investigating leaking underground storage...

Investigating Leaking

Underground Storage Tanks

A Practical Guide to Understanding Key Concepts

and Project Management

8/31/2015 LUST Training Module

Outline

Introduce key concepts

Identifying needs

◦ who, how

Outline of the process from discovery to

site closure

Understanding the results

Dealing with Contractors and

subcontractors

Video Clip


https://www.youtube.com/watch?v=cLHSCq9bz9s

Key Concepts

LUSTs are a major source of

environmental contamination

Usually discovered during a property sale

or permanent closure, or during equipment

replacement or monitoring

Sites can be very simple or complex

Involves soil, groundwater, surface water

and vapors


Pre-planning

Requirements for:

◦ Roles

◦ Personnel

◦ Workplace safety

◦ Waste Disposal

◦ Notification of release

◦ Interim actions


The Basics


Identifying Needs

Skills, technical capabilities needed

Internal roles and responsibilities

Establish clear lines of communication

Regulatory hierarchy


Possible Contractors

Site Assessor

Heavy Equipment Operator

Marine Chemist (inerting tanks)

Laboratory

TSD Facility

Land Surveyor

Utility Clearance

IDW Pickup

Perform Future Reviews (risk-based closures)


Identifying Needs

Who?

◦ Can develop and administer contracts/work orders

◦ Has a basic understanding of USTs

◦ Is aware of regulations governing USTs

◦ Is familiar with the field investigations and environmental contamination issues


Regulatory Considerations

EPA delegates RCRA programs to states, but retains the responsibilities for implementation in Indian Country

RCRA Subtitle I – the statutory authority and framework for regulation

40 CFR 280, 281 – the regulations to implement the statute and the state program approval

Federal government does not certify or license tank installers, removers or site assessors (states do).


Discovery


Helpful Documents


Expedited Site Assessment Tools for Underground Storage Tank Sites, A Guide for

Regulators. EPA 510-B-97-001. March 1997

How to Evaluate Alternative Cleanup Technologies for Underground Storage Tank Site, A

Guide for Corrective Action Plan Reviewers. EPA 510-B-95-007, May 2004.

Risk-Based Decision Making for Petroleum Releases at underground Storage Tank Sites in

Indian Country, Guidance Manual. Draft Final. May 2000.

Technical Guide for Addressing Petroleum Vapor Intrusion at Leaking Underground Storage

Tank Sites. EPA 510-R-15-001. June 2015.

Various guides from ASTM and API for conducting environmental site assessments

and corrective action.

◦ API Publications 1628 & 1629

◦ ASTM Guides E-1912, E-1599, E-1689, E-1739

State guidance documents

Commonly accepted good engineering practices

http://www.epa.gov/oust/pubs/esa-ch0.pdf

http://www.epa.gov/oust/pubs/tum_cvr.pdf

http://www.epa.gov/oust/cat/pvi/pvi-guide-final-6-10-15.pdf

Pre-planning

Review tank records.

Determine approximate

size & contents of the

tank(s).

Estimate number &

types of samples to be

collected.

Plan for contaminated

soil (if encountered).


DiscoveryTank Removal Discovery

“Site Assessor” observes the removal

Records observations

Samples are collected from around the tank, piping runs and dispensers if accessible.◦ Soil samples can be field

screened; and/or

◦ Submitted to laboratory for analysis

◦ Tank Removal Video


https://www.youtube.com/watch?v=5mupgPgwIxY

General Site Assessment Sampling

GuidelinesWhen and Where to Collect Soil

Samples

From both the floor and sidewalls of an

excavation

From soil that appears contaminated and

not

Native soil vs. backfill


Field ScreeningField screening will guide

the excavation of PCS

Laboratory samples should

be from discrete sampling

locations.


Sampling

Quality and Representative Samples

Collecting samples representative of site

conditions.

Since flammable, combustible or federally

regulated hazardous substances consist

largely of volatile organic compounds

(VOCs), care in collecting samples is

required.

◦ Hazard Awareness


Sampling ParametersSample

Analyses

Petroleum Mixture

Gasoline Diesel Waste

Oil

Fuel Oil Other* *

GRO X X

DRO X X X

PVOC X X X X

Naphthalene X X X X

Lead* X X

VOC* X X

PAH* X X

GRO – Gasoline Range Organics (State of Wisconsin)

DRO – Diesel Range Organics (State of Wisconsin)

PVOC – Petroleum Volatile Organic Compounds

VOC –Volatile Organic Compounds (BTEX, Additives)

PAH- Poly-Aromatic Hydrocarbons

* = Parameters selected if tank contents warrant

** = Other substances, parameter list may be expanded


Environmental Site Assessment


Environmental Site Investigation


Terminology

ASTM Phase 2◦ Confirms the presence of contamination

◦ Exploratory

Preliminary Assessement (Superfund)

Environmental Site Investigation (or Assessment)◦ Characterizes nature and extent of contamination

EPA guidance

American Petroleum Institute Guidance

Used to select or define an appropriate remedial or corrective action

Environmental Site Assessment


How to Guidance

EPA guidance (program specific)

American Petroleum Institute Guidance

ASTM Guides

State Guidance

What is it used for:

UST closure decisions

To select or define an appropriate cleanup

remedy or corrective action



Federal Requirements

40 CFR Part 280, Subpart F—

Release Response and Corrective

Action for UST Systems Containing

Petroleum or Hazardous Substances



§280.61 - Initial Response

(a) Report the release to the

implementing agency (e.g., by telephone

or electronic mail);

(b) Take immediate action to prevent any

further release of the regulated substance

into the environment; and

(c) Identify and mitigate fire, explosion,

and vapor hazards.




§ 280.63 Initial site

characterization

§ 280.65

Investigations for soil

and ground-water

cleanup.


Additional information needed before

developing an Request for Proposals (RFP)

◦ “General” local soil conditions

◦ Water table location

◦ Local utility conflicts

◦ Site history/use

◦ Regulatory heirarchy/permits

Uses data from the tank removal or

exploratory borings.EPA Expedited Site Assessment Guide


http://www.epa.gov/oust/pubs/sam.htm

Elements of an RFP Expected contaminants

Quality assurance or quality control requirements (EPA Quality System)

Required Deliverables

◦ QA/QC Plan (defensible results)

◦ Health and safety plan (OSHA requirement)

◦ Sampling & analysis plan

◦ Updates and regulatory correspondence

◦ Site Assessment Report

Bidder’s site visit ?


http://www.epa.gov/quality1/

Conducting the Environmental Site

Investigation Contractor creates a work plan showing

proposed workflow, reporting, soil boring and monitoring well locations (Conceptual Site Model)

◦ Based on:

Site elevation, expected groundwater flow direction

Known areas of contamination

Site features

Sampling and analysis plan

◦ Contaminant Sampling

◦ Sampling for Natural Attenuation


Conceptual Site Model

Essential part of project planning process

Serves to conceptualize the relationship

between contaminant sources and receptors

through contaminant transport pathways and

exposure scenarios

Presents current understand of site

Helps identify data gaps & focus future data

collection efforts

Presented in various ways including text, figures

and flow charts


Conceptual Site Model


A

“Good”

CSM

An

aly

tic D

ata

Site Models/Maps

LUST Training Module

Store

Removed tanks & lines

New tanks & lines

Groundwater

flow direction

Contaminated soil sample

Soil boring/Monitoring well

Pictorial CSM


Pathway-Receptor Network CSM


Another Example of a CSM


Field Activities Soil Sampling Video◦ (hollow stem auger & split

spoon)

Monitoring Well location and construction◦ Based on observations

made during soil boring installation

◦ Proper depth for well screen

◦ Special sealing and grouting

Groundwater Sampling


https://www.youtube.com/watch?v=xZQ0gftkF4U

https://www.youtube.com/watch?v=xWEKEYVTrqA&feature=related


Report Completed when nature and extent of

contamination defined

Contains:

◦ Maps (general, sample locations, contaminant plumes, groundwater flow direction)

◦ Tables of results (laboratory, field measurements)

◦ Soil boring logs

◦ Monitoring well Construction forms

◦ Laboratory data sheets

◦ Recommendation for remediation or corrective action


Remediation and Closure


Objectives of this Section

Cleanup Approaches

Cleanup Technologies

Guidance Documents

Feasibility Study

Technology Vendors

§ 280.66 Corrective action plan

§ 280.67 Public Participation


Guidance Documents


Cleaning up Underground Storage Tanks

◦ EPA Guidance Compendium

http://www.epa.gov/oust/cat/index.htm

Risk Based Corrective Action

◦ EPA Guidance

http://www.epa.gov/oust/rbdm/index.htm

◦ ASTM Guidance

http://www.astm.org/Standards/E1739.htm

http://www.epa.gov/oust/cat/index.htm

http://www.epa.gov/oust/rbdm/index.htm

http://www.astm.org/Standards/E1739.htm

Remediation

Based on findings of the environmental

site investigation

Level of activity dependent on the threat

to human health and the environment

◦ Risk Based Corrective Action (RBCA)

Dependent on future site use

No prescriptive alternatives

Cost/benefit analysis


Remediation

Types of remedial alternatives

◦ Dig and dump

◦ Pump and treat

◦ Air Sparging

◦ In-situ treatment

◦ Monitored natural attenuation

◦ Institutional controls

Tribal initiated clean ups

◦ Navajo Cleanup Video


https://www.youtube.com/watch?v=2KYg4jnHdk8&feature=relmfu

Remediation

When selecting a cleanup alternative,

pre-determine how clean is clean

◦ What screening standards will be used?

◦ Will they be site specific?

http://www.epa.gov/oust/cat/coc.htm


http://www.epa.gov/oust/cat/coc.htm

Remediation


“Dig and Dump”

Scale can vary

◦ Hot spot removal

◦ Removal to “Clean”

Disposal of soil

◦ Landfill, biopile, landfarming, soil burning, soil

washing

Placement and compaction of backfill

Utilities

Remediation


In-situ Treatments

Enhanced biodegradation

Air sparging

Remediation


Groundwater Treatments

Pump and treat technologies

◦ Air stripping

◦ Granular activated carbon

◦ Chemical treatment (mostly insitu)

Permits needed

◦ Air

◦ Water

Remediation


Monitored Natural Attenuation

◦ The term “natural attenuation” refers to

naturally-occurring processes in soil and

groundwater environments that act without

human intervention to reduce the mass,

toxicity, mobility, volume, or concentration of

contaminants in those media. These in-situ

processes include biodegradation, dispersion,

dilution, adsorption, volatilization, and

chemical or biological stabilization or

destruction of contaminants

Monitored Natural Attenuation


MNA

Bio

degr

adat

ion

Closure


Can take years to achieve

Remedial Goals achieved and

documented

◦ Institutional Controls for remaining

contaminants

Concurrence by EPA

◦ No Further Action (clean closure)

Thank you!

Presented by:

Rob Rau

U.S. EPA Region 10

Tribal UST/LUST Program

[email protected]

(206) 553-6285


mailto:[email protected]