier 172.2. Tier I Flow Diagram 192.3. Tier II Flow Diagram 242.4. Tier III Flow Diagram 303.1. Dredge Material Management Decision Support Tree 43

2.1. Generic List of Chemicals of Concern 212.2. Effects-Based Biological Tests (for Tier III Evaluation) 323.1. Summary of Dredge Operating Characteristics 403.2. Material Uses by Grain Size 49

Table of Contents

ii

LIST OF FIGURES

LIST OF TABLES

This document is designed to provide an overviewof factors affecting dredging projects in Delaware.Topics related to Administration (policy),Environmental Evaluation (science), andOperations (engineering) are grouped together inchapters. The information contained herein isprovided as an introduction and overview of theprocess. Applicants for dredging permits shouldconsult with the appropriate Agency or Divisionto ensure that they are compliant with the most updated regulations and guidance.

This document is the culmination of workperformed by many individuals and agencies withvaried backgrounds, expertise, and interests.Together, they formed the Delaware DredgingWorking Group, support staff, and stakeholders(see Appendices for full list of participants). Theintroductory section of the document outlines thesteps taken to create the Policy Frameworkdocument, the issues identified, strategiesdeveloped, and final outcome.

The Administration chapter identifies the agenciesinvolved in reviewing and permitting dredgingprojects. It also contains a list of applicable laws,programs, or considerations that might affect thepermitting process. The purpose of this chapteris to familiarize the reader with the complex permitprocess required for dredging projects and toencourage consultation with appropriate agencyofficials at the Joint Pre-Application Meeting.This chapter also includes background informationregarding information requirements, maintenancedredging, consequences of permit violations,economic considerations, and potentialalternatives to dredging.

The Environmental Evaluation chapter organizesthe review of potential environmental impactsfrom a project into a four-tiered system. The tiersare based upon project size and complexity as wellas the location of the work. The level of reviewthat a project requires will be determined by

Delaware Department of Natural Resource andEnvironmental Control (DNREC) staff. Whateverreview is undertaken during the pre-dredgeevaluation must then be confirmed through during-dredging and post-dredging surveys.

The Operations chapter is intended to providebackground on different dredging methods and toencourage applicants to select the method with theleast environmental impacts for their particularsituation. It also lists general policies regardingdredging location and project design, outlines bestmanagement practices, and provides criteria forappropriate dredging and disposal operations.

The Appendices include lists of processparticipants, additional standards and regulations,information regarding the Port of Wilmington andother material referred to in sections of thedocument.

EXECUTIVE SUMMARY

iii

THE PROCESS

Because issues related to dredging involvediffering interests and various levels of projectreview and regulatory oversight, Delaware CoastalPrograms (DCP) has developed this DredgingPolicy Framework through a collaborativedecision-making process. A Working Groupstructure was used, with members providingbackground expertise on the various componentsof the dredging process and advising DCP on thecontent of the Policy Framework document. Thiscollaborative decision-making reliedfundamentally on the participation, input, andagreement of resource managers, scientists, andcommercial and residential interests.

The original goal of this project was as follows:

“The goal of the Dredging Working Group is todevelop and implement a Statewide DredgingPolicy Framework. This Framework will:

- Provide clear guidance and earlycoordination between regulatory agenciesand applicants;

- Provide a basis to evaluate projectjustification based upon economic andenvironmental impacts;

- Identify data requirements and provideresources to maximize the use of existinginformation;

- Identify preferred dredging methods anddisposal options, including beneficialuses;

- Provide a consistent approach to testingand monitoring activities; and

- Provide education and public outreachregarding dredging activities in Statewaters.”

The above goal was clearly defined at the outsetby the Working Group and was used to maintainfocus throughout the process.

The project was divided into six phases (see Figurei.1), each with a well-defined goal and identifiedproduct. The first phase of this project convenedthe Dredging Working Group, a group of about25 members representing the stakeholder groupsinvolved with dredging in Delaware waters. Therole of the Working Group was to identify issuesrelated to dredging in the State, to explorealternatives and solutions, to advise the DCPregarding the content and themes in the DredgingPolicy Framework Document, and to assist in thedrafting of that document.

The next phase of this process was a one-daydesign symposium, which gathered a larger groupof experts who have experience with problems andissues similar to those identified by the WorkingGroup. These experts were divided into threefocus groups according to their area of expertise– Administration (policy), Operations(engineering), and Environmental Evaluation(science), where they discussed and evaluatedalternative approaches to the problems presented.Some groups also developed methodologies forparticular components of the issues (i.e. testingprotocols, management practices, disposal options,beneficial re-use alternatives, coordinationimprovements, etc.). The final result of thisworkshop was a Workshop Proceedings documentcontaining recommendations from each focusgroup.

After this workshop, the Working Groupreconvened and reviewed the WorkshopProceedings. Small focus groups were formed inorder to provide further guidance on particularsections of the Framework. The goal of this phasewas to arrive at a means for implementing thepriority Dredging Policy Framework components.DCP staff used these recommendations, along withfurther consultation with the Working Group, todraft this Policy document. The Working Grouphas had the opportunity to review all interim and

v

final products related to the Policy Framework.

There are a number of issues that arose during thisprocess that were not able to be fully addressedduring the drafting of this document. However,the Working Group felt that many of these issueswere valuable and worthy of future consideration.These issues include the following:

- long term dredging priorities- Best Management Practices for Confined

Disposal Facility (CDF) closure- policies for non-tidal ponds- more specific monitoring guidelines for

during and after dredging- analysis of technical and administrative

capacity to implement the frameworkoutlined in this document and expand itsscope

- “National Environmental Policy Act(NEPA)-like” process of alternativesanalysis

- education and public outreach efforts- the role of private and public-owned

dredges- economic policy with respect to dredging- sediment loading to watersheds (pollution

prevention)- Geographic Information System (GIS)

database and analysis system for dredgingprojects

- review of Inland Bays guidelines- long term disposal plan- beach disposal sediment criteria- abridged version of this document for

permit applicants.

The Working Group recommends that the aboveissues be addressed by future efforts related to thepermitting of dredging activities and that thecurrent document be examined with theunderstanding that these items are missing.

The Process

vi

Figure i.1. Dredging Policy Framework Process Diagram

Define Dredging Issues in an operational and systematic

manner that includes Delaware scientists, analysts,

and managers as well as some national experts in the

field.

Defining the Issues

Develop a detailed description of the issues and information needs.

Define what is and is not known about a given

issue.

Preliminary Issue Characterization

Phase 1 Phase 2

Month 1-2 Month 2-4

Gather State & National experts in dredging issues

Identified, GIS, and information management who

have specific experience to outline the alternative

approaches that could be used to address dredging issues

previously identified.

Strategy Development

Phase 3

Month 4-6

Prioritize the fully characterized issues.

Draft Strategies to address the priority

issues.

Strategy Refinement

Phase 4

Month 6-8

Build Strategies into a policy framework that can

be used to guide future dredging activities.

Policy Development

Phase 5

Month 8-14

Refine Policy based on assessment of success

from tracking the supporting Information Management System

Track and Refine Policy

Phase 6

Month 15-22

Approved DCMP Policy Framework for

Decision Making Related to Dredging

Information Management System to Support DCMP Dredging Policy

Framework and Assessment (GIS Based)

Month 24

Month 24

Final Products

Stream ofProducts First Draft

Issue Characterizations

Workshop Summary

Suggested Strategies

First Draft Strategies

Policy or Science tools to address the Issues.

Performance measures.

Detailed Strategies

Operational policy tools for handling dredging issues.Specific performance measures for tracking.

MEETINGS/WORKSHOPS OF THE DREDGING WORKING GROUP

Date/Location

4/27/99Grass Dale Conference CenterDelaware City, DE

6/3/99Grass Dale Conference CenterDelaware City, DE

7/13/99St. Jones ReserveDover, DE




12/7/99Clayton Hall,University of DENewark, DE



6/8/00

9/19/00St. Jones Reserve

Purpose/Result

Presented overview of project, reviewed initial issue statements and groupings, andadded additional members to represent stakeholder groups.

Reviewed current process for dredging applications, reviewed issues and groupingcategories, and began issue characterization.

Reviewed draft Issue Characterization document, refined list of issues, identifiedadditional information needed, and identified individuals to work on issue refine-ment.

Reviewed and finalized Issues Characterization document, developed preliminarylist of tools or actions to address issues, and began planning Strategy Workshop.

Presented, reviewed, and selected process to complete Policy Framework, and beganfirst steps of strategy development phase.

Reviewed plans for Strategy Workshop and reviewed issues in preparation forstrategy development.

Reviewed issues developed, brainstormed ideas/solutions to address each issue, anddeveloped detailed descriptions of each strategy.

Reviewed workshop results, updated project status, detailed next steps, initiatedefforts to finalize document components, and identified key members to completeoutstanding tasks.

Environmental Evaluation Focus Group met to discuss section.

First draft of Policy Framework mailed to Working Group for comment.

Reviewed final comments on document draft.

ix

INTRODUCTION

Overview of Dredging in Delaware

Appropriate dredging in waters of the State ofDelaware is necessary for movement of maritimetraffic into ports, movement of recreational trafficin rivers and bays, beach replenishment, coastalhazard mitigation, maintaining water intakes, orremoval of contaminated sediment. Ifaccomplished pursuant to established reviewcriteria, this dredging can be an importantcomponent to a healthy coastal economy andenvironment. In certain cases, if dredgingactivities were to cease, there could berepercussions for local employment or for theeconomy both regionally and/or nationally, as inthe case of the Delaware River Main Channel.

The state’s tourism industry is supported in partby the recreational opportunities provided by statebeaches and public boat access areas. Dredgingassociated with beach replenishment andnavigation ensures the strength of this importantindustry.

The diversity of dredging activities in state waterscreates a wide range of issues and concerns, andthis document will attempt to address and clarifyas many as possible.

Right to Navigable Waters

The initial consideration that must be examinedin any water-based project is whether the applicantindeed has the authority to conduct the activity.In general, a riparian landowner does have someright of access to navigable waters of the UnitedStates. However, this right is subject to the similarrights of access held by nearby riparian landownersand to the general public’s right of navigation onthe water surface. In the absence of overridingpublic interest, favorable consideration willgenerally be given to applications from riparianowners for permits for piers, boat docks, moorings,

platforms, and similar structures for small boats.

Delaware is one of only a few states to recognizea coastal landowner’s grant seaward to the lowwater mark. “[A] riparian owner…holds to lowwater mark and thus its title includes the foreshore”(State ex rel. Buckson v. Pennsylvania RailroadCo., 228 A.2d 587, 600 (1967)). However, despitethe private ownership of tidelands extending tothe “ordinary low water mark,” the public stillretains the public trust right to utilize the beachup to the “ordinary high water mark.”

“In general, common law riparian rights include aright of access to reach the water, the right toaccretions, the right to an unobstructed view, aqualified right to wharf out, the right to makecommercial use of water access, the right to makereasonable use of the water, and the right ofnavigation in common with the public” (Christie,1994). Riparian rights have long been consideredvested property interests. However, “what werepreviously regarded as riparian ‘rights’ can bedescribed today as merely riparian ‘privileges’”(Slade, 1997), and these must be balanced againstpublic rights and concerns.

Access to the water by waterfront landowners isnot unlimited. The right to use the water is incontext with the location and must be balancedwith the right of the general public to use thewaterbody. Rights do not include an unlimitedability to dredge to any depth necessary or desired,nor to wharf out unrestricted. “Dredging to obtainnavigable water depths in conjunction with privateresidential boat docking facilities should beavoided” (Regulations Governing the Use ofSubaqueous Lands, 3.03 (B) 13).

“The Department shall consider the public interestin any proposed activity which might affect the

1

use of subaqueous lands.” These considerationsinclude, but are not limited to, the following:

1. The value to the State or the public in retainingany interest in subaqueous lands which theapplicant seeks to acquire, including thepotential economic value of the interest.

2. The value to the State or the public inconveying any interest in subaqueous landswhich the applicant seeks to acquire.

3. The potential effect on the public with respectto commerce, navigation, recreation, aestheticenjoyment, natural resources, and other usesof the subaqueous lands.

4. The extent to which any disruption of thepublic use of such lands is temporary orpermanent.

5. The extent to which the applicant’s primaryobjectives and purposes can be realizedwithout the use of such lands (avoidance).

6. The extent to which the applicant’s primarypurpose and objectives can be realized byalternatives, i.e. minimize the scope or extentof an activity or project and its adverseimpacts.

7. Given the inability for avoidance oralternatives, the extent to which the applicantcan employ mitigation measures to offset anylosses incurred by the public.

8. The extent to which the public at large wouldbenefit from the activity or project and theextent to which it would suffer detriment.

9. The extent to which the primary purpose of aproject is water-dependent (RegulationsGoverning the Use of Subaqueous Lands, 3.01(A)).

Introduction

2

CHAPTER 1. ADMINISTRATION

Purpose

This chapter covers a wide range of topics, allrelated to permitting, project review, and other“pre-project” considerations. Its aim is to presentan introduction to important administrative topicsthat should be addressed when designing adredging project. This chapter begins with anoverview of the agencies involved in the projectreview process and some of the key regulatoryprograms and laws or regulations. The bulk ofthe chapter enumerates information required foreach permit, the consequences of supplying falseinformation or not complying with permitconditions, and the guidelines for extensions ormodifications. A section on maintenance dredgingdefines how a “repeat” project may be defined ortreated differently than a completely new project.The economics section introduces the policies usedto address cost-benefit issues from the Federal,State, and private perspective. The alternativessection emphasizes that the State encouragesapplicants to find alternative means to accomplishproject goals or to minimize the scope of theirproject.

AGENCIES INVOLVED IN THE PERMITTING PROCESS

Federal:U.S. Army Corps of Engineers, Philadelphia or

Baltimore DistrictNOAA National Marine Fisheries ServiceU.S. Environmental Protection AgencyU.S. Fish and Wildlife Service

State:DNREC, Division of Water Resources,

Wetlands and Subaqueous Lands SectionDNREC, Division of Soil and Water

Conservation, Delaware Coastal Programs

DNREC, Division of Soil and WaterConservation, Sediment and StormwaterSection

DNREC, Division of Fish and WildlifeState Historic Preservation Office

In Delaware, dredging activities are regulated bythe U.S. Army Corps of Engineers, (Philadelphiaor Baltimore District) and the DNREC, Divisionof Water Resources, Wetlands and SubaqueousLands Section, but other agencies may also beinvolved in the process. The location, activitiesproposed, and applicant all affect which agenciesand permits will have jurisdiction. Applicants areencouraged to attend the Joint Pre-ApplicationMeeting described in this section and/or to contactagency representatives to discuss particularproject considerations.

The regulatory programs of both Federal and Stateagencies require that an applicant obtain permitapproval before undertaking a project. In addition,the Delaware Coastal Programs section, under theDNREC, Division of Soil and WaterConservation, requires an applicant to providecertification that a proposed project complies withthe State’s coastal zone management program.

An integral part of the permit acquisition processis the public notice and public interest reviewwhich affords other federal and State regulatoryagencies (e.g. U.S. Environmental ProtectionAgency, State Historic and Cultural Affairs Office)and the general public an opportunity to reviewand comment on any given proposal. The Corpsand DNREC evaluate each project by balancing

REQUIRED PERMITS OF CERTIFICATION

3

the need and expected benefits against the probableimpacts, taking into consideration all commentsreceived and other relevant factors. Below is abrief explanation of the major permit approvalsneeded for most dredging projects in the state. Thecontact agency listed can provide additionalinformation.

U.S. Army Corps of Engineers Permits

The regulatory authorities and responsibilities ofthe Corps of Engineers are based on the followinglaws: Section 10 of the Rivers and Harbors Act of1899 (33 U.S.C. 403) “prohibits the obstructionor alteration of navigable waters of the UnitedStates without a permit from the Corps”; Section404 of the Clean Water Act (33 U.S.C. 1344)“prohibits the discharge of dredged or fill materialinto waters of the United States without a permitfrom the Corps”: and Section 103 of the MarineProtection, Research, and Sanctuaries Act of 1972,as amended (33 U.S.C. 1413) “authorizes theCorps to issue permits for the transportation ofdredged material for the purpose of dumping itinto ocean waters.” Applicants are required toobtain a Department of the Army (DA) individualpermit (see 33 CFR 323). This process involves apublic notice period as well as consultation withthose Federal and State agencies which governenvironmental quality, fish and wildlife,endangered species and historic preservation.

Contact: U.S. Army Corps of Engineers,Philadelphia District, Regulatory Branch.

Federal Consistency

Section 307(c) of the Coastal Zone ManagementAct of 1972, as amended (16 U.S.C. 1456(c)),requires “federal agencies conducting activities .. . directly affecting a state’s coastal zone, tocomply to the maximum extent practicable withan approved state coastal zone managementprogram. . . .” The Act also requires any non-federal applicant for a federal license or permit toconduct an activity affecting land or water uses inthe state’s coastal zone to furnish a determination

that the proposed activity will comply with thestate’s coastal zone management program (33 CFR320.3(b)).

This means that most persons applying for adepartment of the Army permit will also berequired to obtain a federal consistencydetermination from the sate Coastal ZoneManagement Program. Applicants for CZMFederal Consistency are subject to an additionalpublic notice period of either 15 or 30 days. Afederal permit cannot be issued if CZM FederalConsistency is denied.

Contact: DNREC, Division of Soil andWater Conservation, Delaware CoastalManagement Program

Water Quality Certification

Section 401 of the Clean Water Act (33 U.S.C.1341) requires “any applicant for a federal licenseor permit to conduct any activity that may resultin a discharge of a pollutant into waters of theUnited States to obtain a [Water QualityCertificate]from the State in which the dischargeoriginates or would originate . . .” (33 CFR320.3(a)). The applicant must provide areasonable assurance that water quality standardswill not be violated. A federal permit cannot beissued if Certification is denied. Requirementsfor Water Quality Certificates are project specific.

Contact: DNREC, Division of WaterResources, Wetlands and SubaqueousLands Section.

Subaqueous Lands Permits

7 Delaware Code 7205 states that “No person shalldeposit material upon or remove or extractmaterials from, or construct, modify, repair orreconstruct, or occupy any structure or facilityupon submerged lands or tidelands without firsthaving obtained a permit, lease or letter of approvalfrom the Department.” This means that alldredging projects within State boundaries must

Chapter 1. Administration

4

obtain subaqueous permits.

“A person seeking a lease or permit shall submitto the Secretary [of DNREC] a written request,using the appropriate forms available from theDepartment, stating in detail the type of grant,lease or permit desired, showing the location ofthe area and containing specifications for anyproposed activity” (Regulations Governing theUse of Subaqueous Lands 2.01 (A)).


State Wetlands Permits

7 Del C. 6604 requires that any activity in tidalwetlands must obtain a permit from the DNREC.Wetlands subject to the provisions of the WetlandsAct are delineated on regulatory maps that werelast revised in 1992.


Clean Water Act

Section 404 of the Federal Clean Water Actauthorized the Corps of Engineers (or a Stateagency with an authorized permit program) toissue permits for the discharge of dredged or fillmaterial into waters of the United States.

Delaware Natural Heritage Program

The Delaware Natural Heritage Program (DNHP)conducts systematic biological surveys throughoutthe State of Delaware for the purpose of locatingpopulations of rare or unique plant and animalspecies, and to identify and describe significantnatural communities. The data is then used for avariety of purposes including environmental

review services for project applicants. The DNHPstaff has the capability to do data searches as wellas on-site inventories, and information on thesecan be acquired by contacting the Program, whichis located within the DNREC Division of Fish andWildlife.

Delaware Sediment and Stormwater Law and Regulations

“After July 1, 1991, unless a particular activity isexempted . . . , a person may not disturb land with-out an approved sediment and stormwater man-agement plan from the appropriate plan approvalagency. A grading or building permit may not beissued for a property unless a sediment andstormwater management plan has been approvedthat is consistent with the following items:

A. Chapter 40, Title 7, Delaware Code, relatingto erosion and sediment control andstormwater management, and;

B. These regulations, or duly adopted county ormunicipal ordinances that are adopted as a partof the delegation process and relate to the in-tent of these regulations (Delaware Sedimentand Stormwater Regulations, Section 8(1)).”

Contact: DNREC, Division of Soil & WaterConservation

Delaware State Historic Preservation Office Review

Section 106 of National Historic Preservation Act(NHPA) requires federal agencies and recipientsof federal assistance or permits to take into accountthe effects which the project may have onsignificant historic properties and sites. Applicantsmust preserve, either physically or throughextensive documentation, any significant historicproperties that may be harmed by these projects.Applicants should consult the Delaware StateHistoric Preservation Office (SHPO) in order todetermine if applicable sites lie in the vicinity ofthe proposed project area.


5

OTHER APPLICABLE PROGRAMS, LAWS, AND CONSIDERATIONS AFFECTING PERMIT PROCESSING

Endangered Species Act

The Federal Endangered Species Act provides forthe designation and protection of invertebrates,wildlife, fish, and plant species that are in dangerof becoming extinct and conserves the ecosystemson which such species depend. The U.S. Fishand Wildlife Service (FWS) and National MarineFisheries Service (NMFS) have jurisdiction underthis Act and should be contacted regardingpresence of listed Threatened or EndangeredSpecies.

EPA/USACE Inland Testing Manual

The document entitled Evaluation of DredgedMaterial Proposed for Discharge in Waters of theU.S. – Testing Manual (EPA/USACE, 1998) iscommonly known as “The Inland TestingManual.” It provides guidance for conductingtesting of dredged material to assess the potentialfor contaminant-related impacts associated withdredged material disposal into open water. It isdesigned to aid permitting authorities in makingdeterminations regarding whether the dischargewill comply with the 404(b)(1) Guidelines fordischarge as laid out in the Clean Water Actregulations (see above).

Marine Protection Research and Sanctuaries Act of 1972

The basic objective of the Marine ProtectionResearch and Sanctuaries Act is to “prevent orstrictly limit the dumping into ocean waters of anymaterial that would adversely affect human health,welfare, or amenities, or the marine environment,ecological systems, or economic potentialities.”This Act authorizes the Secretary of the Army toissue permits for dredged material disposal, andthe EPA to designate appropriate dump sites.

National Environmental Policy Act

The National Environmental Policy Act (NEPA)mandate compels informed decision-making byfederal agencies and their departments by requiring

consideration of all relevant environmentalconsequences of proposed actions and involvingthe public in the decision-making process. Allagencies of the federal government must considerthe environmental impacts, the short-term andlong-term effects, any unavoidable harms to theenvironment, and feasible alternatives to anyproposed action. This review is commonlyundertaken through an Environmental ImpactStatement (EIS) process.

Essential Fish Habitat, National Marine Fisheries Service Consultation

The 1996 amendments to the Magnuson-StevenAct, which regulates fishing in U.S. waters,included new provisions for protecting the habitatsof all federally managed species of marine oranadromous fish. The Act defines Essential FishHabitat (EFH) as “those waters and substratenecessary to fish for spawning, breeding, feeding,or growth to maturity.” Any action authorized,funded, or undertaken by a federal agency that mayadversely affect EFH requires the federal agencyto consult with the National Marine FisheriesService (NMFS) regarding the effects of the actionon EFH.

U.S. Fish & Wildlife Coordination Act

The Fish & Wildlife Coordination Act (FWCA)ensures that fish and wildlife resources receiveequal consideration with other values during theplanning of water resources development projects.It requires the Department of Energy to consultwith the Fish & Wildlife Service whenever it plansto conduct, license, or permit an activity involvingthe impoundment, diversion, deepening, control,or modification of a stream or body of water. TheAct also requires consultation with the head of thestate agency that administers wildlife resourcesin the affected state. The purpose of this processis to promote conservation of wildlife resourcesby preventing loss of and damage to such resourcesand to provide for the development andimprovement of wildlife resources in connection


6

with the agency action.

Water Resources Development Act

The Water Resources Development Act (WRDA)authorizes the U.S. Army Corps of Engineers toprovide assistance to state, county, or local entitiesfor undertaking certain dredging, restoration,beach nourishment, or beneficial use projects.

The Joint Pre-Application Meeting (JPM) meetingprovides a forum for permit applicants to presentand discuss a proposed project with the majoragencies involved in the permitting process priorto submitting formal applications. The intent isfor the agencies to explain to applicants how thepermitting process works and to providecomments and suggestions to them that mightenhance their respective projects (e.g. methods tominimize impacts). In addition, permit applicantsare encouraged to use qualified contractors whoare familiar with the permitting requirements andprocess. While a pre-application consultation atthe Joint Pre-Application Meeting is notmandatory, it is strongly recommended as a wayfor applicants to gain a better understanding ofthe jurisdictions that could impact their particularproject. Currently a monthly JPM meeting is heldat the DNREC Building in Dover. Agencies thatregularly attend include the U.S. Army Corps ofEngineers, the U.S. Environmental ProtectionAgency, the U.S. Fish & Wildlife Service, theNOAA National Marine Fisheries Service, theDNREC Divisions of Fish & Wildlife, WaterResources, and Soil and Water Conservation, andthe State Historic Preservation Office.

To present a project at JPM, applicants need tocontact the DNREC, Division of Water Resourcesto obtain an appointment on the JPM schedule.Projects that can benefit from the JPM include new

dredging projects, new projects with a dredgingcomponent, and maintenance dredging projects,where the U.S. Army Corps of Engineers and/orDNREC determine that changes in regulatorypolicies or resource information could affectproject design. The process is designed to bemutually beneficial to both the applicant and thepermitting agencies. Applicants are made awareof the necessary permits required for individualprojects, and modifications which can minimizeenvironmental damage or even provideenhancement can be considered while the projectis still in the planning stages.

The following information must be provided withany permit application. The information isintended to assist project review agencies to fullyevaluate impacts from a proposed project.Additionally, the checklists for dredging impactsand/or confined disposal facilities should be usedas they apply to the project. The majority of thisinformation is already requested in the U.S. ArmyCorps of Engineers’ standard ENG Form 4345permit application along with the correspondingenvironmental questionnaire, and the State’s JointPermit Application for Subaqueous Lands alongwith the appropriate appendices. Any additionalrequests here should supplement that informationin order to provide federal and State regulatorypersonnel with the maximum information possibleto review and assess the impacts associated witheach project. Applicants should refer to theEnvironmental Evaluation Chapter of thisdocument for more information on the tieredapproach used to evaluate project data.

ü Project description: 1) purpose, 2) need, 3)benefits.

ü Is the work being done by a public agency or


7

JOINT PRE-APPLICATION MEETING

ADMINISTRATIVE AND ENVIRONMENTAL INFORMATION

REQUIRED FOR EACH APPLICATION

a private individual/company?ü Proposed project dimensions, including

length, width, depth.ü Plan drawings (8.5” by 11” with photographs).ü Dredging volumes (amount to be dredged).ü Existing depths in project area (hydrographic

survey at 100-foot intervals).ü Method of dredging (hydraulic or mechanical).ü Dredging site location (name of waterway and

coordinates).ü Disposal method proposed and site location.ü Sediment type/characterization (sediment

composition and grain size).ü Anticipated number and location of ancillary/

secondary channels.ü Classification of waterway (for projects in

Delaware’s Inland Bays region refer toclassification criteria established in the “InlandBays Dredging Study”).

ü Alternatives analysis – discuss the effect ofnot doing the project (i.e. the “no action”alternative) as well as alternative methods ofdredging or disposal to minimize impacts.

ü Need for maintenance dredging.- For maintenance projects, volume of

material dredged within last 10 yearsduring each dredging episode.

- For new projects, estimate expectedfrequency/volume for maintenance.

Checklist for Dredging Activities

The following information is needed to addressthe potential environmental impacts at thedredging site. These should be addressed by theproject applicant if at all possible. For moreimpact-related information needs, refer to the TierI section in the Environmental Evaluation chapter.

ü Location information adequate to ensureproper siting of the project (e.g. USGSquadrangle maps)

ü Characterize existing biological community(sampling requirements).

ü Characterize existing water quality anddesignated use areas.

ü Applicable time-of-year restrictions and

schedule of project implementation.ü Does the area qualify as Essential Fish

Habitat?ü Are there threatened or endangered species in

the area?ü Inventory of potential historical/cultural

resources.ü Potential impacts to existing currents.ü Potential impacts to shoaling patterns.ü Potential biological impacts to aquatic and

semi-aquatic species.ü Methods to minimize impacts during dredging.ü Chemical constituents of sediments.ü Will project result in additional user conflicts?ü Anticipated length of project.ü Has the applicant attended (or scheduled) a

pre-application consultation at Joint Pre-Application Meeting?

ü Is the applicant committed to maintaining thechannel in future?

Checklist for Dredged Material Confined Disposal Facilities

When an upland confined disposal facility isproposed as the management option for thedredged material, the following questions andissues will be necessary for regulatory agencypersonnel to fully evaluate the project proposal.

ü Site location: including 1) latitude, 2)longitude, 3) tax parcel.

ü Plan drawings of facility (8.5” by 11”).ü Owner(s) of disposal facility.ü Method of containment.ü Environmental setting.ü What contaminants might be (or have been)

found in the material to be dredged?ü What is the potential for these contaminants

to end up in the discharge from the CDF asthe dredged material dewaters (impacts tosurface water)?

ü What is the effluent quality expected in termsof solids, biological oxygen demand, andcontaminants?

ü Are there contaminants which may leach and


8

cause impacts to groundwater?ü Are there potential impacts on mosquito

breeding?ü List any secondary impacts from transporting

the dredged material to disposal facility.ü Impacts to adjacent lands/properties (safety,

land use compatibility).ü Other approval(s) required.ü Method of dredging (hydraulic or mechanical).ü Monitoring requirements (effluent/receiving

waters).ü Can the applicant conclusively demonstrate

that they will be able to achieve compliancewith water quality standards?

ü Impacts to historical/cultural resources.ü Potential impacts to ecosystem.

The information above should address thephysical, chemical, and biological effects from aproposed project. While the USACE/USEPAInland Testing Manual addresses primarilychemical (contaminant) impacts, the State ofDelaware intends to extend project reviews toincreasingly include impacts to biologicalcommunities. This document is the first step inthis goal, and future editions will aim to developthis area of review in more specific detail.

Modifications

Examples of modifications to permits that areregularly received by permitting agencies includechanges to seasonal restrictions when necessaryto complete the work and adding seasonalrestrictions based on new biological information.Any modification requires amending the permit.If the modification is major, it is placed on publicnotice again. If it is minor, the permit can beamended without public notice requirements.

Extensions

If a permit has not expired it can generally beextended by submitting a letter of request. If it

has expired, a new application must be submitted.Wetlands permits can receive two extensions ofone year each. After that, the existing permitcannot be extended further without a newapplication submitted and new permit issued.

Suspensions and Revocation

Revocation of an approved permit could occur ifnew or false information makes a re-evaluation ofthe permit decision necessary. A permit can besuspended/revoked if any of the conditions in theoriginal permit are violated.

Serious consequences exist for persons violatingfederal and/or state laws, permits, or otherenvironmental requirements. The Delaware Codestates the following with regard to violations:

“No personal shall, without first having obtaineda permit from the Secretary, undertake any activity. . . in a way which may cause or contribute todischarge of a pollutant into any surface or groundwater” (7 Delaware Code 6003). “Dredged spoil”is included in the list of potential pollutants andthus is regulated under Chapter 60.

Consequences of submitting false information “inany application, record, report, plan or otherdocument filed or required to be maintained . . .[shall] be punished by a fine of not less than $500nor more than $10,000 or by imprisonment fornot more than 6 months, or both.” (7 DelawareCode 6013).

With respect to wetland violations, theconsequences are similar. “Any person whointentionally or knowingly violates any rule,regulation, order, permit condition or provisionof this chapter shall be fined not less than $500 ormore than $10,000 for each offense” (7 DelawareCode 6617(a)). “In addition to any penaltiesimposed under this section . . ., a person who


9

GUIDELINES FOR MODIFICATIONS, EXTENSIONS, SUSPENSIONS

AND REVOCATIONS

CONSEQUENCES OF VIOLATIONS

effects or permits any activity in wetlands inviolation of this chapter may be liable to the Statefor the cost of restoration of the affected wetlandto its condition prior to such violation insofar asthat is technically feasible” (7 Delaware Code6620).

Dredging projects in Delaware waters areconsidered for implementation based upon theassumption that the project will provide publicand/or private benefits. These benefits mayinclude economic benefits to commerce ortourism, and/or recreational benefits to publicusers of the state’s waterways. The assessmenttechniques for benefits vary depending uponwhether the project is Federally funded, state-funded, or privately funded. The process for cost-benefit evaluations for each is briefly outlinedbelow.

General Economic Analysis

Several questions need to be asked when dredgingprojects are presented. These questions includewhether the project applicant/sponsor providedproper and adequate economic justification (whereapplicable), who evaluated the cost-benefitanalysis and what type of methodologies wereused, how the economic benefits will be dividedbetween local, state, and national entities, andwhether the funding source is adequate to coverall project phases, including money for necessaryenvironmental assessments and impact statements.

Evaluating the economic feasibility of a projectbegins with determining its direct economicbenefits (i.e. the value of a widened and/ordeepened channel). The economic value wouldbe the (hypothetical) willingness of the additionalboaters accommodated by the project to pay forits costs. Other outputs to be considered include

increases in the capacity or productivity of naturalor recreational resources, increases in propertyvalues, reduced occurrences of natural disasters,and improvement in environmental quality. Insome cases, these benefits are not normallymeasured in economic terms, so their value mustsomehow be translated into dollar units (or“monetized”) in order to be weighed against theeconomic and monetized environmental “costs.”

Benefit must then be analyzed to determine whatportion constitutes a “public benefit” – benefitswhich are equally accessible to all members ofthe public. Since public funds support the cost ofDelaware’s dredging program, the public must bethe primary beneficiary. A significant proportionof the economic benefits of a dredging project musteither be equally accessible to all members of thepublic, or must be in the form of a collectivebenefit. In some projects, private benefits such asincreased property values may be unavoidablyproduced. However, it is important that the benefitto the general public outweighs that to privateindividuals and that the purpose of the projectbegins as a public endeavor.

Likewise, total costs must be calculated, includingeconomic costs, costs of lost opportunities, andenvironmental damages. As in the case of non-monetary benefits, it is also difficult to calculatecosts for environmental damages. While a strictcost-benefit analysis is not required for non-Federal projects, this methodology provides aguide for complete analysis of the direct andindirect impacts (in economic terms) of dredgingprojects. Additionally, the environmental costsmust be at least qualitatively weighed inexamination of the cost-benefit of the project.

The following section from the WetlandsRegulations shall be applied generally to all typesof dredging activities:

“Economic Impact shall include a short and long-term evaluation of the following factors to theextent the effect is directly attributable to theproposed activity:

10


ECONOMICS OF DREDGING

A. Jobs created or lost and the net income effectsof jobs.

B. Increases in revenues to or increases inexpenditures by State, County and localgovernments (e.g. increased taxes from anincreased tax base and increased expenditurefor maintaining supporting facilities).

C. Increases or decreases in the value attributableto the wetland [or waterbody] as a source ofnutrients to finfish, crustacea and shellfish andas habitats of such species or other flora orfauna of significant actual or potentialeconomic value.

D. Increases or decreases in the value of the land[or water] as a recreational area.

E. Increases or decreases in the cost of floodcontrol or expected flood damage which mightbe caused by the effect of the activity on thenatural capacity of the wetland to reduce flooddamage.

F. Increases or decreases in the costs ofmaintaining navigable harbors and waterwayswhich would result from altering the capacityof the wetlands to absorb silt.

G. The net economic effect, both public andprivate, of any contemplated supportingfacilities.

H. The net economic effect, both public andprivate, of the proposed activity onneighboring land uses” (Wetland Regulations,Section 7.07).

Federal Dredging Projects

Federal projects require a positive cost-benefitratio as defined by U.S. Army Corps of Engineers(USACE) regulations. The ratio is based uponthe National Economic Development (NED) plan.The NED considers benefits from the nationalperspective rather than from a regional, state, orlocal perspective. This can at times lead toconfusion at the local level, especially whensignificant benefits occur in adjacent states orregions or nationally, but not locally. The USACEhas economic guidelines and standards for thisprocess.

State Dredging Projects

For State of Delaware dredging and beachnourishment projects, funding is appropriated bythe state’s General Assembly. Therefore, it isassumed through the appropriations by an electedrepresentative body that public benefits exceedcosts. However, no specific cost-benefit analysisis required for state-funded dredging projects, nordoes appropriation imply an environmentallysound project. Historically, appropriations haveincluded funding of the Division of Soil & WaterConservation’s state dredge program throughgeneral legislative mandate and additional specialproject appropriations.

Under Delaware statute, the state dredgingprogram has the authority to act as a contractorfor private dredging projects. However, theDivision of Soil & Water Conservation (DSWC)discontinued this activity in 1997.

7 Delaware Code 3905(b)(13) authorized the stateto “[c]ooperate with other agencies and depart-ments of the State, federal agencies, or any otherlandowners for use of the state dredge at the costof the state agency and/or department, federalagency or the landowners requesting use of thestate dredge.” As a result of this, DSWC periodi-cally acted as a contractor for private dredgingprojects. However, in 1997 this activity was dis-continued. Therefore the DSWC will no longerenter into contractual agreements with privatelandowners. However, the Division does main-tain an interest in doing work for public or quasi-public entities (e.g. Division Fish & Wildlife, U.S.Coast Guard, University of Delaware,etc.).

A significant portion of work conducted by thestate dredge is for beach nourishment. Sincecoastal property is highly valued, beach erosionassociated with major storms is a significanteconomic problem along the coast and many areasof the Delaware Bay. The state is working closelywith the federal government to develop a long-term strategy to deal with shoreline erosion andto discourage development in high-hazard areas.


11

The Delaware Coastal Management Program hasa Coastal Management Policy (CMP) for BeachManagement which states that “[t]he public andprivate beaches of the State shall be preserved,protected, and enhanced to mitigate beach erosion,and to prevent their destruction and despoilation”(Authority – 7 Delaware Code 6801, 6803, and8610).

Additionally, “[t]he Secretary [of DNREC] mayundertake any or all necessary works to restoreprivate beaches as designated by the Department,whenever two thirds or more of the propertyowners in the project area along the private beachhave petitioned the Department to undertake thework.” (7 Delaware Code 6810).

Private Dredging Projects

It is assumed that a private applicant perceives an(economic) benefit, which leads him/her to submita project application. On the surface, such benefitsmay not be clearly economic, as they would be ifcommerce were involved. Instead, the benefitsmay be in the form of recreational enjoyment orease of access. Property owners invariably doinformal calculations, deciding whether the costof gaining water access is outweighed by thebenefits they will receive. Since the perceivedbenefits will be enjoyed by a private entity orindividual, the cost of the project is also to beprivately borne.

Since the benefits of “private” dredging are notpublicly enjoyed, the cost of maintaining suchchannels must not be publicly borne. Additionally,the private benefits must not be achieved at a“cost,” including environmental damage, to nearbylandowners or the general public. Applicantsshould also be advised that maintenance,monitoring, and mitigation costs may add to thetotal price of a project.

Maintenance dredging is defined as the restorationof a channel, berthing area (e.g. marina basin), orcooling-water intake area to a depth no greater thanthat allowed by a previous project or permit aslong as the intended purpose or use of the areahas not changed. Maintenance dredging projectsundergo critical review of environmental impacts.

Future maintenance requirements, as well as anycurrent, related work should be considered in anypermit application for new dredging. Review ofmaintenance dredging and repeated projects willconsider analysis of secondary and cumulativeimpacts and assessment of long-term impacts.

Subaqueous lands permits are issued formaintenance dredging for a 3 to 5 year limit,depending on the severity of the predicted impacts.The time length is determined on a case-by-casebasis by the Wetlands and Subaqueous LandsSection.

To define the justification and purpose of proposeddredging projects, practical and feasible methodsto accomplish the project purpose should beanalyzed. Applicants are required as part of theCorps of Engineers Individual Permit applicationto provide at least an analysis of the “no action”alternative.

Likewise, the State of Delaware’s SubaqueousLands Regulations also require an analysis of thealternatives to the project in the section quotedhere. “The Department [of Natural Resources andEnvironmental Control] shall consider the publicinterest in any proposed activity which mightaffect the use of subaqueous lands. Theseconsiderations include, but are not limited to, thefollowing:

MAINTENANCE DREDGING

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ALTERNATIVES TO DREDGING

1. The extent to which the applicant’s primaryobjectives and purposes can be realizedwithout the use of such lands (avoidance).

2. The extent to which the applicant’s primarypurpose and objectives can be realized byalternatives, i.e. minimize the scope or extentof an activity or project and its adverseimpacts.

3. Given the inability for avoidance oralternatives, the extent to which the applicantcan employ mitigation measures to offset anylosses incurred by the public” (RegulationsGoverning the Use of Subaqueous Lands,Section 3.01(A), 5-7).

Some goals can be accomplished without anydredging. Creative analysis concerning the goalof the project can yield recommendations that willsatisfy the permit applicant’s needs withoutdredging. For example, a property owner wantingto dredge out a dilapidated boat slip filled withsilt might instead build a small pier directly intothe channel. In other instances, boaters could usewatercraft that can be accommodated with thecurrent channel depth, trailering larger boats toramps that access deeper waters. Commercialalternatives include the use of offshore terminals,not carrying the full capacity of cargo, coming intoport on high tide, “lightering” (offloading part ofthe load onto smaller barges at an area that canaccommodate the depth of the fully loaded carrier),or “topping off” (the reverse of lightering, fullyfilling a sea-bound carrier when it reaches the deepchannel).

In other cases, dredging is required to accomplishat least some of the desired outcome. However,even in this case, the quantity or area to be dredgedcan be minimized, management practices canreduce impacts, and post-project alterations canreduce the need for further maintenance dredging.

13


CHAPTER 2. ENVIRONMENTAL EVALUATION

Purpose

This section of the Dredging Policy Frameworkis designed to outline the required steps andmethods for evaluating the environmental effectsof dredging projects. It begins with use of existinginformation, field sampling, and modeling topredict impacts during the pre-dredge evaluation.The predicted impacts are verified and monitoredin the during-dredging evaluation, and then anylasting effects or long-term impacts would beexamined during a post-dredging evaluation. Inaddition, during this process, the applicant andreview agencies have an opportunity to developmeans to minimize, mitigate, or developalternatives so that a project can reach minimalenvironmental impacts.

This guidance is applicable to all proposeddredging and material disposal projects inDelaware waters. This includes private and stateprojects, as well as Federal projects conducted bythe U.S. Army Corps of Engineers.

PRE-DREDGE EVALUATION

This section describes the evaluation methods forprojects proposed in Delaware waters. It includesconsiderations of impacts both at the dredging siteand at the disposal site and examines potentialchemical, biological, and physical impacts. Thisevaluation protocol should be undertaken inconcert with required activities described in othersections of this document including alternativesanalysis, best management practices, andappropriate dredging and disposal methods.

The tiered approach in this section is consistentwith the Evaluation of Material Proposed forDischarge to Waters of the U.S. –Testing Manual

(Inland Testing Manual) (USEPA/USACE 1998),but provides guidance specifically for Delawareand includes evaluation methods for biological andphysical impacts. The reader is referred to thenational manual for a more detailed discussion ofthe tiered approach as applied to contaminants.

The objective of the tiered approach is to makeoptimal use of resources in generating theinformation necessary to make a determination,using an integrated chemical, physical, andbiological approach. To achieve this objective, theevaluation procedures are arranged in a series oftiers with increasing levels of intensity (Figure2.1). The initial tier uses available information thatmay be sufficient for completing the evaluationin some cases. Evaluation at successive tiersrequires information from tests of increasingsophistication and cost.

The most logical and cost efficient approach is toenter Tier I and proceed as far as necessary to makea determination. There are two possibleconclusions that can be made at each of the firstthree tiers: 1) available information is notsufficient to make a determination, or 2) availableinformation is sufficient to make a determination.Where information is sufficient, one of thefollowing determinations may be reached: a) theproposed project will not have unsuitable, adverseimpacts, or b) the proposed project will haveunsuitable, adverse impacts.

Tier I compiles existing information about thepotential for adverse impacts from the proposeddredging project. Operations that are excludedfrom further testing or evaluation should havehistoric data sufficient for the determination ormay proceed to a determination without additionaltesting.

15

Tier II evaluates the potential impacts on watercolumn and benthic environments using physical,chemical, and biological data collected for this tier,and applied with computer models to projectworst-case conditions for water quality impactsand bioaccumulation. Based on the results of TierII evaluations, additional evaluation may bereduced or eliminated.

Tier III evaluates the potential impacts on watercolumn and benthic environments using effects-based biological [testing]. This section presentsrecommended procedures for biological-effectstests with a standard group of organisms.

Tier IV is only entered if the information providedby Tiers I through III is not sufficient to make adetermination. The procedures used in Tier IV arekeyed to site specific issues not resolved by thestandardized procedures of earlier tiers.

With this tiered evaluation structure, it is notnecessary to obtain data for all tiers to make adetermination of potential impacts. The underlyingphilosophy is that only the data necessary to makea determination should be acquired. (See Figure2.1 for evaluations used at each tier)

Chapter 2. Environmental Evaluation

16


17

E v a lu a te E x is t in gIn fo r m a t io n ; (P o s s ib le

L im i te d T e s t in g fo rE x c lu s io n s )

M e a s u r e a n dM o d e l D is s o lv e d

C o n ta m in a n ts ;C o m p a r e to W Q S

C a lc u la teT h e o re t ic a l

B io a c c u m u la t io nP o te n t ia l ;

C o m p a re toR e fe re n c e

M e a s u r e T o x ic i ty ;M o d e l

S u s p e n d e dP h a s e , D e te r m in e

T o x ic i t y a f te rM ix in g

M e a s u r e T o x ic i ty ;M e a s u re

B io a c c u m u la t io n ;C o m p a re to F D A

L im it s ( ? )

C o n d u c t C a s e -S p e c i f ic T o x ic i ty

T e s ts

C o n d u c t C a s e -S p e c i f ic T o x ic i ty ;B io a c c u m u la t io n :

O th e r T e s ts

W A T E R C O L U M N B E N T H O S

T IE R I( G e n e r a l ly r e p r e s e n tse x is t in g in fo r m a t io n )

T IE R I I

T IE R I I I( T o x ic i ty a n d

b io a c c u m u la t io n te s ts )

T IE R IV( S p e c if ic b io a s s a y - -

to x ic i ty a n db io a c c u m u la t io n te s ts )

M o d e l E f fe c ts

R e c a lib ra teM o d e l, U s e

D if fe r e n tS c e n a r io s , F ie ld

V e r if y

C o n d u c t C a s e -S p e c i f ic F ie ldS a m p lin g a n d

A n a ly s is

M o d e l E f fe c ts ,F ie ld S a m p lin g

E x te n s iv e F ie ldS a m p lin g a n d

M o d e l V e r i f ic a t io n

C o n d u c t C a s e -S p e c i f ic S a m p lin g

a n d M o d e lin g

P H Y S IC A LL IV IN G R E S O U R C E S

F ig u r e 2 .1 . E v a lu a t io n s a t E a c h T ie r

Purpose

One of the purposes of Tier I ( See Figure 2.2) isto determine whether a decision regardingpotential impacts from a proposed project can bemade on the basis of existing information. Thecompilation of existing information about theexcavation and disposal sites will serve as the basisfor determining if a decision can be made withoutadditional evaluation. Another purpose of Tier Iis to identify potential contaminants of concern inthe dredged material. This will help determinewhat, if any, testing should be conducted insubsequent tiers.

In addition to contaminants, other potentialstressors should be identified and evaluated. Manyof these will depend upon the scale of the projectand the dredging and disposal method proposed.Stressors include habitat disturbances ordestruction, elevated turbidity related to dispersionof sediment at both the dredging and disposal sites,geotechnical properties of the sediments, solubleand particulate phase chemistry of excavatedsediments, and burial/smothering of biota at thedredging and disposal sites.

Interagency coordination is essential to thedevelopment of a 404(b)(1) CWA evaluation andis a legal requirement under the NationalEnvironmental Policy Act of 1969 (PL 91-190).Such coordination is critical in the Tier I evaluationprocess, where available information must becompiled from a variety of sources. Evaluators areencouraged to solicit input from other agencieson data sources, potential contaminants of concern,and proposed sampling and testing. Coordinationprior to initiation of sampling and testing willreduce the chance of having to repeat costlyprocedures and will assist in keeping projects onschedule.

Compilation of Available Information

The following questions should be answered bythe applicant after review of existing literature anddata sources. The questions should apply to theproject as a whole – addressing both excavationand disposal of the dredged material.

Chemical Information

A survey of contaminant sources and pathwaysshould be conducted for the proposed project. Anumber of factors must be considered, and thefollowing questions should be addressed to thefullest extent possible:

• What are the potential sources ofcontamination?

• What are the potential pathways ofcontaminant transport?

• What naturally occurring substances could beharmful to aquatic biota if resuspended orreleased?

• What are the seasonal ranges of dissolvedoxygen, and how would the proposed projectmodify these?

• What potentially harmful constituents couldbe part of the effluent from the disposal site?

• Will Delaware Surface Water QualityStandards be met in all cases?

Applicants must keep in mind that there are twocritical contaminant release pathways that couldincrease the local concentrations of contaminantsand potentially cause or significantly contributeto violations of Delaware’s Surface Water QualityStandards. The first release pathway occurs whencontaminants that are sequestered in the sedimentsbecome released directly to the water columnduring the excavation/dredging operation. Thesecond release pathway occurs when watercontaining dissolved and particulate contaminantsis released back into the waterway after thedredged material slurry has undergone dewateringin a confined disposal facility (CDF).

TIER I - PROJECT SCOPING

18


Figure 2.2. Tier I Flow Diagram

Evaluate ExistingInformation

Meets ExclusionaryCriteria

InformationSufficient for

Determination

Evaluate Compliance WithWQS

Further Testing AndEvaluation

Yes

Yes

No

No

19


Biological Information

Data regarding living resource impacts should alsobe gathered. The following specific informationwill aid in evaluating biological impacts from theproject and should be collected if at all possible:

• Are there species of special concern to stateor federal management agencies?

• Are there Threatened or Endangered speciesin the vicinity of the site?

• Do commercially or recreationally importantfish or shellfish use the area for habitat?

• What organisms, that are important to the foodchain or are habitat modifiers, exist nearby?- What are the lifestages of

organisms identified above?- What time of year do they utilize

the site and for how long do theyremain in the area?

- What potential impacts(entrainment, smothering, habitatdestruction, contamination) fromdredging or disposal could affectthese organisms?

• What is the vegetation distribution?• Are there migratory corridors nearby?

The lists of threatened and endangered species,commercially important species, and species ofspecial concern can be found in Appendix C.

Physical Information

The following information concerning physicalimpacts from the project should be collected tothe fullest degree possible:

• What is the sediment type (composition andgrain size) in the project area?

• What is the particle size distribution (sieveanalysis results)?

• What best characterizes the material in termsof percent solids?

• What is the ambient turbidity and how wouldthat be affected by the project? How longwould the duration of any turbidity increase

be expected to last?• Describe (and provide a map) of the excavation

site bathymetry.• Describe (and provide a map) of the disposal

site bathymetry (if applicable).• Describe the hydrologic regime of the region

around the project site.• What past or current projects have taken place

in the vicinity?• Where are nearby groundwater aquifers

located?• Is there a potential for groundwater

contamination?• What is the upland topography of the proposed

disposal site (if applicable)?

For additional information needed for routinedredging projects, applicants should refer to thePermit Application Form (formerly known as JointPermit Application From) for Subaqueous Lands,Wetlands, Marina, and 401 Water QualityCertification Projects. This form can be found inthe Appendix D of this document and is availablefrom the DNREC, Division of Water Resources.

Sources of Information

There is a potentially large amount of historicalinformation relevant to dredging projects availablefrom Federal, state, and local agencies, as well asin the open literature. Sediment quality data areroutinely collected by the USACE at the sites oftheir dredging projects (i.e. Delaware River MainChannel, C&D Canal, Port of Wilmington). Muchof this database is physical and chemical data withsome biological test results. Sediment data has alsobeen collected by other agencies and investigators.

A number of computer databases are maintainedby federal agencies that contain information onknown sources of chemical contamination. Thesedatabases include: STORET (STOrage andRETrieval system), TRI (Toxic Chemical ReleaseInventory), PCS (Permit Compliance System),RCRIS (Resource, Conservation, and RecoveryAct Information System), ESDC (EnvironmentalSciences Division Clearinghouse), and GRIDS


20

(Geographic Resources Information and DataSystem). Some of these can be accessed directlyvia the internet.

Additionally, there are state sources of waterquality data that can be found by contacting theDNREC, Division of Water Resources. Biologicaland physical information for Delaware can befound by contacting the DNREC, Division of Fish& Wildlife or the Delaware Geological Survey,respectively.

Exclusions from Evaluation under the TierSystem

If an evaluation of the extraction (dredging) siteindicates that the material to be dredged is not a“carrier of contaminants,” the determination of thepresence or effects of contaminants can be madewithout further evaluation and testing. Dredgedor fill material is most likely to be free fromchemical, biological, or other pollutants where itis composed primarily of sand, gravel, and otherinert materials. However, a determination of “nocontaminants” may still not exclude the projectfrom being subject to evaluation for otherchemical, physical, or biological effects.

Other criteria that may qualify a project forexclusion would include projects involving lessthan 50 cubic yards of excavated materials andprojects where dredged material is placed into anexisting, approved disposal site.

Dredged material that are most likely to meet thisexclusion include sediments from locations whichare far removed from most anthropogenicactivities or sediments from depths deposited inpre-industrial times and not exposed to modernsources of pollution. However, the potentialimpacts from natural mineral deposits should alsobe considered.

Identification of Contaminants of Concern

The purpose of identifying contaminants ofconcern in dredged material is to determine

parameters for evaluation in later tiers, ifnecessary. A contaminant of concern should beidentified on the basis of the following factors:presence in the dredged material, concentration,toxicological importance, persistence in theenvironment, propensity to bioaccumulate fromsediments, and presence of applicable fishconsumption advisory.

Table 2.1. Generic list of chemicals of concernfor characterizing sediments

This generic list of contaminants of concern shouldserve as a starting place and not necessarily as thefinal list. Information compiled on a specificproject, as described above should be used tosupplement or reduce the chemical parameters onthe generic list. The reasons for supplementing orreducing this list should be fully documented.

In situations where there are fish consumptionadvisories, the responsible bioaccumulative


21

ArsenicChromiumCopperMercuryZincPesticidesTotal Organic Carbon (TOC)Total volatile solids (TVS)Ammonia-nitrogenTotal petroleum hydrocarbons (TPH)Polychlorinated biphenyls (PCBs)Polyaromatic hydrocarbons (PAHs)CadmiumTotal phosphorousLeadDioxinsNickel

contaminants that are the source of the advisoryshould be considered for the list of contaminantsof concern. A summary of recent State fishadvisories and a listing of State agency contactscan be obtained from the DNREC, Division of Fishand Wildlife.

Potential Impacts Determination

After consideration of all available information,one of the following two possible conclusions canbe reached at Tier I:

1. Existing information does not provide asufficient basis for making a contaminantdetermination. In this case, the applicant maybe directed to gather additional information atthe Tier I level which could substantiate adetermination, or they will be directed toengage in further evaluation at a higher tier asappropriate.

2. Existing information does provide a basis formaking a contaminant determination. In thiscase, one of the following threedeterminations may be reached:a) The dredged material meets the exclusion

criteria and no further information oncontaminants is necessary to determinecompliance (except for informationnecessary for Section 401 compliance).

b) The dredged material does not complywith the exclusion criteria, but the availableinformation is sufficient to show thematerial is not a carrier of contaminationto a degree which will cause an unsuitable,adverse impact.

c) The dredged material does not complywith the exclusion criteria, and theavailable information is sufficient to showthe material is a carrier of contaminationto a degree which will cause an unsuitable,adverse impact.

For projects with recurring maintenance dredging,a Tier I evaluation is not necessarily required foreach dredging and discharge operation. Acomprehensive Tier I evaluation should require

only updating on a periodic basis to determine ifadditional data or evaluation is necessary. Thisreevaluation of the Tier I analysis should consistof the collection and examination of availableinformation on any changes in contaminantsources or pathways to the dredging and dischargesites. It is recommended that the Tier I evaluationbe updated at least every three to five years forfrequently dredged projects and prior to eachoperation for projects dredged less frequently.

At the completion of Tier I, even if an exclusionis approved or it is decided that existinginformation is sufficient to make a determination,additional testing may be necessary to obtain acertification of water quality compliance, asrequired under Section 401 of the Clean WaterAct.

Reporting

The report of the Tier I evaluation shouldsummarize the following information:

• potential sources of sediment contaminationidentified,

• sources of information investigated,• history of dredging in the area,• selected method of dredging and disposal,• historic sediment data (physical, chemical,

biological),• contaminant pathways to dredging and

discharge sites,• reasons for applying exclusions from testing,• timing of project and any time of year

restrictions,• results of any confirmatory testing,• contaminants of concern list,• benchmarks or other criteria for biological,

physical, or chemical data,• reasons for the final list of contaminants of

concern,• habitat present and potential for its

disturbance,• potential for wildlife exposure,• monitoring plans,• impact area – any acute or chronic effects,


22

• potential for secondary impacts,• source reduction efforts,• Quality Assurance/Quality Control

documentation supportive of critical data

All data should be submitted in digital format aswell as in printed form, if applicable. Allmeasurements should be recorded in dry weight.

This documentation should be developed into areport that can be distributed for State and Federalagency review and if necessary, inserted as anappendix to the 404(b)(1) evaluation public reviewdocument. A well documented Tier I evaluationwill expedite future 404(b)(1) evaluations for thesame project or any new dredging projects in thevicinity.

Purpose

The purpose of Tier II (See Figure 2.3) is to usephysical, biological, and chemical data collectedfor this tier as well as calculations and models toprovide a reliable, rapid screening tool todetermine potential impacts. It is also designed todetermine whether more costly biological effects-based testing is necessary.

There are two situations under which a project willbe evaluated under Tier II.1) Having completed Tier I with insufficient

information to reach a determination.2) Having completed Tier I with sufficient

information for a contaminant determination,but requiring additional data for Section 401Water Quality certification. The testing in TierII will provide information necessary todetermine water quality compliance forSection 401 and may reduce the scope of futuretesting.

Planning and Coordination

The purpose of sediment sampling and analysis

in Tier II is to obtain the necessary physical,chemical, and biological data for evaluatingpotential water column and benthic impacts. Thesampling should take into consideration impactsfrom the project as a whole – both at the excavationsite and at the material disposal location. Theinformation gathered in Tier I should, in mostcases, be adequate to determine the scope ofsediment sampling and analysis as well as thechemical parameters of concern.

Evaluations should include predictions ofcontaminant concentrations expected in the mixingzone surrounding the excavation, in the mixingzone of the disposal site, and after complete mixingwith the waterway. The near-field predictionsshould be compared to aquatic life criteria and thecomplete mix concentrations should be comparedto human health criteria.

It is recommended that a written plan for sedimentanalyses or field sampling be prepared andprovided to the appropriate Federal and Stateagencies for coordination prior to sampling. Thiscoordination will reduce the chance of having torepeat costly procedures and will assist in keepingprojects on schedule. The informationrecommended for submission to the DNRECincludes the following:

• Summary of Tier I results;• Objectives of Tier II review;• Sampling protocols (type of sample, number,

location, method of sample, QA/QC, etc.);• Laboratory methods (handling, preservation,

storage, QA/QC, etc.);• Data assessment methodology;• Sampling schedule.

Sampling Methods and Locations

Standards and methodology for appropriatesampling and field survey techniques can be foundin the USACE/USEPA Inland Testing Manual.Sediment sampling plans are so site specific thatguidance on the number, type, and location ofsamples is necessarily quite general.

TIER II - PHYSICAL AND CHEMICAL TESTING


23

Tier I

Evaluate WaterColumn Impacts

Evaluate BenthicImpact

Sediment BulkChemistry

Elutriate TestResults

Sediment BulkChemistry

Addams Model Addams ModelTBP Analysis

ModeledConcentrations

Exceed WQS AfterConsidering Mixing

PotentialInteractive

EffectsTBP Analysis ofDredged MaterialExceeds Criteria

DischargeWill Not

Meet WQS

DischargeWill Meet

WQS

Proceed toTIer IIIWater

ColumnToxicityTests

Potential forBioaccumula

tion.Proceed toTier III forTesting

NoBioaccumula

tionPotential

Proceedto Tier III

forBenthicToxicityTesting

Yes No Yes Yes No

Figure 2.3. Tier II Flow Diagram

Evaluate LivingResourceImpacts

UnacceptableImpacts

NoUnacceptable

Impacts

UnacceptableImpacts

24


In any sampling program, a finite number ofsamples are used to represent some larger area orvolume, possibly with some consideration of time.Factors that should be considered in selecting thenumber, type and locations of sediment samplesinclude: distribution of sediments to be dredged,known or suspected contaminant distribution,dredging methods, disposal methods, and tests tobe performed.

Physical, Chemical, and Biological Analyses

Guidance on laboratory procedures for physicaland chemical analysis of sediments is provided inthe USACE/USEPA Inland Testing Manual. Anyvariation from these procedures should becoordinated with the USACE District, USEPARegion 3, and the DNREC.

Also included in the above document are theaccepted procedures for the preparation andchemical analysis of an elutriate. The elutriate test(USACE 1976) is a procedure developed tosimulate the release of dissolved contaminantsfrom a hydraulic dredged disposal operation inopen waters, and may be considered a worst caseanalysis for the release of dissolved contaminantsfrom a mechanical dredged disposal operation.The elutriate test is used to evaluate water qualitycompliance for Section 401 certification. Elutriateconcentrations should be reduced to reflectdilution resulting from mixing and dispersion atthe proposed disposal site.

Field surveys for benthic and pelagic organismsshould be coordinated with DNREC, Division ofFish & Wildlife or Division of Water Resources.

Quality Assurance

Quality assurance (QA) is a critical element withinany 404(b)(1) contaminant evaluation. Theimportance of QA is not limited to the laboratory,but extends throughout the evaluation. General QAguidance and the data quality objectives (DQOs)for dredged material testing and evaluation areprovided in the Inland Testing Manual.

Living Resource and Benthic Impact Evaluations

The evaluation of living resources andcommunities begun at the Tier I level shouldcontinue in Tier II. Where data collected in Tier Iwas inadequate to determine potential effects,sampling projects should be developed andinitiated. The sampling protocol should take intoaccount seasonal variations and distributionalconsiderations, and all sampling proposals shouldbe coordinated with DNREC.

One objective of the Tier II benthic evaluation isto determine if dredged material contaminantshave the potential to cause an unacceptable adverseimpact on benthic organisms, or on other aquaticorganisms through bioaccumulation. This tier usessediment chemical data with calculations and/ormodels to predict potential benthic andbioaccumulation impacts.

Benthic invertebrates constitute a major biologicalcomponent of aquatic ecosystems. The benthicfauna serve as important forage sources forestuarine fish, waterfowl, and larger invertebrates.As such, benthic invertebrates represent a principallink between the primary producers and higherlevel consumers. In addition, the benthos exertmajor influences on the flux of materials acrossthe sediment-water interface, playing principalroles in nutrient recycling, sedimentation,sediment chemistry and oxygen dynamics.Because of their limited mobility, benthicinvertebrates are particularly vulnerable to localchanges in water and sediment quality, as well as,modifications to habitat due to such activities asdredging.

Potential for Bioaccumulation

Bioaccumulation is the uptake and retention ofcontaminants by organisms. In aquatic systems,sediment contaminants may bioaccumulate tolevels having ecological and human healthconsequences. Not all sediment contaminants willbioaccumulate. Some are readily metabolized, or


25

degraded, within the organism’s body. Others aresimply not taken up. A listing of critical pollutants,some of which are bioaccumulative, is providedin Table 2.1 in the Tier I text.

The following factors should be considered todetermine which (if any) contaminants should beevaluated for bioaccumulation potential: presencein the dredged material, propensity tobioaccumulate from sediments, and presence ofapplicable fish consumption advisories.

The currently available Tier II procedure forevaluating potential benthic impact consists ofevaluating the Theoretical BioaccumulationPotential (TBP). A comparison is made betweenthe TBP calculated for the nonpolar organiccontaminants of concern in dredged material andfor the same constituents in the reference sediment.At present, this calculation can be performed fornonpolar organic compounds, but not for polarorganic compounds, organometals, or metals. Ifsuch constituents are contaminants of concern ina dredged material requiring bioaccumulationevaluation, further evaluation must take place inTier III.

Water Column Impact Evaluations

Another objective of the Tier II evaluation is todetermine if the dredged material contaminantswill cause an unacceptable adverse impact onorganisms within the water column and complywith applicable water quality standards, usingchemical data. The dredging and dischargeoperation cannot cause the Water QualityStandards to be exceeded outside the mixing zone.There are two primary pathways for toxicsubstances to be available to aquatic life. The firstroute would be at the point of excavation whenthe dredge head disturbs sediments. As thesediment is resuspended, some substancepreviously sorbed to particles could dissolve andbe available in the water column. The secondpathway for toxic substances to be available toorganisms would be in the dewatering effluent atthe confined disposal facilities.

Contaminant Mobilization at the Point of Dredging

Equilibrium Partitioning Theory is a mathematicalmethod of estimating the proportion of a chemicalbound to sediment to the chemical dissolved inwater. When the concentration of chemical perunit weight of sediment and the total weight ofthe sediment are known, then using this method,the concentration of the chemical in the water canbe calculated. Multiplying the bulk sedimentconcentrations by the expected total suspendedsolids (TSS) level will yield the sorbedconcentrations in the water column. Once thesorbed pollutant concentration in the water columnhas been calculated, the amount of pollutant thatleaves the particulate phase and becomes dissolvedin the water column may be calculated. Thedissolved concentrations of various constituentsin the water column should be compared withapplicable water quality criteria.

An elutriate test (in which sediment and water aremixed and contaminant concentrations aremeasured in the water after allowing the sedimentto settle out) can be used to gather furtherinformation or to verify the EquilibriumPartitioning approach above. In some cases, theelutriate test may be more accurate since it usesactual observations; however, each method isconsidered to yield a fairly conservative estimateof potential to water quality impacts or effects toaquatic life (Versar, 2000).

Modeling Confined Disposal Facility Discharge

The most common disposal method used inDelaware is the upland confined disposal facility(CDF). As the material placed in the site beginsto dry, water is discharged into the adjacent surfacewater over a weir used to control the rate ofdischarge and to maximize the retention ofsediments in the site.

A mixing zone is used to evaluate the geographicalrange of the impacts from CDF runoff. The mixing


26

zone is the limited area or volume where the initialdilution of a discharge occurs, and water qualitystandards must be met at the edge of the zone ratherthan within it. The standards for mixing zonecalculations can be found in the Delaware SurfaceWater Quality Standards.

The Cornell Mixing Zone Expert System(CORMIX) is a software package with a series ofmodules for the analysis, prediction, and designof aqueous toxic or conventional pollutantdischarges into diverse water bodies. The system’smajor emphasis is on predicting the geometry anddilution characteristics of the initial mixing zoneso that compliance with acute and chronicregulatory constraints can be evaluated. TheEPA’s CORMIX distribution page is ftp://ftp.epa.gov/epa_ceam/wwwhtml/softwdos.htm.The CORMIX-GI homepage is http://steens.ese.ogi.edu; this is the most useable versionof the model and has Windows interface forinteracting with the model. By modeling theplume behavior, CORMIX can be used to evaluatehow the effluent will dilute in the ambient waterunder a variety of conditions.

Section 401 Certification

Section 401 of the Clean Water Act requires thatany applicant for a 404 permit must provide thepermitting agency a certification from the Statethat the discharge complies with applicable Statewater quality standards. Part 230.10 (a)(5)(b) ofthe Code of Federal Regulations states that, “Nodischarge of dredged or fill material shall bepermitted if it: (1) Causes or contributes, afterconsideration of disposal site dilution anddispersion, to violations of any applicable Statequality standards.”

Other Considerations

In the absence of site-specific data on exposurerisks, information about impacts can be obtainedfrom guidance literature. This includes modelingof the predicted dredged material footprint andplume dispersion modeling, contaminated

sediment transport modeling, modeling of thetoxicity and bioaccumulation potential of benthicorganisms exposed to contaminants data onsurvivorship of planktonic/nektonic organismsexposed to elutriates of contaminated sediments,data on the critical burial depth of smotheredbenthos, results of studies on the effects ofsuspended silt on impacts on both planktonic andbenthic organisms, regional data on seasonalspawning, larval settlement, and migration ofspecies-of-interest, or generic features of benthicsuccession following dredging and disposal.

Physical, chemical, and biotic data gaps may befilled using existing information, or the existinginformation can be amended with field sampling.The following describe some data gaps that couldbe supplemented in Tier II.

Physical data gaps may include information aboutthe distribution of sediment types, hydrologic/hydrographic setting (currents, waves, tides,overall kinetic energy, salinity regimes, seasonalwater column stratification and hypoxia),predicted dredged material thickness over thedredged material footprint, predicted plumedispersion, and overall sediment transport.

Some chemical and biochemical data gaps canpotentially be addressed by reviewing regionalsediment quality databases, with identification ofspecific contaminants of concern and theirassociation with particular sediment types (organiccontent, grain-size, mineralogy).

Biotic data gaps include a regional review ofcritical ecosystem components that are likely tobe exposed to risk. Impacts can be genericallypredicted by referring to existing literature on theresponse of exposed organisms to organiccontaminant loading in bottom sediments,survivorship of water column organisms exposedto elutriates, tolerance of different species tosuspended solids loadings, and predictedresponses of benthos to burial, smothering, andexpected rates of recolonization.


27

If a literature search in Tier I was inconclusiveregarding the presence of species of interest, fieldsurveys should be employed in Tier II. This wouldinclude benthic grabs, trawls, etc. These samplingevents should take into consideration theseasonality of the species in question and shouldbe properly coordinated and permitted through theDNREC, Division of Fish & Wildlife. Theinformation gathered from the sampling shouldbe used to enhance the answers to the questionslaid out in Tier I.

Impacts Determination

After consideration of all available information,one of the following two possible conclusions canbe reached at Tier II:

1. Existing information does not provide asufficient basis for making a contaminantdetermination. In this case, further evaluationat Tier III is appropriate.

2. Existing information does provide a basis formaking a contaminant determination. In thiscase, one of the following two determinationscan be reached:a) The proposed dredged material discharge

will not cause unsuitable, adverse,contaminant-related impacts.

b) The proposed dredged material dischargewill cause unsuitable, adverse,contaminant-related impacts.

The current state-of-the-art technology willprovide adequate information for a contaminantdetermination at the end of Tier II in only a limitednumber of situations. If the only cause forproceeding into Tier II was the presence of a singlecontaminant, of which the toxicology andbioaccumulation potential are well understood, adetermination may be completed in Tier II. Inaddition, if Tier II testing was performed solelyfor determining 401 compliance, a determinationmay be completed here.

Reporting

All data should be submitted in standard,electronic format. The DNREC will requireroughly forty-five days to review the data andreport submission. Comments from DNREC willbe returned to the applicant about forty-five daysafter the time of submission unless otherwisenegotiated with the applicant.

Information gathered under Tier I and Tier II mustbe summarized and condensed in the 404(b)(1)evaluation document. Because a comprehensivetiered evaluation will likely gather far moreinformation than can be presented in the 404(b)(1)evaluation, and because of the importance of thedecisions made at this tier, it is recommended thatthis information be documented and filed as abackup to the 404(b)(1) evaluation. Thisdocumentation should be developed into a reportthat can be distributed for State and Federal agencyreview and if necessary, inserted as an appendixto the 404(b)(1) evaluation public reviewdocument.

A summary of the results from Tier II analysisshould include the following, along with thesummary of results developed from the Tier Ianalysis discussed above:

• Sampling results of sediment bulk chemistryand physical testing program;

• QA/QC documentation;• Water column impact evaluations (where

appropriate), including water quality screen/model results, or elutriate/model results;

• Mixing zone determination; and• Benthic impact evaluations, including list of

potentially bioaccumulative contaminants,TBP calculation results, and evaluation of non-hydrophobic, bioaccumulative contaminants.

28


Purpose

The purpose of Tier III is to make impactdeterminations through the use of effects-basedbiological tests or field verifications of modeledeffects (See Figure 2.4). The testing in Tier IIIassesses the impacts of dredging and disposaloperations on appropriately sensitive andbenchmark organisms to determine if there is thepotential for an unacceptable (toxicity orbioaccumulation) impact. Biological evaluationsserve to integrate the chemical and biologicalinteractions of the suite of contaminants whichmay be present in a dredged material sample,including their availability for biological uptake,by measuring their effects on test organisms.


Planning and coordination is needed in all stagesof a 404(b)(1) evaluation, but the need is especiallycritical in Tier III because of the high costs ofbiological effects testing. For most dredgingprojects, these high costs will necessitate that eachsample represent a larger portion (e.g.,management unit) of the area to be dredged.Coordination with other agencies conducted inearlier tiers should be continued in Tier III. Awritten plan for sediment sampling and analysesshould be prepared and provided to the appropriateFederal and State agencies for coordination priorto sampling.

Sediment Sampling

Detailed guidance on acceptable sedimentsampling methods and procedures is provided inthe Inland Testing Manual (USACE/USEPA,1998). Included in this document is informationon acceptable sediment collection and handlingprocedures. Also included is guidance on how toplan and execute a sampling program. Sedimentsampling plans are so site specific that guidance

Effects-Based Tests

The Tier III assessment methods are bioassays(toxicity and bioaccumulation tests). Guidancefor these tests can be found in the USACE/USEPAInland Testing Manual and in the USEPA Short-Term Methods for Estimating The ChronicToxicity of Effluents and Receiving Waters toMarine and Estuarine Organisms.

Effects-based biological tests are laboratoryprocedures (bioassays) in which organisms areexposed to a contaminated medium. Most of thewater quality standards and criteria for specificcontaminants were developed from effects-basedtests. These types of tests used direct exposuresof organisms to known levels of a singlecontaminant. Example of test exposures include amouse fed a contaminant in its food, or a fishplaced in a tank with the contaminant dissolvedin its water. The biological effects which may bemeasured by such tests include mortality (death)of the organism, growth, reproduction, and others.

The type of organism, exposure media, exposureconditions, and measured effects or end-points areall specific to the questions being addressed. Ingeneral, three sensitive species are recommendedfor the water column and whole sediment toxicitytests. In the case of the latter, two species can beused, provided they cover three functionalcharacteristics: filter feeder, deposit feeder,burrower. In both cases, at least one of thesespecies must be a sensitive “benchmark” species.For assessing bioaccumulation, adequate tissuebiomass and the ability to ingest sediments is moreimportant than taxon sensitivity. Where possible,two species should be used to assess the potentialbioaccumulation unless adequate regional data areavailable to justify single species testing.

Biological-effects tests for dredged material

on the number, type, and location of samples isnecessarily quite general. The guidance providedin the Tier II description is generally applicable


29

TIER III - BIOLOGICAL TESTING

Tier I/II

Evaluate Water ColumnImpacts Evaluate Benthic Impacts

Water Column ToxicityTests Benthic Toxicity Tests Benthic Bioaccumulation

Tests

InformationSufficient for

Determination

Unsuitable Contaminant-Related Impacts

No UnsuitableContaminant-Related

ImpactsTier IV

Yes No

Figure 2.4. Tier III Flow Diagram

30


testing and evaluation must represent the physicaland chemical conditions of contaminant exposureduring dredging and disposal. For a 404(b)(1)evaluation, there are two exposure conditions tobe tested; water column and benthic. The watercolumn exposure is directed at the impacts ofcontaminants released into the water from dredgedmaterial as they are discharged and settle to thebottom. The benthic exposure is directed at theimpacts of contaminants deeper in the bottomprofile and at the disposal site (if open water).

The USEPA and USACE have developed effects-based biological tests for dredged materialevaluation. They include water column tests,which utilize sediment elutriate preparations andbenthic tests, which utilize whole sediment as testmedia. Complete methodologies for the tests areprovided in The Great Lakes Dredged MaterialTesting and Evaluation Manual (USACE/USEPA,1998). Guidance on species to be used andappropriate methodology can be found in theInland Testing Manual (USACE/USEPA, 1998)and in the Short-Term Methods for Estimating TheChronic Toxicity of Effluents and ReceivingWaters to Marine and Estuarine Organisms(USEPA, 1994).

Quality Assurance

Quality assurance is a critical element in all tiersof a contaminant evaluation. General QA guidanceand the data quality objectives for testing andevaluation is provided in the Inland TestingManual.

Benthic Impact Evaluations

The Tier III benthic evaluation will determine ifdredged material contaminants have the potentialto cause an unacceptable adverse impact onbenthic organisms. Two benthic toxicity tests andone benthic bioaccumulation test have beendeveloped.

Benthic Toxicity Tests

The specific methodologies for data generation,sampling, and laboratory procedures can be foundin Section 11 of the Inland Testing Manual(USACE/USEPA, 1998). Species selection shouldtake into consideration the unique characteristicsof the potential dredged site and the region, andthis selection as well as all other methodologychoices should be coordinated with arepresentative from the DNREC. An overview ofthe procedures is provided here for generalreference.

Benthic toxicity tests are conducted by placing thetest organisms into small beakers which are filledwith water and have a layer of the test sediment atthe bottom. The water overlying the sediment isrenewed periodically. Organisms are fed duringthe exposure. The tests are completed in ten days,at which time the organisms are examined forresponse.

These toxicity tests have been developed tomeasure lethal or sublethal responses. The lethalresponse is measured as mortality or survival oforganisms. The sublethal response measured isgrowth. The results of these toxicity tests for thedredged material and the control site sediment arecompared statistically for the contaminantdetermination.

The results of the benthic toxicity tests must firstbe evaluated in light of the QA objectivesdescribed above. If the responses of organisms incontrol exposures are within acceptable limits, thetest results with the dredged material and thedisposal site sediment may be evaluated using thestatistical methods described in the Inland TestingManual (USEPA/USACE 1994).

Dredged material is considered not to meet thetesting Guidelines when:

1. the mortality of test organisms exposed to thedredged material is more than 10 percentgreater (20 percent for C. tentans) than the


31

mortality of test organisms exposed to thecontrol site sediment or

2. when the mean weight of organisms exposedto the dredged material is more than 10 percentless than the mean weight of organismsexposed to the control site sediment,

and is statistically different at the 95 percentconfidence level.

If the results of any of these evaluations arenegative, the dredged material discharge isconsidered not to meet the Guidelines. If negativetest results are suspected to be the result of non-contaminant impacts, additional benthic toxicitytesting using sublethal end points or otherorganisms may be considered in Tier IV.

Benthic Bioaccumulation Test

The methodology for the benthic bioaccumulationtest with Lumbriculus variegatus is detailed in theGreat Lakes Dredged Material Testing andEvaluation Manual (USACE/USEPA, 1998) . L.variegatus is a freshwater oligochaete worm(aquatic earthworm) that is 1-1.5 mm in diameterand 40-90 mm long. It burrows in sediments, isan important food item for bottom feeding fish,and is commonly cultured and harvested for fishfood in pet stores. Other species that may beappropriate for bioaccumulation testing as well asmethodology for the test can be found in Section12 of the Inland Testing Manual (USACE/USEPA, 1998).

The benthic bioaccumulation test is conducted by

32

Table 2.2. Effects-based biological tests (for Tier III evaluation)

Freshwater Species Test Type1 Endpoint(s) Test Duration (days)2

Daphnia magna E Survival/Survival and reproduction 2/21Ceriodaphnia dubia E Survival/Survival and reproduction 2/7Pimephales promelas E Survival/Survival and growth 4/7Chironomus tentans S Survival and growth 10Hyalella azteca S Survival and growth 10Lumbriculus variegatus S Bioaccumulation 28

Estuarine/Marine Test Type1 Endpoint(s) Test Duration Species (days)2

Cyprinodon variegatus E Survival and growth 7Menidia beryllina E Survival and growth 7Mysidopsis bahia E Survival, growth and fecundity 7Arbacia punctulata E Fertilization 1 hr. 20 min.Champia parvula E Reproduction 7-9

1 Elutriate (E) or Solid phase (S)2 Only short-term tests recommended for Tier III application


placing a large number (500-1000) of organismsinto a 5.5 liter aquarium with a layer of sedimentand overlying water. The water is renewedperiodically, but the organisms are not fed duringthe exposure (other than organic matter already inthe sediments). The tests are completed in 10-28days, at which time the organisms are preparedfor chemical analysis.

Benthic bioaccumulation testing is not necessaryif the proposed dredged material has nobioaccumulative contaminants of concern (asdetermined in Tier 1) or if the TBP analysisconducted in Tier II conclusively indicates thatthere is no potential for bioaccumulation ofcontaminants relative to the disposal site sediment.

If the contaminant of concern list for the dredgedmaterial includes bioaccumulative contaminants,and if analysis for potential bioaccumulationconducted in Tier III was inconclusive, the dredgedmaterial should be tested using the benthicbioaccumulation test. The results ofbioaccumulation tests with the dredged materialare compared statistically to the results with thecontrol site sediment.

Dredged material is considered not to meet theGuidelines when the mean concentration ofbioaccumulative contaminant(s) in test organismsexposed to the dredged material is statisticallygreater than the concentration of thesecontaminant(s) in test organisms exposed to thedisposal site sediment.

Water Column Impact Evaluations

The Tier III evaluation will determine if thedredged material contaminants cause anunacceptable adverse impact on organisms withinthe water column. Water column toxicity tests(elutriate-based tests) have been developed for thisTier. A list of species appropriate for these testsas well as guidance for their selection can be foundin Section 11 of the Inland Testing Manual(USACE/USEPA, 1998).

Water column toxicity tests use elutriatepreparations prepared by mixing sediment andwater (on a 1:4 ratio) into a slurry. The slurry isallowed to settle and the supernatant decanted. Thesupernatant is then centrifuged to removesuspended particles. This supernatant is theelutriate, which is diluted in series and used as thetest solution for water column toxicity tests.

The test organisms are exposed to the elutriate inbeakers or small aquaria. The elutriate is renewedperiodically and the organisms are fed during theexposure. The elutriate tests were developed tomeasure lethal and sub-lethal responses, withshort-and long-term exposures. The D. magna testsare completed in two (short-term) or twenty-one(long-term) days. The C. dubia tests are run intwo or seven days, and the P. promelas test inseven or twenty-one days. The lethal response ismeasured as mortality or survival of organisms.The sublethal response measured is reproductionfor D. magna and C. dubia and growth for P.pimephales. The results of these toxicity tests forthe dredged material are evaluated to determine ifan unacceptable toxicity risk will occur outsidethe mixing zone.

One potential cost-saving measure during theimplementation of water column tests that mightbe considered is to perform the test only with thefull-strength elutriate, and not conduct the dilutionseries. Experience with similar tests and marinesediments has shown that undiluted elutriatesinfrequently produced mortality greater than 50percent. While it must be recognized that there isa risk of having to repeat the test, the potentialcost-savings outweigh this risk in most cases.

The results of the water column toxicity test mustfirst be evaluated in light of the QA objectivesdefined earlier in this section. If the responses oforganisms in control exposures are withinacceptable limits, the test results with the dredgedmaterial may be evaluated using the statisticalmethods in the “Inland Testing Manual” (USEPA/USACE 1998) and the water quality screen modelemployed in Tier II.

33


Dredged material is considered not to meet theGuidelines when the concentration of dredgedmaterial contaminants at the boundary of themixing zone statistically exceeds 0.01 of theconcentration (LC) causing 50 percent mortalityof test organisms exposed to the dredged materialelutriate. The screening model is used to calculatethe dilution of the elutriate within the mixing zone.

Other Considerations

Tier III concentrates on linking observedcharacteristics in the water column and benthicenvironments to potential impacts on livingresources. Therefore, it involves the integrationof the chemical, biological, and physical datacollected. In addition to the bioassay tests, it maybe necessary to do field verification tests of theeffects modeled in Tier II. For example, ifsmothering of benthic organisms is a concern, inTier II the applicant would have run a model topredict the potential for sedimentation. In a TierIII extension, the applicant would actually deploysediment traps into the water near the dredge siteand determine the actual and stochasticsedimentation rates.

New physical data requirements may includebathymetry baseline data, wave and currentclimate, sediment transport, or ambientsedimentological conditions. Field measurementsof transient plume behavior may also be includedin such a field survey.

Additionally, biological information from tissueanalysis for indigenous species may be necessaryin order to determine background levels of toxicburden or presence of contaminants of concern.New data on ambient distribution of benthic,planktonic, nektonic, and demersal species at thedredging site (or disposal site) may be required.

Impacts Determination

After consideration of all available information,one of the following two possible conclusions canbe reached at Tier III:

1. Existing information does not provide asufficient basis for making an impactsdetermination. In this case, further evaluationat Tier IV may be appropriate.

2. Existing information does provide a basis formaking an impacts determination. In this case,one of the following determinations can bereached:a) The proposed dredging and disposal will

not cause unsuitable, adverse impacts.b) The proposed dredged material discharge

will cause unsuitable, adverse impacts.

The information obtained in Tier III and earliertiers should be sufficient to reach a determinationin almost all cases. Therefore, the first conclusion(information not sufficient) should be reached onlyin unusual circumstances.

Reporting

Information gathered during Tiers I, II and III mustbe summarized and condensed in the 404(b)(1)evaluation document. Because a comprehensivetiered evaluation will likely gather far moreinformation than can be presented in the 404(b)(1)evaluation, and because of the importance of thedecisions made at this tier, it is recommended thatthis information be documented and filed as abackup to the 404(b)(1) evaluation. Thisdocumentation should be developed into a reportthat can be distributed for State and Federal agencyreview and if necessary, inserted as an appendixto the 404(b)(1) evaluation public reviewdocument.

Purpose

The purpose of Tier IV is to make determinationsthrough the use of case-specific testing andevaluation. It is anticipated that the informationobtained from testing and evaluations in Tiers I,II and III will not be sufficient for a contaminant

TIER IV - CASE-SPECIFIC TESTING

34


determination in very few cases. For example, TierIV testing may be appropriate where Tier III testresults are conflicting or inconclusive.

In these rare cases, testing procedures that havenot been adopted for regional application, andthose that are more research-oriented may beemployed, as necessary. Because any testing andevaluation conducted in Tier IV is entirely case-specific, limited guidance can be offered. Further,it must be recognized that Tier IV is not aninvitation to conduct basic research, but amechanism for obtaining the informationnecessary to address case-specific dredgedmaterial contaminant impacts.

Tier IV testing should be focused on issues notresolved in earlier tiers. If Tier III testing for watercolumn toxicity and benthic bioaccumulation wereconclusive but the benthic toxicity testing was not,Tier IV testing should be limited to the unresolvedbenthic toxicity impacts of dredged materialcontaminants. Similarly, if Tier III testingproduced conclusive determinations for somemanagement units of a proposed dredging area,but not others, Tier IV evaluations should belimited to those management units in question.


Because there are no hard-and-fast rules in TierIV, it is imperative that the testing and evaluationbe coordinated with the DNREC. When usingtesting procedures which have no establishedinterpretive guidance, case-specific evaluativecriteria must be developed in advance.

Testing and Evaluation Procedures

The tools that are used in Tier IV to evaluatedredged material contaminant impacts mayinclude toxicity and bioaccumulation tests whichdiffer from the Tier III tests in both the level ofintensity and in cost. Examples of these differencesinclude: different end points, different test species,and varying exposure conditions to reflect case-specific field conditions.

The USEPA and USACE have developedmethodologies for the sub-lethal benthic toxicitytests with Chironomus tentans and Hyalella aztecaand sub-lethal water column toxicity tests withDaphnia magna, Ceriodaphnia dubi a, andPimephales promelas. These tests are developedfor measurement of growth as a sublethal response,and the procedures are provided in Appendix Gof the Great Lakes Dredged Material Testing andEvaluation Manual. Since the interpretationguidance for these tests has not been completedand accepted by the USEPA and USACE, the useof these sub-lethal toxicity tests remains an optionunder Tier IV.

The Inland Testing Manual (USEPA/USACE1998) lists a number of organisms for whichtoxicity and bioaccumulation tests have beendeveloped. Although few of these tests weredeveloped or used for regulatory decision making,this list can be used to identify potential speciesfor Tier IV testing.

Tier IV may also require tools to evaluate theexposure and impacts of dredged materialcontaminants in the field, away from the disposalsite, or on higher trophic levels. Examples of thesetools include: field biota collection, field exposures(caged organisms), contaminant transport/contaminant fate modeling, and human health/ecological risk analysis.

When planning a Tier IV evaluation, it isrecommended that the evaluator review theGuidelines and keep the following principles inmind throughout: a benthic evaluation is made ofcontaminant impacts relative to the disposal sitesediment, a water column evaluation mustconsider the effects of mixing, and a contaminantdetermination is directed at whether or not animpact will occur, and not why.

Determination

At the conclusion of Tier IV, there are two possibledeterminations which can be reached:


35

In addition to the predictions described above, theDNREC will require actual monitoring to beconducted during the excavation and dewateringto verify compliance with applicable standards.The amount and degree of depth necessary for theduring-dredging sampling will depend upon thelevel (Tier) of review for the pre-dredgeevaluation. Additionally, it will depend upon thedegree of certainty determined in the pre-dredgephase.

For more complex projects, sampling in the watercolumn surrounding the excavation will require,at a minimum, collection of data on totalsuspended solids concentrations, dissolvedoxygen, ammonia, and any contaminants ofconcern identified in the pre-dredge evaluation.Sampling for CDF effluent should follow thegeneral approach taken by the Corps of Engineers,Philadelphia District, in evaluating thePedricktown CDF (i.e. “Pedricktown ConfinedDisposal Facility Contaminant Loading and WaterQuality Analysis,” June 1999).

In addition to the maintenance and monitoring re-quirements discussed in the Operations chapter,there may be supplemental requests by theDNREC for post-dredge monitoring. This willdepend upon the size and location of the project,as well as the results and certainty involved in thepre-dredge and during-dredging analyses. Post-dredge monitoring should be coordinated with theDNREC since each project will have different

DURING-DREDGING ANALYSIS

POST-DREDGE MONITORING

36


a) The proposed dredged material dischargewill not cause unsuitable, adverse impacts.

b) The proposed dredged material dischargewill cause unsuitable, adverse impacts.

parameters and requirements.

CHAPTER 3. OPERATIONS

Purpose

The purpose of the Operations chapter is to addressthe project design criteria for dredging operations.It begins with general policies that apply to sitecharacteristics, engineering criteria, andmanagement protocols. The dredging methodssection begins with an overview of the types ofdredging in order to provide some backgroundinformation and to assist in selection of theappropriate equipment to satisfy engineering andenvironmental considerations. The disposalmethods section describes the most commonlyused disposal methods and the benefits anddrawbacks of each. Since confined uplanddisposal is the most commonly used method ofdisposal in Delaware, there is significantly moredetail in that section. Beach nourishment is alsohighlighted as a common practice in Delaware.Following the disposal information, a list of bestmanagement practices is presented for each phaseof a dredging/disposal project. These practicesare not mandates but rather may be encouragedbased upon specific facets of individual projects.

Minimization of Impacts

“Dredging shall be limited to the minimumdimensions necessary for the project and shallavoid sensitive areas such as wetlands, shellfishresources, and submerged aquatic vegetation.Delaware Surface Water Quality Standards mustnot be violated because of dredging operationsexcluding whatever temporary and minimalturbidity is unavoidable when using sounddredging practices” (DCP CMP Policies Specificto Marinas #7. Authority — State of DelawareMarina Regulations, Section II(E)(2)(b) and

II(E)(4)(a), revised February 22, 1993).

Assessment of Benthic Resources

“Benthic resources are protected because of theirimportance in the food chain and their value ascommercial and recreational food sources. [Ifrequired by a regulatory agency] the status of abenthic community must be assessed by theapplicant using frequency, diversity, andabundance measures approved by the DNREC. Asa part of this determination, the rapidbioassessment techniques of Luckenbach, Diazand Schaffner (1989) will be used by theDepartment to characterize benthic communities.The DNREC may modify this methodology asexperience is gained in applying these techniquesto Delaware waters. The DNREC may requiremonitoring of the benthos as a permit condition”(DCP CMP Policies Specific to Marinas #8.Authority – State of Delaware Marina Regulations,Section II(D)(6)(a)(b) & (c), revised February 22,1993).

Critical Habitat

“Construction of marinas shall not be permittedat sites that are recognized by the DNREC ascritical habitat. ‘Critical Habitat’ includes areasclassified by the DNREC and serving an essentialrole in the maintenance of sensitive species. Areasmay include unique aquatic or terrestrialecosystems that support rare endangered orthreatened plants and animals. Rare, endangeredor threatened species are defined by both state and/or federal listings” (DCP CMP Policies Specificto Marinas #9. Authority – State of DelawareMarina Regulations, Section II(D)(7), revisedFebruary 22, 1993 and DNREC RegulationsGoverning the Use of Subaqueous Lands dated

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GENERAL POLICIES REGARDING DREDGING OPERATIONS

September 2, 1992, Definition #10).

Water Quality

“The following concerns for protecting waterquality shall be specifically considered by theDepartment in evaluating applications fordredging projects:

1. All dredging is to be conducted in a mannerconsistent with sound conservation and waterpollution control practices. Spoil and fill areasare to be properly diked to contain the dredgedmaterial and prevent its entrance into anysurface water. Specific requirements for spoilsretention may be specified by the Departmentin the approval, permit or license.

2. All material excavated shall be transported,deposited, confined, and graded to drain withinthe disposal areas approved by the Department.Any material that is deposited elsewhere thanin approved areas shall be removed by theapplicant and deposited where directed at theapplicant’s expense, and any requiredmitigation [for the damage caused] shall alsobe at the applicant’s expense.

3. Materials excavated by hydraulic pipelinedredge shall be transported by pipeline directlyto the approved disposal area. All pipelinesshall be kept in good condition at all timesand any leaks or breaks shall be immediatelyrepaired. [Additionally, pipes and otherequipment should be removed as soon asfeasible after completion of a project or duringextended periods of idleness.]

4. Materials excavated and not deposited directlyinto an approved disposal area shall be placedin scows or other vessels and transported toeither an approved enclosed basin, dumpedand then re-handled by hydraulic dredge to anapproved disposal area, or to a mooring wherescows or other vessels shall be unloaded bypumping directly to an approved disposal area.

5. When scows or other vessels are unloadingwithout dumping, they shall have theircontents pumped directly into an approved

disposal area by means sufficient to precludeany loss of material into the body of water.

6. In approved disposal areas, the applicant mayconstruct any temporary structures or use anymeans necessary to control the dredge effluent,except borrowing from the outer slopes ofexisting embankments and/or hydraulicplacing of perimeter embankments. Forbermed disposal sites, a minimum freeboardof two (2) feet, measured vertically fromretained materials and water to the top of theadjacent confining embankment, shall bemaintained at all times.

7. The applicant shall not obstruct drainage ortidal flushing on existent wetlands or[adjacent] upland areas. The applicant shallleave free, clear, and unobstructed outfalls ofsewers, drainage ditches, and other similarstructures affected by the disposal operations.The dredged materials shall be distributedwithin the disposal area in a reasonablyuniform manner to permit full drainagewithout ponding during and after filloperations.

8. The dredging operation must be suspended ifwater quality conditions deteriorate [as a resultof dredge operations] in the vicinity ofdredging or spoil disposal site. Minimumwater quality standards may be included as anelement of the permit and shall be monitoredby the applicant. Violation of these conditionsshall be cause for immediate suspension ofactivity and notification of the Department.Dredging shall not be resumed until waterquality conditions have improved and theDepartment has authorized resumption”(Regulations Governing the Use ofSubaqueous Lands, 3.05 (C)).

Prohibited Activities

“The following types of dredging projects areprohibited.

1. Dredging of biologically productive areas,such as nursery areas, shellfish beds, and

Chapter 3. Operations

38

submerged aquatic vegetation, if suchdredging will have a significant or lastingimpact on the biological productivity of thearea [i.e. if biomass or biodiversity will bereduced significantly].

2. Dredging of new dead-end lagoons, newbasins and new channels, which have a lengthto width ratio greater than 3:1 [since long.narrow channels allow less mixing andaeration] and for which the applicant cannotprove, by clear and convincing evidence, thatsuch dredging would not violate State SurfaceWater Quality Standards [either during thedredging process or as a result of the newlycreated hydrography of the area]. Thissubsection shall not apply to marina projectsgoverned by the Marina Regulations.

3. Dredging channels, lagoons, or canals deeperthan the existing controlling depth of theconnecting or controlling waterway, unlessotherwise approved under Subsection3.03B(8) of these Regulations [which reads:“Slips, lagoons, basins, and access channelsshould be no deeper than the parent waterbody(i.e. no sill), and the depth should slope upwardtoward the landward extent from the parentwaterbody. Exception may be allowed onlyby individual review of the potentialenvironmental impacts and approval grantedby the Secretary of the Department”].

4. Dredging channels, cleaning marinas, of othersubaqueous areas by using propeller washfrom boats” (Regulations Governing the Useof Subaqueous Lands, 3.04(D)).

Fee Schedule

“No person shall remove any material from publicsubaqueous lands without Department approvaland receipt by the Department of full payment ofthe fee for the amount of material estimated to beremoved. The Department reserves the right todetermine the amount of material to be removedin dredging and/or filling projects” (RegulationsGoverning the Use of Subaqueous Lands,3.05(E)).

Restrictions

No permit will be issued to:

A. Dredge any channel through the wetlandsdeeper than the existing depth or the controlledchannel depth specified by the Corps ofEngineers at the point of connection to theadjacent navigable waterway to which thedredge channel is directly connected. TheSecretary in furtherance of the purposes of theAct may specify a lesser depth.

B. Dredge any channel through the wetlands thathas only one outlet to navigable water throughwhich the normal daily tide ebbs and flowsunless the channel is equipped, by aerators orother means, to maintain the Water QualityStandards for Streams that are issued . . . bythe Department.

C. Dredge channels through the wetlands withsides more nearly vertical than a slope thatrises one foot vertically for each three feet ofhorizontal distance except where conditionsof soil composition prevent slope stabilization,so that bulkheading must be used.

D. Utilize wetlands for any activity unless it:(1) Requires water access or water for the

central purpose of the activity; and(2) Has no alternative on adjoining non-

wetland property of the owner.E. Building bulkheads on wetlands higher in

elevation than the surface of the natural land.Navigational aids that do not prevent the ebband flow of the tide may be higher” (WetlandsRegulations, 2.01).1

1 Applicants should refer to the updated versionof the Wetlands Regulations, which were notavailable at the time of this printing, to familiarizethemselves with the most recent informationregarding bulkheading in wetlands.


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Sediment removal is accomplished generally bytwo mechanisms: hydraulic and mechanicaldredging.

Hydraulic dredges are generally used to removeloosely compacted materials. Cutterhead suction,dustpans, hoppers, plain suction, and sidecastersare types of hydraulic dredges where the dredgedmaterial is transported in a liquid slurry form.They are usually barge mounted and carry dieselor electric-powered centrifugal pumps withdischarge pipes ranging from 6 to 48 inches indiameter. The pump produces a vacuum on itsintake side, and hydrostatic pressure forces waterand sediments through the suction pipe to the mainpump. The slurry is then pumped through apipeline to a disposal/discharge area. Hopperdredges are generally self-propelled ships, whichare also included in the hydraulic category eventhough they operate independent of a pipeline. Thematerial is simply pumped into a self-contained

hopper on the dredge. The hopper is opened atthe disposal site to discharge the material or, ifequipped with pump-out capability, the hopper canhook up to a monobuoy and pump the materialthrough an anchored pipeline to the disposal/discharge area.

Mechanical dredges remove loose or hard,compacted materials by clamshell, dipper, orladder dredges, either for maintenance or new-work projects. These dredges remove bottomsediment through the direct application ofmechanical force to dislodge and excavate thematerial at almost in-situ densities. Backhoe,bucket (such as clamshell, orange-peel, anddragline), bucket ladder, bucket wheel, and dipperdredges are types of mechanical dredges.Sediments excavated with a mechanical dredgeare generally placed into a barge or scow fortransportation to the disposal site (EPA, USACE,Evaluating Environmental Effects of DredgedMaterial Management Alternatives – A TechnicalFramework, November 1992).


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Table 3.1. Summary of Dredge Operating Characteristics. a

Dredge Type Percent Solids in Turbidity Vessel Dredging Depths (ft) Slurry by Weight b Caused Draft (ft) Minimum Maximum

Mechanical Dipper In situ High d 0e 50 Bucket In situ Highc d 0e 100f

Hydraulic (non-hopper) Dustpan 10-20% Avg. 5-14 5-14 50-60g

Cutterhead 10-20% Avg. 3-14 3-14 12-65g

Hydraulic Hopper Hopper 10-20% Avg. 12-31 10-28 80Other Sidecasting 10-20% High 5-9 6 25 Special Purpose 10-20% Avg. 5-8 8 20

a Prepared by USACE – Waterways Experiment Stationb Percent solids could theoretically be 0, but these are normal working ranges.c Low, if watertight bucket is used.d Depends on floating structure; if barge-mounted, approximately 5 to 6 ft. draft.e Zero if used alongside of waterway, otherwise, draft of vessel will determine.f Demonstrated depth, theoretically could be used much deeper.g With submerged dredge pumps, dredging depths have been increased to 100 ft. or more.

(from USACE, EM 1110-2-5025, 1983)

DREDGING METHODS AND EQUIPMENT

The State of Delaware owns two hydraulicdredges, which are used by the DNREC, Divisionof Soil and Water Conservation to carry out itsmission under 7 Delaware Code 3905. Under thisstatute, the Department shall “[f]ormulate policiesand general programs to be carried out by theDepartment and by soil and water conservationdistricts for the prevention of erosion, floodwaterand sediment damages and for the conservation,protection, development and utilization of theState’s soil and water resources, including theimpoundment and disposal of water, and removalof sediment from waterways, lakes, ponds, andother bodies of water.” More information on thestate dredge program can be found in theEconomics Section of the Administration chapter.

The specifications on the state dredges are asfollows:

“Blue Hen”

Type: 10-inch hydraulic, pipeline cutterheadModel/Manufacturer: 370 Dragon Dredge, EllicottMachine CompanyMinimum/Maximum Swing: 20’ - 60’Minimum/Maximum Dredging Depth: 3.5’ – 20’Maximum Pumping Distance without BoosterPump: 5,000 feet (silt), 4,000 feet (sand) (Boosterpump will add approximately 2,500 – 3,000 feet ofdistance)

“Diamond State”

Type: 14-inch hydraulic, pipeline cutterheadModel/Manufacturer: 970S Dragon Dredge,Ellicott Machine CompanyMinimum/Maximum Swing: 45’ – 100’Minimum/Maximum Dredging Depth: 4’ – 26’Maximum Pumping Distance without BoosterPump: 4,500 feet (silt), 4.000 feet (sand)(Booster pump will add approximately 2,000 feetof distance)

Table 3.1 outlines some of the engineering featuresof various types of mechanical and hydraulicdredges and is intended to general reference only.

Alternatives for the management of dredgedmaterial must be carefully evaluated from thestandpoint of environmental acceptability,technical feasibility and economics. Threemanagement alternatives are discussed for dredgedmaterial: open-water disposal, confined disposal,and beneficial use. Open-water disposal is theplacement of dredged material in rivers, lakes,estuaries, or oceans via pipeline or release fromhopper dredges or barges. Confined disposal is theplacement of dredged material within dikednearshore or upland confined disposal facilities(CDFs) via pipeline or other means. Beneficialuse involves the placement or use of dredgedmaterial for some productive purpose (e.g. beachnourishment or stabilization projects).

Potential environmental impacts resulting fromdredged material disposal may be physical,chemical, or biological in nature. Because manywaterways are located in industrial and urbanareas, sediments often contain contaminants fromthese sources. Unless properly managed, dredgingand disposal of contaminated sediment canadversely affect water quality and aquatic orterrestrial organisms. Sound planning, design, andmanagement of projects are essential if dredgedmaterial disposal is to be accomplished withappropriate environmental protection and in anefficient manner.

The primary factors determining the mostappropriate form of disposal are sedimentcharacteristics and contaminant profile of thematerial. For example, some clean material issuitable for beneficial use projects includinghabitat creation or wetland restoration, whereascontaminated material must be disposed of morecarefully due to presence of toxicants. (See Figure3.1. for Dredge Material Management DecisionSupport Tree)

Most dredged material in Delaware can bemanaged in upland confined disposal facilities


41

DISPOSAL METHODS

(CDFs) which de-water into adjacent waterways.However, at some sites there are concerns aboutleachate impacts on groundwater and water qualityviolations in nearby surface waters. Finally, thereis a persistent problem of finding available andappropriate tracts of land to ensure adequatedisposal capacity for future dredging needs.

Each method of material disposal has variousbenefits and drawbacks that must be taken intoconsideration along with the unique features ofindividual projects or regions. This sectionprovides a general overview of site characteristicsand design standards while the EnvironmentalEvaluation chapter outlines the testing criterianecessary for each option.

Open Water Disposal

Open-water disposal is the placement of dredgedmaterial in rivers, lakes, estuaries, or oceans viapipeline or release from hopper dredges or barges.Such disposal may also involve appropriatemanagement actions or controls such as capping.Physical behavior and the resulting environmentalimpacts are dependant on the type of dredging anddisposal operation used, the nature of the material(physical characteristics), and the hydrodynamicsof the disposal site.

To evaluate open-water disposal a detailedassessment of the method including testingprocedures, management options and controlmeasures must be performed. Knowledge of sitecharacteristics is necessary for assessments ofpotential physical impacts and contaminantimpacts. Information on site characteristics neededfor assessments may include the following:

• Currents and wave climate;• Water depth and bathymetry;• Potential changes in circulation patterns or

erosion patterns related to refraction of wavesaround disposal mound;

• Bottom sediment physical characteristicsincluding sediment grain-size differences;

• Sediment deposition versus erosion;

• Salinity and temperature distributions;• Normal levels and fluctuations of

background turbidity;• Chemical and biological characterization of

the site and environs (e.g. relativeabundance of various habitat types in thevicinity, presence of submerged aquaticvegetation, and presence of unique, rare orendangered, or isolated populations);

• Potential for recolonization of the site;• Previous disposal operations;• Availability of suitable equipment for the

disposal site;• Ability to monitor the disposal site

adequately for management decisions;• Technical capability to implement

management options should they appeardesirable;

• Ability to control placement of the material;• Volumetric capacity of the site;• Other site uses and potential conflicts with

other activities (e.g., sport or commercialfisheries, shipping lanes, and military uses);

• Established site management or monitoringrequirements;

• Public and regulatory acceptability to use ofthe site (USEPA/USACE, 1992).

In Delaware, open water disposal is legal, but it isstrongly discouraged due to the turbidity andpotential water quality impacts. Projects usingopen water disposal will be carefully scrutinizedto ensure environmental protection, as will projectswith material disposal into the surf zone. In thesesituations the applicant must justify the choice ofdisposal with clear and convincing evidence thatthe disposal method will neither violate StateWater Quality Standards or cause lastingenvironmental damage.

Economic Loading or “Barge Overflow”

“Economic loading” is the term used to describethe practice where dredge hoppers and scows arefilled past the point of overflow to increase theload of solids. There is little debate that the loadcan be increased by overflow if the material


42

Figure 3.1. Dredge Material ManagementDecision Support Tree

Initially "Approved" Dredging Project

Assumes the project:! passed all initial cost-benefit

analysis thresholds! has an identified and permissible

purpose! passed Tier I environmental

screening

MaterialCharacterization

Methodology used may be specificto a project's type, location, andpurpose.

Contaminated? YesNo

Environmentaland/or Economic

Cost-Benefit Analysis

Volume,Grain Size

Decontaminatebased on

intended use

Do NotDredge

ConfinedDisposalFacility

TraditionalDisposalMethod

AlternativeUse

DecontaminateLater?

Yes

No

! CDF! Overboard

! Land fill cover! Construction fill! Soil additive! Habitat restoration! Beach nourishment! Upland creation! Erosion control! Material transfer


43

dredged is coarse grained or forms clay balls, ascommonly occurs with new-work dredging. Forthe fine-grained maintenance material, significantdisagreement exists as to whether a load gain canbe achieved by overflow. Environmentalconsiderations of overflow may be related toaesthetics, potential effects of water columnturbidity, potential effects of deposition of solids,or potential effects of sediment-associatedcontaminants. Applicants wishing to useeconomic loading techniques must consult withDNREC regarding location, sediment type, andnecessary testing and restrictions in order toevaluate the appropriateness of economic loadingfor the particular project. Due to uncertaintiesregarding the impacts from this practice, economicloading proposals will receive very carefulconsideration and a high threshold for review.

Confined Disposal

Confined disposal is placement of dredgedmaterial within diked nearshore or upland confineddisposal facilities (CDFs) via pipeline or othermeans. CDFs may be constructed as upland sites,nearshore sites with one or more sides in the water(often called intertidal sites), or as islandcontainment areas. The two objectives inherent indesign and operation of CDFs are to provideadequate storage capacity to meet dredgingrequirements and to maximize efficiency inretaining solids. However, if contaminants arepresent, control of contaminant releases must alsobe an objective.

Hydraulic dredging adds several volumes of waterfor each volume of sediments removed, and thisexcess water is normally discharged as effluentfrom the CDF during filling operation. When thedredged material is initially deposited in the CDF,it may occupy several times its original volume.The settling process is a function of time, but thesediment will eventually consolidate to its in-situvolume, or less if desiccation occurs. Adequatevolume must be provided during the dredgingoperation to contain the total volume of sedimentto be dredged (including transient water),

accounting for any volume changes duringplacement (USACE/USEPA, 1992).

To evaluate confined disposal a detailedassessment of the method including testingprocedures, management options and controlmeasures must be performed. Knowledge of sitecharacteristics is necessary for assessments ofpotential physical, biological, and contaminantimpacts.

Information on site characteristics needed forassessments may include the following:

• Available area and volumetric storagecapacity to contain the material for therequired life of the site;

• Real estate considerations;• Site configuration and access;• Proximity to sensitive ecological

environments;• Topography to include potential changes in

elevation, runoff patterns and adjacentdrainage;

• Ability of the dredged material to dry andoxidize;

• Groundwater levels, flow direction, andpotential impact of groundwater dischargeand recharge;

• Meteorology and climate;• Foundation soil properties and stratigraphy;• Potential groundwater receptors;• Potential alteration of the existing habitat

type;• Potential for effluent, leachate, and surface

runoff impacting adjacent ground andsurface water resources;

• Potential for direct uptake and movement ofcontaminants into food webs;

• Potential for volatilization of contaminants;• Potential for dust, noise, or odor problems;• Potential accessibility of the site to the

public;• Potential for creation of acid sulfate soils

(discussed below under MaterialCharacteristics);

• Contamination history of proposed site

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(USEPA/USACE, 1992).

Design, Operations and Management (newand existing) of Confined Disposal Facilities

When material is placed in a confined disposalfacility (CDF), it must be demonstrated that theplacement of the dredged material will not havesignificant adverse impacts to terrestrial or aquaticecosystems or pose risks to public health. In orderto minimize potential risks, the following mustbe considered: Location of the Facility and Site-specific Conditions; Material Characteristics;Design and Construction of Facility; Operationof the Facility; and Closure and use of the Facility.

• Location of the Facility and Site-specificConditions

The location of a proposed confined disposalfacility must be analyzed with considerationof the flow returning to surface andgroundwater systems. The siting is subject toreview under the Coastal Zone ManagementAct, Wetlands Act, local/county zoning board,and the Corps of Engineers through theirpermitting authority for dredging projects.

• Material Characteristics

The main concerns regarding confineddisposal of dredged material is the potentialfor surface or ground water contamination.Testing of materials for confined disposal andevaluations of the risks of contamination arediscussed in the Environmental Evaluationchapter.

One concern that is becoming increasinglywell understood is that of acid sulfate soils. Ifsulfidic soils (those containing oxidizablesulfur compounds) are exposed to oxidizingconditions such as atmospheric or dissolvedoxygen, the sulfur compounds oxidize andproduce acid. This can result in the soil pHdropping to about 4.0. Acidity restricts thegrowth of plants since it generates high

amounts of aluminum and iron, which are toxicto plants.

If acid sulfate soils are potentially present,these soils must be reclaimed in order toprevent environmental damage. Whileintroducing the common reed Phragmitesaustralis is one option to accelerate thereclamation process, this reed is considered anuisance in Delaware, and thus this practiceis not recommended. Another method thatmay be more promising is the application oflime on the soils. More information regardingacid sulfate soils can be found in the materialslisted in the references section by Dr. DelvinFanning.

• Design and Construction of the Facility

Design of the CDF site is similar to that forany earthen berm or dike. It must be capableof enduring under the forces of the dredgedmaterial placed inside as well as the hydraulicforces from the adjoining surface water,underlying ground water, stormwaterdischarges, and dewatering effluent. Thecontainment structure must be able towithstand the effects of erosion, settlement,provide a stable platform for the operation ofequipment, and allow for the potential verticalexpansion of the containment structure. Referto the “General Policies Regarding DredgingOperations” section for additional parametersguiding site design and construction.

In addition, an Erosion and Sediment Controlplan is required from the Division of Soil &Water Conservation for any upland soildisturbance of 5000 square feet or more.Several of the principles regarding erosion andsediment control are included for generalreference:

− An approved erosion and sediment controlplan must be followed. Any modificationsto the plan must be approved as revisionsto the approved plan.


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− Any site or portion thereof on which aland-disturbing activity is completed orstopped for a period of fourteen days mustbe stabilized either permanently ortemporarily following the specificationsand standards in theErosion and SedimentControl Handbook.

− Unless an exception is approved, not morethan [20 acres] may be cleared at any onetime in order to minimize areas of exposedground cover and reduce erosion rates.

− A land-disturbing activity shall not causeincreased sedimentation or acceleratederosion off-site. Off-site meansneighboring properties, drainageways,public facilities, public rights-of-ways orstreets, and water courses includingstreams, lakes, wetlands, etc.

More specific criteria for vegetation and bermstabilization can be found in the DelawareErosion and Sediment Control Handbook forDevelopment.

DNREC Sediment & Stormwater Regulationsdo not differentiate between different types ofland disturbing activities. Therefore, CDFswould require the same types of controls asother activities. The Delaware Erosion andSediment Control Handbook for Developmentcontains practices which should be adequatefor perimeter control and stabilization ofCDFs. There is one function of CDFs,however, which is unique. DNREC’s Erosionand Sediment Control practices are intendedto control periodic rainfall events up to about1" of runoff. Since CDFs are operated on amore continuous basis, dewatering operationsusing standard E&S practices would not beappropriate. The applicant must consult withthe Division of Soil & Water Conservation todetermine applicable construction andoperating procedures.

A permit regulating the discharge of effluentfrom the CDF is likely. Additional NationalPollution Discharge Elimination System

(NPDES) Storm Water Regulations apply,since a NPDES certification is required forland disturbing activities. The “RegulationsGoverning Storm Water DischargesAssociated with Industrial Activity, Part 2 –Special Conditions for Storm WaterAssociated with Land Disturbing Activities”(1998) states that “Land disturbing activitiesshall not commence and coverage under thisPart shall not apply until the Sediment andStormwater Management Plan for a site hasbeen approved, stamped, signed and dated . ..”. Applicants should consult DNREC,Division of Water Resources for specificrequirements.

The Department will use the technicalstandards of the following documents as thebasis for its engineering review of the designand construction of the proposed CDFs:

Confined Disposal of Dredged Material –Engineering Manual (EM 1110-2-5027), U.S.Army Corps of Engineers, 1987.

Confined Disposal Guidance for SmallHydraulic Maintenance Dredging Projects –Design Procedures, Environmental Effects ofDredging Technical Note EEDP-02-8, U.S.Army Corps of Engineers, 1988.

• Operation of the Facility

The operation of the CDF must be monitoredto ensure the stability and integrity of thecontainment structure and to preventuncontrolled release of material, ponded water,and associated contaminants. Oversight mustalso ensure that the site is filled at a rate thatallows efficient functioning of the facility andmoderates the discharge of dewateringeffluent. Potential impacts to human andterrestrial ecosystems must also be considered.

An annual report must be submitted by theCDF owner/operator to the Department of

46


Natural Resources and Environmental Control.The report will summarize the past year’sactivities and the projected activities for thenext five (5) years. The report shall documentthe following information:

1. Conditions of containment berms,dewatering and stormwater dischargeweirs, and other engineering structurescritical to the operation of the CDF. Anychanges to the CDF must be first approvedby the Department and revised “as built”plans documenting any significant changessubmitted.2. Summary of disposal operations at theCDF, including a listing of all dredgingprojects and their volumes.3. Summary of maintenance andmanagement activities conducted at theCDF, including regrading, ditching, crustmanagement, and interim closureprocedures, if required.4. Summary of any dredged materialremoved from the CDF and its final use/destination.5. An analysis of available disposalcapacity in the CDF. This will becompared with the projected disposalactivities for the next five (5) years and arunning total of available capacity for thenext five years estimated.6. Summary of surface and ground waterdischarge monitoring programs for allrequired parameters.7. Any additional monitoring orcertifications required.

In addition, the following sections from theRegulations Governing the Use of SubaqueousLands (repeated from “General Policies”section above) are included here as theyaddress disposal site design:

− In approved disposal areas, theapplicant may construct any temporarystructures or use any means necessaryto control the dredge effluent, except

47


borrowing from the outer slopes ofexisting embankments and/orhydraulic placing of perimeterembankments. For bermed disposalsites, a minimum freeboard of two (2)feet, measured vertically from retainedmaterials and water to the top of theadjacent confining embankment, shallbe maintained at all times.

− The applicant shall not obstructdrainage or tidal flushing on existentwetlands or upland areas adjacentthereto. The applicant shall leave free,clear, and unobstructed outfalls ofsewers, drainage ditches, and othersimilar structures affected by thedisposal operations. The dredgedmaterials shall be distributed within thedisposal area in a reasonably uniformmanner to permit full drainage withoutponding during and after fill operations(Section 3.05(c), 9-10).

• Closure and use of the Facility

Interim Closure

Any site or portion thereof on which a land-disturbing activity is completed or stopped fora period of fourteen days must be stabilizedeither permanently or temporarily followingthe specifications and standards in the Erosionand Sediment Control Handbook.

Concerns at interim closure includeminimizing potential for human or plant/animal exposure to contaminated dredgedmaterial. For that reason, testing of theexposed (surface) dredged material within thesite may be necessary.

Measures must be put in place to control dustand to limit access to the site for public safetyreasons, as the material will not have solidifiedto hard ground. It may also be necessary tocap the exposed material with clean fill or tolime in order to encourage plant growth.

During periods of non-use, requirements of allpermits including NPDES, State WaterQuality Certification, and Sediment andErosion Control plan must be satisfied. If theperiod of non-use is to last longer than fiveyears, the site operator must implement theprocedures for final closure.

Final Closure

The goal of final CDF closure is to ensurecontainment of potentially contaminateddredged material. The owner of record of theproperty on which the upland CDF isconstructed is ultimately responsible for thefinal closure of the facility and any requiredpost-closure monitoring.

Formal plans must be submitted to addressfinal closure, post-closure maintenance andmonitoring, and site development or use forall upland CDFs. The Final Closure Plan mustpropose all engineering controls designed tocontain the contaminated dredged material andprevent direct contact with, and off-sitetransportation of, contaminants of concern.Another major component of the Plan willrelate to cap design. In general, a minimumthickness of two feet of cover, consisting of18 inches of clean fill overlain by 6 inches oftopsoil, with a complete vegetative cover, willbe required.

Because CDF closure designs varysignificantly, it is important that the CDFowner or operator consult with DNREC,Division of Soil & Water, regarding theclosure plans for a particular site. This willenable the Final Closure Plan to reflect theunique situation of location, material content,and future purpose of the site.

Alternative Disposal Methods and Beneficial Use

Beneficial use of dredged materials includes awide variety of options for utilizing dredged

material for some productive purpose. Dredgedmaterial is potentially a manageable soil resourcewith beneficial uses that could be incorporated intoproject plans and goals. Additionally, by usingthe dredged material for some constructivepurpose, it keeps clean fill from being placed intoupland disposal facilities where it may mix withcontaminated material, thereby rendering itunusable. Use of valuable coastal land forconstructing new confined disposal facilities canalso be reduced.

At the outset, it is important to note that there issome concern regarding the term “beneficial,” assome projects may not be perceived to yield apositive environmental benefit. For the purposeof this document, the term “beneficial” will beused, since it is the standard term for describingany uses where material is considered a resource.

Below are the ten broad categories of beneficialuses that have been identified by the USEPA andUSACE, based on functional use of the dredgedmaterial or site area. These are presented here togive a broad idea of possible uses of material;however, not all of these categories may beappropriate or approved for specific projects inDelaware.

1. Habitat restoration/enhancement (wetland,upland, island, and aquatic sites includinguse by waterfowl and other birds);

2. Beach nourishment;3. Aquaculture;4. Parks and recreation ;5. Agriculture, forestry, and horticulture;6. Strip mine reclamation and landfill cover

for solid waste management;7. Shoreline stabilization and erosion control

(fills, artificial reefs, submerged berms,etc.;

8. Construction and industrial use (includingport development, airports, urban, andresidential);

9. Material transfer (fill, dikes, parking lots,and roads);

10. Multiple purpose (USEPA/USACE,1992).

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habitats (shellfish beds, SAV, EssentialFishHabitat) should be avoided – they are alreadyfunctional habitat.

Recommended factors for evaluation wouldinclude:

• Quantity of clean material;• Sediment quality (physical and chemical

characteristics);• Suitability of material to proposed use;• Habitat assessment (what is gained and/

or lost);• Evaluation of proposed use with traditional

disposal methods;• Past historical success (or failure and

reasons);• Has monitoring been conducted? Is the

new habitat functional?;• Is there an acceptable candidate site?;

Does it already have a valuablehabitat?;

Will it support the intended use (birdrookery, etc)?;

Is design/engineering/monitoringadequate? feasible?;

Is cost of construction andmaintenance/management/monitoringjustified?;

• Is the project truly beneficial or subject tofailure? Or is the risk of failureacceptable?;

• Will the project be sited in a place whereit will persist? (i.e. wetland on east side ofestuary) or where erosion will remove it(west side)?

Alternative/beneficial use should be considered ifat all possible, although it shall not be used as thesole justification for the project. Applications withthese uses should be subject to the same reviewprocedures and requirements as the parent project.It may also be necessary to foresee and deal withadverse public opinion on some projects.Additionally, the project sponsor must takeresponsibility for the management and monitoringof the site and be prepared to make necessary

fine coarse

Habitat Restoration x xBeach Nourishment xAquaculture x xParks & Rec. (upland creation) x xAg, forestry, horticulture xStrip mines & landfills x xErosion and shoreline x xConstruction & urban x xMaterial transfer x xMultiple purpose x x

Table 3.2. Material Uses by Grain Size

One factor that influences disposal methods is thegrain size of the material. Fine material is definedby the Wentworth Sediment Size ClassificationSystem as less than 0.0625 mm in diameter, whilecoarse material is greater than 0.25 mm. Thefollowing table indicates the classification ofsediment types that would be most suitable forparticular beneficial use projects.

When considering habitat re-creation as abeneficial use for dredged material, it is necessaryto weigh what will be lost against the potential“gain.” In some cases, the habitat already existingin an area may be fairly valuable, especially whencompared with the risk of failure that is taken withany habitat restoration project. One examplewould be a shallow water habitat, which can bepopulated with shellfish and provides feedinggrounds for birds, being filled to create a wetland.For example, the “cost” of smothering benthicorganisms in a shallow water habitat must beweighed against the “benefit” of a wetland habitatfor a particular area.

Developing appropriate sites and projects forbeneficial use of material is an importantconsideration. Areas that are already high-value

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pro· Avoids the need for new disposal capacity· Yields a marketable commodity· Usually good for public relations· Reclaims brownfields· Creates/restores wildlife habitat· Meets two needs – 1) disposal, and 2) habitat

creation, beach nourishment, etc.

con· Usually more expensive than traditional

disposal· Potential for impacts to existing habitat· Results in increased handling with

management requirements· Possibility that the project will not meet

expectations or will fail

Leave Alone (don’t dredge)

pro· No cost· No environmental disturbance or potential for

degradation of wateway

con· Navigational or other need not met

Confined Disposal

pro· Can handle contaminated sediments safely· Can offer long-term disposal· Normally cheaper per unit in existing sites· Provides material for re-use

con· Limited life span· New sites expensive· Environmental impacts are possible

modifications in order to maintain its uses andfunctions.

Beach Nourishment

Placing sand from a navigational dredging projectonto an eroding beach can provide an opportunityfor beneficial use of dredged material. However,in other cases, sand is dredged for the expressedpurpose of beachfill, and the following sectionaddresses the unique features of beachnourishment projects. Dredging offshore sand andplacing it on Atlantic Coast and Delaware Baybeaches has provided shoreline stabilization,preserved recreational opportunities, and protectedcoastal properties. It is the policy of the State toprotect its beach resources, and several economicstudies have indicated that the policy is cost-effective.

In some cases, material from Inland Baysnavigation projects can provide suitable materialfor Atlantic Coast nourishment. However, therehave also been instances of grain size or materialincompatibilities (i.e. silt-clay or mud). Carefultesting for grain size, and more testing cores perlocation, should determine whether or not materialis suitable for placement on beaches. The sedimentcomposition and grain size should be very similarto that on the recipient beach, and any variationshould be statistically valid. An applicant willwork with DNREC to develop a project designthat optimizes beach nourishment objectives.Material slated for beach nourishment, regardlessof whether it is a beneficial use of material from anavigational project or excavated expressly fornourishment, should have grain size characteristicsvery similar to the intended placement site.

Disposal Selection Summary

The grain size, contaminant profile, amount,location, etc. all influence the selection of adisposal alternative for dredged material. Thefollowing chart outlines the general arguments forand against certain disposal methods. This isintended for general reference in the early stages

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DISPOSAL ALTERNATIVES

of project planning as the alternative analysis isundertaken.

Beneficial Use

BEST MANAGEMENT PRACTICES (BMP’S) FOR

DREDGING OPERATIONS

any adverse impacts that may result from aparticular project. Authorized best managementpractices exist for a wide-range of activitiesincluding agriculture and construction projects ofall types. Numerous BMPs have also beenidentified that address specific concerns resultingfrom the operation of a dredge. The main concernsusually include suspended solids (including there-suspension of contaminated sediments) anddisruption of aquatic habitats and fish and wildlife.It is the goal of the Department to regulate projectsin such a way as to minimize the potential foradverse environmental impacts to occur.

A permit for any dredge operation may requirethat certain BMPs be used in order to minimizeadverse environmental impacts to the area. TheBMPs required for each permitted project will bedifferent based upon site conditions (sedimentcontamination, sediment type, and location), scopeof the project, type of dredge to be used and habitatconcerns.

The following is a list of common BestManagement Practices used in Delaware, brokendown by category. This list is not intended to bea comprehensive list of all BMPs in Delaware,thus additional practices not listed here may berequired or recommended for certain projects.

Practices that reduce suspended sediments atthe dredge site:

Silt Curtains

The use of silt curtains can minimize thedispersal of sediments from the upper watercolumn in the dredging area. It is also usefulfor protecting tidal creeks adjacent to thedredge site from excess sedimentation. ThisBMP is practical for use in areas where thewater current is less than 1 knot.

Hydraulic Dredging

Hydraulic dredging reduces the amount ofsuspended sediments generated at the dredging

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· Double-handling creates additional expense· Potential for changes in land use

Overboard Disposal

pro· Inexpensive and easy method· Creates future borrow sites

con· Cannot be used for contaminated material· Potential environmental impacts (DO,

resuspension, bioavailability, habitatdegradation)

· Requires double-handling if used for borrowmaterial

Transport of Dredged Material

Methods used to move dredged material includepipelines, barges or scows, and hopper dredges.Pipeline transport is the method most commonlyassociated with cutterhead, dustpan, and otherhydraulic dredges. Dredged material may bedirectly transported by hydraulic dredges throughpipelines for distances of up to several miles,depending on conditions. Barges and scows, usedin conjunction with mechanical dredges, have beenone of the most widely used methods oftransporting large quantities of dredged materialover long distances. Hopper dredges are capableof transporting the material for long distances in aself-contained hopper. Hopper dredges normallydischarge the material from the bottom of thevessel by opening the hopper doors; however,some hopper dredges are equipped to pump thematerial from the hopper much like a hydraulicpipeline dredge (USEPA/USACE, 1992).

Best Management Practices, commonly referredto as BMPs, are methods for carrying out a taskthat minimize the potential for, and magnitude of,

site. However, this method produces a dredgedmaterial slurry that has a high water percentageand thus it is preferable only when an approvedconfined disposal facility (CDF) is available forthe disposal of sediments.

Closed Clamshell Dredging

Dredging using a closed, watertight clamshellreduces the amount of suspended sedimentsgenerated at the dredging site. This BMP issuggested when the sediments to be dredgedare known to be contaminated at levelswarranting concern.

When using a clamshell dredge, the followingpractices should also be followed:

1. Maximize the size of the “bite” of theclamshell to reduce the overall amount of“bites” needed for completion of theproject;

2. Slowly withdraw the clamshell through thewater column to minimize spillage;

3. Do not rinse sediments off the sides andgunwales of the barge.

No-Barge-Overflow

No-barge-overflow can reduce the creation anddispersal of suspended sediments when finer-grained sediments are to be dredged. Once ahopper dredge is filled to capacity, dredgingis stopped immediately so that material doesnot overflow the sides of the hopper. It isespecially encouraged when those sedimentsare known to have contaminant levels thatwarrant concern.

Shunting

Shunting can reduce turbidity in the upperwater column. This method involves activelypumping free water in a barge to the bottomof the water column at the dredging site. Thedischarge end of the shunting system must

include a diffuser in order to minimize thepotential for additional disruption of benthicsediments. Additionally, the pumping rate andlocation of the discharge must not result in thedisruption of in-place sediments.

Dredging during the in-coming tide

In certain semi-enclosed water bodies,dredging on only the in-coming tide canprovide additional time for suspendedsediments to settle. This will minimize thedispersal of sediments out of the water body.

Practices that minimize impacts to aquatichabitat and dwellers:

Use of seasonal windows

Dredging operations are prohibited in specificareas during certain times of the year tominimize any potential impacts to anadromousor other migratory finfish, nesting shorebirds,etc.

The Delaware Basin Fish and WildlifeManagement Cooperative give guidance forseasonal restrictions for the mainstem of theDelaware River. Hydraulic pipeline andhydraulic hopper dredging is prohibited innon-Federal areas from the DelawareMemorial Bridge northward from April 15 –June 21. Bucket dredging is prohibited in allareas north of the Delaware Memorial Bridgefrom March 15 until May 31. Blasting/overboard disposal is prohibited in all areasnorth of the Delaware Memorial Bridge fromMarch 15 until November 30. Hydraulichopper dredging in all areas from DelawareBay to the Delaware Memorial Bridge requiresturtle monitoring, as per the National MarineFisheries Service Biological Opinion, Nov. 26,1996.

Applicants should consult the DNREC,Division of Fish and Wildlife to determineappropriate windows for their particular

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project location and season.

Practices for beach nourishment projects:

Use of large dredges or more booster pumps forbeach nourishment projects

The use of larger dredges or more boosterpumps for beach nourishment projects wouldpermit sediment collection further from theshoreline. This might allow nearshore shoalsto remain intact, although mobilization costsmust also be taken into consideration.

Selection of borrow areas

Borrow areas for beach nourishment projectsshould be located far enough offshore to ensurethat sand washing off the beach would not goback into the area. Borrow areas should alsobe far enough offshore to preclude injury tobeach-goers. The average adequate distancealong Delaware Bay beaches is about 1,000feet. Along the Atlantic beaches the distanceoffshore would be dictated by the “depth ofclosure” which is approximately –25’MLW.

Inspect material being discharged

Visually inspect the material being dischargedalong the shoreline at all times during theproject. If unsuitable material (e.g. silt/mud)is observed, notify the dredge immediately forshutdown. Relocate the dredge within theapproved borrow area where suitable material(sand) is located and resume operations.

Adhere to special conditions

Adhere to any special conditions placed uponprojects via State and Federal permit approval.

Other practices:

Minimize volume of dredged materials

Plan, design, and implement projects to dredge

the minimum possible volume to attain thegoals set forth by the project proposal.

Employment of dredging inspectors

Dredging contractors may be required toemploy independent, on-board dredginginspectors certified by the U.S. Army Corpsof Engineers. These inspectors will observedredging and disposal operations to ensurecompliance with all permit conditions. Thefederal government requires such inspectorsfor all ocean disposal projects. Moreinformation regarding these requirements canbe found in the Delaware Bay Fish andWildlife Cooperative guidance pertaining todredging windows.

Dredged material pumping systems

The use of a number of pumping systemsincluding positive displacement pumps andvortex type pumps, can provide for moreprecise dredging operations and minimize there-suspension of sediments at the dredging site.These systems can also reduce the volume ofthe de-watering discharge from a CDF,reducing the potential impacts to surface waterquality.

Positive displacement pumps move materialat in situ moisture levels, resulting in thegreatest percent solids transfer. These devicesare typically used for concrete and can achievepumping capacities in excess of 140 cubicyards per hour.

Use of vortex type pumps can result in reducedwater content of the dredged material. This,in combination with a directional controlsystem serves the same function as a closedclamshell or hydraulic cutterhead. However,the material removed has an increased solidscontent compared to typical hydraulic dredgesand is similar to a closed clamshell, but withfar less sediment disturbance and turbiditygeneration.

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Accretions – an increase of land along the shores of a body of water.

Ambient conditions – those physical, chemical, and biological conditions present in the surroundingarea of the project site

Anadromous fish – fish that migrate from oceanic to coastal waters, or from salt water to fresh water

Benthic – the bottom of a water body

Benthos – see benthic; the organisms living on the bottom of a water body

Best management practices (BMPs) – methods and measures employed to reduce the adverseenvironmental impacts resulting from a dredging or dredged material management/disposal activity

Bioaccumulation – the accumulation of contaminants in the tissues of organisms through any route,including respiration, ingestion, or direct contact with sediment or water; indicates the biologicalavailability of contaminants

Bioassay (test) – acute or sublethal/chronic toxicity or bioaccumulation tests using organismsrepresentative of the water column, benthic, and terrestrial environment(s) at the dredging or dredgedmaterial disposal site.

Clamshell dredge – a dredging bucket comprised of two hinged jaws; a boat or barge equipped withsuch a machine

Confined disposal facility - Confined disposal is placement of dredged material within diked nearshoreor upland confined disposal facilities (CDFs) via pipeline or other means. CDFs may be constructed asupland sites, nearshore sites with one or more sides in the water (often called intertidal sites), or asisland containment areas.

Containment area – any site used for the permanent disposal or temporary confinement of dredgedmaterial, and which may or may not have a permanent retaining structure, located in an open water orwetland area directly adjacent to an upland area

Dewatering – the practice of actively or passively removing water from dredged material, usuallyoccurring in a barge or upland confined disposal facility

Effluent – particular reference to the quality of water coming over a weir from a dredged materialupland confined disposal facility during and after a disposal operation

Elutriate (test) – involves mixing dredged material with dredging-site water and allowing the mixtureto settle, the potential release of dissolved chemical constituents from the dredged material is determinedby chemical analysis of the supernatant (elutriate) remaining after undisturbed settling

GLOSSARY

55

Freeboard – the distance between the waterline and the upper most full deck

Hopper dredge – self-propelled seagoing ships equipped with sediment containers (hoppers), dredgepumps, and other special equipment. Dredged material is raised by dredge pumps through drag arms incontact with the bay/ocean bottom and discharged into hoppers built in the vessel.

Hydraulic dredging – Hydraulic dredges are generally used to remove loosely compacted materials.Cutterhead suction, dustpans, hoppers, plain suction, and sidecasters are types of hydraulic dredgeswhere the dredged material is transported in a liquid slurry form.

Mechanical Dredge - Mechanical dredges remove loose or hard, compacted materials by clamshell,dipper, or ladder dredges, either for maintenance or new-work projects. These dredges remove bottomsediment through the direct application of mechanical force to dislodge and excavate the material atalmost in-situ densities. Backhoe, bucket (such as clamshell, orange-peel, and dragline), bucket ladder,bucket wheel, and dipper dredges are types of mechanical dredges.

Mitigation – the replacement or substitution of a habitat in repayment for habitat that has been degradedor destroyed

Mixing zone – an “allocated impact zone” where numeric water quality criteria can be exceeded aslong as acutely toxic conditions are prevented. A mixing zone is a limited area or volume where theinitial dilution of a discharge occurs (Versar, 1996).

Ocean disposal – the practice of dredged material disposal via oceangoing barge into a designateddisposal site in deep, open water, often miles from shore.

Open water disposal – the practice of dredged material disposal anywhere into open water, exclusiveof disposal into a subaqueous disposal pit or containment area

Permit – an authorization, license, or equivalent control document issued by the U.S. EnvironmentalProtection Agency, U.S. Army Corps of Engineers, or approved State agency to implement therequirements of an environmental regulation

Plankton – plant and animals that float or drift in fresh or salt water

Planktonic – see plankton; of or relating to the organisms of the plankton

Pollutants – any gaseous, chemical, or organic waste (natural or man-made) that contaminates air,soil, sediment, or water, and has the potential for harm to human health, to any aspect of human ornatural ecosystems, or to environmental aesthetics or vitatlity

Riparian landowner – the landowner of a bank of a natural course of water

Nekton – marine organisms that swim independently of currents

Nektonic – see nekton; of or relating to the organisms of the nekton

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Glossary

Sorbed – to take up and hold as by absorption of adsorption

Subaqueous – found or occurring underwater

Supernatant – the clear fluid floating on the surface over a sediment or precipitate

57

Glossary

REFERENCES

Briuer, Elke. (1998). Sediment quality guidelines: An approach to dredged material management Part1, Aquatic environments. Dredging Research. U.S. Army Engineer Waterways Experiment Station.Vicksburg, MS.

Brown, Naomi. (1998). Dredging Waterways to Ports. The Future of American Ports. ed: Gerard J.Mangone. University of Delaware, Graduate College of Marine Science. Newark, DE.

Christie, Donna. (1994). Coastal and Ocean Management Law in a Nutshell. St. Paul, MN: WestPublishing Co.

Comprehensive Water-Use Plan for Delaware’s Inland Bays. A report prepared for The Center for theInland Bays and the Environmental Protection Agency, Region III. Pub date believed to be late 1998/early 1999.

Confined Disposal of Dredged Material – Engineering Manual (EM 1110-2-5027), U.S. Army Corpsof Engineers, 1987.

Confined Disposal Guidance for Small Hydraulic Maintenance Dredging Projects – Design Procedures,Environmental Effects of Dredging Technical Note EEDP-02-8, U.S. Army Corps of Engineers, 1988.

Delaware Department of Natural Resources and Environmental Control, Division of Water Resources.Regulations Governing the Use of Subaqueous Lands. Amended September 2, 1992.

Delaware Department of Natural Resources and Environmental Control, Division of Soil and WaterConservation. Delaware Erosion and Sediment Control Handbook for Development.

Delaware Department of Natural Resources and Environmental Control, Division of Soil & WaterConservation, Delaware Coastal Management Program. (1999). Updated Delaware Coastal ManagementProgram. Dover Delaware.

Delaware Department of Natural Resources and Environmental Control, Division of Water Resources,Watershed Assessment Branch. (1999). Chemical Contamination in Finfish from the Chesapeake &Delaware Canal and Implications to Human Health Risk.

Delaware Inland Bays Comprehensive Conservation and Management Plan. (1995). USEPA andState of Delaware. Doc # 40-08/95/05/01.

DNREC Dredge Program. DNREC, Division of Soil & Water Conservation. Short handout.

Fanning, D.S., and S.N. Burch. Coastal Acid Sulfate Soils. Manuscript of paper accepted for publicationin second edition of Reclamation of Drastically Disturbed Lands. ASA publicaton edited by R.I.Barnhisel, R.G. Darmody, and W.L. Daniels. Contribution No. 9170 of the Maryland Agric. Exp. Sta.,Dep. of Natural Resource Sciences and Landscape Architecture, Univ. of Maryland, College Park,MD. 1/10/97 manuscript version “as resubmitted with corrections.”

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How Does Essential Fish Habitat Affect Coastal Zone Management and Why Should You Care?Coastlines. Urban Harbors Institute. University of Massachusetts, Boston. June 1999.

Inland Bays Dredging Study. (1986). BCM Eastern, Inc. (Plymouth Meeting, PA) in conjunction withRogers, Golden, and Halpern (Philadelphia, PA) for Delaware Department of Natural Resources andEnvironmental Control. BCM Project No. 00-0104-01.

Interagency Working Group on the Dredging Process, Maritime Administration (December 1994).The Dredging Process in the United States: An Action Plan for Improvement.Klemm, D.J., G.E. Morrisori, T.J. Norberg-King, W.H. Peltier, and M.A. Heber. (1994) Short-TermMethods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and EstuarineOrganisms. Environmental Monitoring Systems Laboratory – Cincinnati, Office of Research andDevelopment, U.S. Environmental Protection Agency. EPA/600/4-91/003

Maryland Coastal Bays CCMP. (June 1999). Recreation & Navigation section.

National Dredging Team. (1998). Local Planning Groups & Development of Dredged MaterialManagement Plans.June 1998.

PIANC – International Navigation Association (Brussels, Belgium). dredging: the facts. Pamphlet.printed in The Netherlands.

Parsons, George R., and Michael Powell. (1998). The Cost of Beach Retreat: A Hedonic Price Analysisof Delaware Beaches. Working Paper No. 98-14. University of Delaware, College of Business andEconomics, Department of Economics. Newark, DE.

Reine, K., and D. Clarke. (1998). Entrainment by hydraulic dredges – A review of potential impacts.Technical Note DOER-E1. U.S. Army Corps of Engineers, Research and Development Center.Vicksburg, MS.

Scotto, Susan L., Robert B. Biggs, Betsy Brown, Andrew T. Manus, and Jean M. Lyman. (1983).Decisions for Delaware: Sea Grant Looks at the Inland Bays. DEL-SG-01-83. College of MarineStudies, University of Delaware. Newark, DE.

Slade, David, C, R. Kerry Kehoe, and Jane K. Stahl. (1997). Putting the Public Trust Doctrine to Work.Prepared by Coastal States Organization, Inc.

Urban Harbors Institute. (1999). “America’s Green Ports: Environmental Management and Technologyat US Ports.” Preview Report.

U.S. Army Corps of Engineers. (1999). Dredging Operations and Environmental Research (DOER)Technical Notes. Case Studies: Characterization Tests to Determine Dredged Material Suitability forBeneficial Uses. DOER-C7.

U.S. Army Corps of Engineers. (1990). Engineering Regulations. ER 1105-2-100. Section VII - NEDBenefit Evaluation Procedures: Transportation Deep-Draft Navigation.

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References

U.S. Army Corps of Engineers. (1998). Long-Term Effects of Dredging Operations Program (LEDO).Dredging Research Technical Note EEDP-04-29, Use of Sediment Quality Guidelines (SQGs) in DredgedMaterials Management.

U.S. Army Corps of Engineers. (1998). Long-Term Effects of Dredging Operations Program (LEDO).Dredging Research Technical Note EEDP-02-25, Predicting Surface Runoff Water Quality from UplandDisposal of Contaminated Dredged Material.

U.S. Army Corps of Engineers. (1983). Office of the Chief of Engineers. Dredging and Dredged MaterialDisposal. EM 1110-2-5025.

U.S. Army Corps of Engineers. (1985). Regulatory Program: Applicant Information. EP1145-2-1.

U.S. Army Corps of Engineers/U.S. Environmental Protection Agency. (1992). EvaluatingEnvironmental Effects of Dredged Material Management Alternatives – A Technical Framework.

U.S. Army Corps of Engineers. (1996). Waterways Experiment Station. Environmental Effects ofDredging Technical Notes: Proposed New Guidance for Interpreting the Consequences ofBioaccumulation from Dredged Material. EEDP-01-41.

U.S. Army Corps of Engineers. (1988). Waterways Experiment Station. Environmental Effects ofDredging Technical Notes: Corps of Engineers’ Procedures and Policies on Dredging and Dredgedmaterial Disposal (The Federal Standard). EEDP-04-8.U.S. Army Corps of Engineers. (1988). Environmental Effects of Dredging Technical Notes: APreliminary Evaluation of Contaminant Release at the Point of Dredging. EEDP-09-3.

U.S. Army Corps of Engineers. (1988). Waterways Experiment Station. Environmental Effects ofDredging Technical Notes: General Guidelines for Monitoring Effluent Quality From Confined DredgedMaterial Disposal Areas. EEDP-04-9.

U.S. Environmental Protection Agency/ U.S. Army Corps of Engineers. (1992). EvaluatingEnvironmental Effects of Dredged Material Management Alternatives – A Technical Framework.EPA842-B-92-008.

U.S. Environmental Protection Agency/U.S. Army Corps of Engineers. (1998). Inland Testing Manual.EPA 823-B-98-004

Versar. 2000. Assessment of Potential Contaminant Impacts for the Chesapeake and Delaware CanalDeepening Project. Prepared for U.S. Army Corps of Engineers, Philadelphia District by Versar, Inc.,Columbia, MD.

Versar. 1996. Mixing zone analysis for the Delaware River deepening project. Prepared for U.S.Army Corps of Engineers, Philadelphia District by Versar, Inc., Columbia, MD.

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References

ACRONYMS

B M P Best Management Practices

C C M P Comprehensive Conservation Management Plan

CDF Confined Disposal Facility for dredged material

CIB Center for the Inland Bays, DE

C O E U.S. Army Corps of Engineers

CORMIX Cornell Mixing Zone Expert System

C W A Clean Water Act

C Z M Coastal Zone Management (Act)

D A W M DNREC, Division of Air & Waste Management

DCP DNREC, DSWC, Delaware Coastal Programs

DNREC Delaware Department of Natural Resources and Environmental Control

D F W DNREC Division of Fish & Wildlife

DGS Delaware Geological Survey

DPR DNREC, Division of Parks & Recreation

DRBC Delaware River Basin Commission

D S W C DNREC, Division of Soil & Water Conservation

D W R DNREC, Division of Water Resources

EFH Essential Fish Habitat

EPA U.S. Environmental Protection Agency

GIS Geographic Information System

M A F M C Mid-Atlantic Fishery Management Council

NED National Economic Development (Plan)

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NMFS NOAA, National Marine Fisheries Service

NOS NOAA National Ocean Service

NO A A National Oceanic & Atmospheric Administration

R H A Rivers & Harbors Act

STORET Storage and Retrieval system database (EPA)

TBP Theoretical Bioaccumulation Potential

TSS Total Suspended Solids

U of D University of Delaware

USACE U.S. Army Corps of Engineers

USFWS U.S. Fish & Wildlife Service

UD-CMS University of Delaware, College of Marine Studies

USGS U.S. Geological Survey

W E S Army Corps Waterways Experiment Station (Vicksburg, MS)

W R D A Water Resources Development Act

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Acronyms

PROJECT PARTICIPANTS

The following list indicates those individuals who have participated in the process to develop Delaware’sStatewide Dredging Policy Framework. Those whose names are in bold are members of the CoreDredging Working Group and completed the majority of the work on this project.

Lawrence BaierOffice of Dredging & Sediment TechnologyNJ Dept. of Environmental Protection

Darrell BakerSummit North Marina

Richard BironPrivate Citizen

Lynn BroaddusNatural Heritage ProgramDNREC, Div. of Fish & Wildlife

Chris BrownDelaware Nature Society

Williams BurtonVERSAR

Steve CallanenPrivate Citizen/ Coastal Landowner

Nick CarterCooperative Oxford LaboratoryMaryland Dept. of Natural Resources

Thomas CarterMotiva Enterprises, LLC

Neil ChristersonNOAA, National Ocean Service

Thomas ChurchUniversity of Delaware

Sarah CookseyDNREC, Delaware Coastal Programs

Anthony DepasqualeU.S. Army Corps of EngineersPhiladelphia District

Richard DewanOffice of Dredging & Sediment TechnologyNJ Dept. of Environmental Protection

Delvin FanningUniversity of Maryland

Joseph FarrellDelaware Sea Grant Advisory Service

Brigitte FarrenU.S. EPA, Region 3

Thomas FikslinDelaware River Basin Commission

Lorraine FlemingDelaware Nature Society

Richard FlemingDelaware Nature Society

Tim GoodgerNational Marine Fisheries Service

Rick GreeneDNREC, Division of Water Resources

Randy GreerDNREC, Division of Soil & Water Conservation

Tom GroffU.S. Army Corps of EngineersPhiladelphia District

A

Hank GruberU.S. Army Corps of EngineersPhiladelphia District

Richard HasselU.S. Army Corps of EngineersPhiladelphia District

Simeon HahnNOAA

Bob HenryDNREC, Division of Soil & Water Conservation

Laura HerrDNREC, Division of Water Resources

Kerry KehoeCoastal States Organization

Forsyth KineonDelaware Estuary Program

Hank LloydMotiva Enterprises, LLC

Tony MacDonaldCoastal States Organization

Peter MartinDelaware Wild Lands

Evelyn MaurmeyerCoastal & Estuarine Research, Inc.

Roy MillerDNREC, Division of Fish & Wildlife

William MoyerDNREC, Division of Water Resources

Charles MyersU.S. Army Corps of EngineersPhiladelphia District

Kurt OlingerDNREC, Division of Air & Waste Management

Cornelia Pasche-WikarMaryland Dept. of Natural Resources

Jerry PasqualeU.S. Army Corps of EngineersPhiladelphia District

Tony PrattDNREC, Division of Soil & Water Conservation

Kelvin RamseyDelaware Geological SurveyUniversity of Delaware

H. Hickman RowlandWilmington Tug & Launch, Inc.

Maria SadlerDNREC, Division of Soil & Water Conservation

Jackie SavitzCoast Alliance

Robert ShantzMotiva Enterprises, LLC

Dan SirkisU.S. Army Corps of EngineersPhiladelphia District

Tom SlenkampUS EPA, Region 3

Mike SpragueDiamond State Port Corporation

Gary SmithDelaware Economic Development Office

Jim SteffensDelaware Sierra Club

Faye StocumState Historic Preservation Office

Jeff TinsmanDNREC, Division of Fish & Wildlife

Project Participants

Appendix A

Gregory TraceySAIC

Ron VickersDNREC, Division of Parks & Recreation

Charles WilliamsDNREC, Division of Soil & Water Conservation

Phil WirthVERSAR

Project Participants

Appendix A

CONTACT INFORMATION

Federal:

U.S. Army Corps of EngineersRegulatory Branch

Philadelphia District Baltimore DistrictWanamaker Building P.O. Box 1715100 Penn Square East Baltimore, MD 21203-1715Philadelphia, PA 19107-3390 410-962-1843215-656-6734

Dover Field Office302-736-9763

NOAA, National Marine Fisheries Service904 S. Morris StreetOxford, MD 21654410-226-5771

U.S. Environmental Protection AgencyRegion III1650 Arch StreetPhiladelphia, PA 19103-2029215-814-2719

U.S. Fish and Wildlife ServiceChesapeake Bay Field Office177 Admiral Cochrane DriveAnnapolis, MD 21401410-573-4500

State:

Department of Natural Resources and Environmental Control89 Kings HighwayDover, DE 19901

Division of Water ResourcesWetlands and Subaqueous Lands section 302-739-4691

B

Division of Soil and Water ConservationDelaware Coastal Programs Section 302-739-3451Sediment and Stormwater Section 302-739-4411

Division of Fish and Wildlife 302-739-5295

State Historic Preservation OfficeHall of Records121 Duke of York Street Suite 2Dover, DE 19901302-739-5313

Contact Information

Appendix B

THREATENED AND ENDANGERED SPECIES IN DELAWARE

Federal Listing of Threatened and Endangered Species(Source: U.S. Fish and Wildlife Service)

Status CodesT ThreatenedE EndangeredXN Experimental population Non-essential

Animals

Status Common Name Scientific NameT Eagle, bald Haliaeetus leucocephalusT Plover, piping Charadrius melodusE Puma, eastern Puma concolor couguarT Sea turtle, green (except where endangered) Chelonia mydasE Sea turtle, hawksbill Eretmochelys imbricataE Sea turtle, Kemp’s ridley Lepidochelys kempiiE Sea turtle, leatherback Dermochelys coriaceaT Sea turtle, loggerhead Caretta carettaE Squirrel, Delmarva Peninsula fox

(except Sussex Co., DE) Sciurus niger cinereusXN Squirrel, Delmarva Peninsula fox [XN] Sciurus niger cinereus

E Sturgeon, shortnose Acipenser brevirostrumT Turtle, bog (northern) Clemmys muhlenbergiiE Whale, finback Balaenoptera physalusE Whale, humpback Megaptera novaeangliaeE Whale, right Balaena glacialisPlants

Status Common Name Scientific NameT Pink, swamp Helonias bullataT Pogonia, small whorled Isotria medeoloidesE Dropwort, Canby’s Oxypolis canbyiT Beaked-rush, Knieskern’s Rhynchospora knieskernii

State Listing of Endangered Species of Delaware(Source: Delaware Natural Heritage Inventory June 12, 2000)

Amphibians

Common Name Scientific NameEastern Tiger Salamander Ambystoma tigrinum tigrinumBarking Treefrog Hyla gratiosa

C

Birds

Common Name Scientific NameBrown CreeperBR Certhia americanaBald Eagle Haliaeetus leucocephalusPied-billed GrebeBR Podilymbus podicepsNorthern HarrierBR Circus cyaneusCooper’s HawkBR Accipiter cooperiiBlack-Crowned Night-Heron Nycticorax nycticoraxYellow-Crowned Night-Heron Nyctanassa violaceaNorthern ParulaBR Parula americanaPiping Plover Charadrius melodusShort-eared OwlBR Asio flammeusAmerican Oystercatcher Haematopus palliatusBlack Rail Laterallus jamaicensisUpland Sandpiper Bartramia longicaudaLoggerhead Shrike Lanius ludovicianusBlack Skimmer Rynchops nigerSparrow, Henslow’s Ammodramus henslowiiCommon TernBR Sterna hirundoForster’s TernBR Sterna forsteriLeast Tern Sterna antillarumCerulean Warbler Dendroica ceruleaHooded WarblerBR Wilsonia citrinaSwainson’s Warbler Limnothlypis swainsoniiRed-headed Woodpecker Melanerpes erythrocephalusSedge Wren Cistothorus platensis

Fish

Common Name Scientific NameAtlantic Sturgeon Acipenser oxyrhynchus

Insects

Common Name Scientific NameLittle White Tiger Beetle Cicindela lepidaWhite Tiger Beetle Cicindela dorsalisSeth Forest Scavenger Beetle Hydrochus spp.Frosted Elfin Incisalia irusBethany Firefly Photuris bethaniensisHessel’s Hairstreak Mitoura hesseliKing’s Hairstreak Satyrium kingiRare Skipper Problema bulentaMulberry Wing Poanes massasoit chermocki

Threatened and Endangered Species in Delaware

Appendix C

Mammals

Common Name Scientific NameDelmarva Fox Squirrel Sciurus niger cinereus

Mollusks

Common Name Scientific NameYellow Lampmussel Lampsilis cariosaEastern Lampmussel Lampsilis radiataDwarf Wedgemussel Alasmidonta heterodonEastern Pondmussel Ligumia nasutaBrook Floater Alasmidonta varicosaTidewater Mucket Leptodea ochracea

Reptiles

Common Name Scientific NameLeatherback Sea Turtle Dermochelys coriaceaAtlantic Ridley Sea Turtle Lepidochelys kempiiGreen Sea Turtle Chelonia mydasLoggerhead Sea Turtle Caretta carettaBog Turtle Clemmys muhlenbergiiCorn Snake Elaphe guttata guttata

Threatened and Endangered Species in Delaware

Appendix C

PERMIT APPLICATION FORM

For Subaqueous Lands, Wetlands, Marinaand 401 Water Quality Certification Projects

State of DelawareDepartment of Natural Resources

and Environmental ControlDivision of Water Resources

Wetlands and Subaqueous Lands Section

Revised November, 2000

D

PERMIT APPLICATION FORM

FOR SUBAQUEOUS LANDS, WETLANDS, MARINA AND 401WATER QUALITY CERTIFICATION PROJECTS

IS NOT AVALIABLE IN PDF FORMAT.

PLEASE CONTACT THE DEPARMENT OF NATURALRESOURCES AND ENVIRONMENTAL CONTROL,

DIVISION OF WATER RESOURCES, WETLANDS ANDSUBAQUEOUS LANDS SECTION

TO OBTAIN THIS FORM.

PORT OF WILMINGTON

Background

The Port of Wilmington was purchased from the City of Wilmington by the State of Delaware inSeptember 1995. The Diamond State Port Corporation (DSPC) was established as a publicinstrumentality of the State to own, operate, and maintain the Port. The Corporation’s mission statementis:

“To contribute to Delaware’s economic vitality by sustaining and promoting thePort of Wilmington as a competitive and viable full service, multi-modal operationproviding for the efficient, economic, and safe handling of cargo.”

The Port is an important part of the local and regional economy, generating over 4,000 jobs andcontributing over $14 million in annual tax revenues to State and local governments.

The Port of Wilmington is situated on the southern bank of the Christina River, where it joins theDelaware River. Along the Delaware River, it is the major inland port closest to the Atlantic Ocean.The berthing facilities of the port consist of a marginal wharf (3,060 feet long), a floating berth forvehicles loading and unloading (510 feet long), and a tanker berth (960 feet long).

The Port services container, break-bulk, ro/ro and bulk commodities, through a combination of openstorage areas and over 810,000 square feet of warehousing. The majority of the warehousing holdsfruit and other chilled cargoes. In addition to the on-site storage, several commodities, including dryand liquid bulk products, as well as some ro/ro, are transferred off-site for storage by independentoperators.

Dredging

The Wilmington Harbor includes a shipping channel approximately 6200 feet in length and 440 feetwide. A ship turning basin to the north side of the channel measures 2900 feet long and 320 feet wide.

The channel and turning basin are dredged to a depth of 38 feet from the Delaware River west for adistance of 4240 feet. The remainder of the channel is dredged to 35 feet. Approximately 1.1 millioncubic yards of maintenance material are removed annually from the Christina River by the Corps ofEngineers, Philadelphia District in order to maintain the depths necessary for ships using the WilmingtonMarine Terminal. The dredging occurs on an eight or nine-month cycle, and is performed by contractedhydraulic pipeline dredges.

The Port of Wilmington dredges approximately 125,000 cubic yards of material annually between theFederal channel and their docking facilities. This dredging, like the Federal work, is performed byhydraulic pipeline dredges. The material is confined in the Federally owned sites at Wilmington Harbor.The Port pays the Corps a fee for private utilization of these areas.

Currently, two projects disposal areas, both Government owned, are available for the containment of

E

dredged material removed from the project. These sites are Wilmington Harbor (North) and Wilmington(South) disposal areas.

The table below reflects estimated capacity of each disposal area.

Estimated Capacity Last yr. to be Acres (cu yd)% Filled filled

Wilmington Harbor 145 3,500,000 90% 2005Wilmington South 240 13,000,000 40% 2019

The Port is currently working with the Corps to investigate the feasibility of deepening the channel to40 feet.

Recent costs to the Port of Wilmington for dredging and disposal have averaged $1.75 to $1.85 percubic yard. This has generally equated to an expense of $225,000 per dredge cycle. It should be notedthat this cost per cubic yard is extremely low compared to other ports.

Dredging Issues

1. With the impending loss of one disposal area, a replacement area or means for disposal of dredgedmaterial is essential to continued operations at the Port of Wilmington. The Corps of Engineers iscurrently evaluating alternatives for a new disposal area to replace Wilmington Harbor North.Informal discussions indicate that alternatives range from construction of a new upland confinementfacility, to pumping dredged material a greater distance to existing Government-owned disposalsites. Depending upon the Corps’ solution pursued, very significant cost impacts can accrue to thePort and the State of Delaware over many years.

2. Reduction in the rate of siltation in the Christina shipping channel can directly lead to reducedvolumes requiring confinement in disposal areas and lengthen useful life of a facility. The Corps ofEngineers is completing a hydrological study of current velocities, vectors, and other conditionswhich affect siltation in the Wilmington shipping channel. The purpose of this study is to determinewhether cost-effective solutions may exist to reduce siltation.

Beneficial re-use of dredged material could also lead to reducing volumes contained in disposal areas.Beneficial re-use should be pursued as a means to lengthen the life of Wilmington Harbor disposalareas. The Corps of Engineers has done extensive research into dredged material re-use to includeestablishment of pilot programs. Additionally, private firms are involved in exploring this arena.Successful beneficial re-use would benefit the Port of Wilmington and could potentially become arevenue source.

Port of Wilmington

Appendix E

the purpose of this statewide dredging policy …...the purpose of this statewide dredging policy...

Documents