northeast dayton area trunk & lateral sewer project ... · northeast dayton area trunk sanitary...

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ENVIRONMENTAL ASSESSMENT WORKSHEET

Note to reviewers: The Environmental Assessment Worksheet (EAW) provides information about a project that may have the potential for significant environmental effects. This EAW was prepared by the Minnesota Pollution Control Agency (MPCA), acting as the Responsible Governmental Unit (RGU), to determine whether an Environmental Impact Statement (EIS) should be prepared. The project proposer supplied reasonably accessible data for, but did not complete the final worksheet. Comments on the EAW must be submitted to the MPCA during the 30-day comment period which begins with notice of the availability of the EAW in the Minnesota Environmental Quality Board (EQB) Monitor. Comments on the EAW should address the accuracy and completeness of information, potential impacts that are reasonably expected to occur that warrant further investigation, and the need for an EIS. A copy of the EAW may be obtained from the MPCA by calling 651-297-8510. An electronic version of the completed EAW is available at the MPCA Web site http://www.pca.state.mn.us/news/eaw/index.html#open-eaw. 1. Project Title: Northeast Dayton Area Trunk and Lateral Sewer Project 2. Proposer: City of Dayton 3. RGU: Minnesota Pollution Control Agency Contact Person Mark Hanson Contact Person Chai Insook and Title City Engineer and Title Project Manager

Address Bonestroo, Rosene, Anderlik and Associates

Address

520 Lafayette Road North

2335 West Highway 36

St. Paul, MN 55155-4194

St. Paul, MN 55113 Phone 651-636-4600 Phone 651-296-7718 Fax 651-636-1311 Fax 651-297-2343 E-Mail [email protected] E-Mail [email protected] 4. Reason for EAW Preparation: EIS

Scoping

Mandatory EAW

X

Citizen Petition

RGU Discretion

Proposer Volunteered

If EAW or EIS is mandatory give EQB rule category subpart

number and name: 4410.4300, subpart 18, Item A Wastewater and Sewage Systems

“For expansion, modification, or replacement of a municipal sewage collection system resulting in an increase in design average daily flow of any part of that system by 1,000,000 gallons per day or more if the discharge is to a wastewater treatment facility with a capacity less than 20,000,000 gallons per day or for expansion, modification, or replacement of a municipal sewage collection system resulting in an increase in design average daily flow of any part of that system by 2,000,000 gallons per day or more if the discharge is to a wastewater treatment facility with a capacity of 20,000,000 gallons or greater, the PCA shall be the RGU.”

http://www.pca.state.mn.us/news/eaw/index.html#open-eaw

mailto:[email protected]

mailto:[email protected]

Northeast Dayton Area Trunk Sanitary Sewer Project Environmental Assessment Dayton, Minnesota 2 Worksheet

5. Project Location: County Hennepin City/Twp Dayton 1/4 1/4 Section See below Township 120 North Range 22 West

The project extends through or along the borders of Sections 10, 11, 14, 15, 16, 22, 23 T120N, R22W. Attachments and Figures for the EAW: Attachments:

Attachment 1 City of Dayton Sanitary Sewer Phasing Plan Map Attachment 2 Minnesota Department of Natural Resources (DNR) Natural Heritage and Nongame

Research Program Response Letter, dated November 14, 2006 Attachment 3 National Pollutant Discharge Elimination System (NPDES) Construction Stormwater

Permit Program Overview

Attachment 4 Minnesota Historical Society State Historic Preservation Office (SHPO) Responses to Inquiries dated November 3 and November 17, 2006

Figures:

Figure 1 General Project Location Figure 2 U.S. Geological Survey Topographic Map – Anoka, Minnesota Quadrangle

Figure 3 Service Areas Figure 4 National Wetlands Inventory Figure 5 Delineated Wetlands and Proposed Impacts

Figure 6 Public Waters Inventory/Federal Emergency Management Agency Floodplain Figure 7 Water-Related Land Use Management Districts Figure 8 Soils Figure 8A Soils Legend Figure 9 Recreational Features in Project Area

6. Description:

a. Provide a project summary of 50 words or less to be published in the EQB Monitor.

The city of Dayton (Dayton or City) is proposing to construct its Northeast Dayton Area Trunk and Lateral Sewer Project (Project). This sanitary sewer extension project is needed to provide sanitary sewer service to existing and future developments in northeast Dayton. It would also make future expansions of sewer services to the rest of northern Dayton possible. The Project would involve the construction of a lift station and approximately 64,000 linear feet of trunk and lateral sewer lines. The trunk lines are designed such that sewage would flow by gravity. However, a short segment of force main would be needed at the lift station. The sewer system would be designed with an average daily flow capacity of 2.4 million gallons per day (MGD). This flow would be routed through the Metropolitan Council Environmental Services (MCES) Dayton-Champlin Interceptor and discharged to the Metropolitan Wastewater Treatment Plant in accordance with Dayton’s Comprehensive Sanitary Sewer Plan (December 2005) (CSSP).


b. Give a complete description of the proposed project and related new construction. Attach additional sheets as necessary. Emphasize construction, operation methods and features that will cause physical manipulation of the environment or will produce wastes. Include modifications to existing equipment or industrial processes and significant demolition, removal or remodeling of existing structures. Indicate the timing and duration of construction activities.

The proposed system will eventually provide sanitary sewer coverage to approximately 5,000 residential and non-residential acres in the Project area. The design average daily flow of the system will be 2.4 MGD, based on wastewater generation of approximately 4,600 gallons per acre per day. The flow will be routed through the MCES Dayton-Champlin Interceptor and will discharge to the Metropolitan Wastewater Treatment Plant for processing. The general Project location is shown on Figure 1. The proposed alignments for the trunk line and the lateral lines are shown on Figure 2. The initial and ultimate service areas for the Project are shown on Figure 3. To minimize environmental impacts, the expansion of the sanitary sewer service will be completed in conjunction with expansion of the City’s water supply service and storm sewer service to the northeastern portion of Dayton. The water supply and storm sewer projects are designed in accordance with Dayton’s Draft Water Supply and Stormwater Comprehensive Plans. The sanitary sewer and water supply utilities are needed because existing developments have exceeded the allowable density for privately owned individual septic systems and water supply wells. The Project will involve the construction of a lift station and approximately 64,000 feet of PVC pipes. The trunk sewer pipes will range in size from 15 inches to 30 inches in diameter, and the lateral sewer will consist of eight-inch and ten-inch diameter pipes. The trunk line will connect to the future MCES Dayton-Champlin Interceptor at the Dayton/Champlin border. At this point, the flow rate will be measured at a meter station before entering the MCES interceptor system. From this point, the interceptor system will convey the wastewater to the Metropolitan Wastewater Treatment Facility in St. Paul. The system will be designed such that the wastewater will flow by gravity. However, a short segment of lateral pipe from the lift station will be force main. The lift station is needed to serve the portion of Stone Ridge Road, east of Pineview Lane, where a few of the homes are at elevations that cannot be served by a gravity flow system. The lift station will be located within the existing City right-of-way and will consist of dual pumps installed in a seven-foot diameter underground structure. Only a vent pipe and a concrete slab will be visible above ground. The lift station will have a design peak flow rate of 90 gallons per minute, which is adequate to lift the wastewater to an elevation where it can be discharged into the gravity flow system. The Project is anticipated to begin in May 2007 and be completed August/September 2008. Actual construction will involve grading, excavation, backfilling, potential de-watering, and re-vegetation activities. Equipment to be used will include standard construction machinery such as trucks, backhoes, graders, compactors, bobcats, cranes, loaders, compressors, and possibly de-watering pumps. In areas where the sewer follows a road, it is planned to be constructed within the road right-of-way. Because the installation of utilities will require digging in road, road resurfacing will be necessary after the completion of utility work.


c. Explain the project purpose; if the project will be carried out by a governmental unit, explain the need for the project and identify its beneficiaries. The proposed Project is needed to better manage wastewater from existing developments in northeast Dayton that date back to the 1960s and 1970s. Many of the existing homes are located on 15,000 square-foot lots that utilize individual on-site sanitary sewer treatment systems and wells. The density of the existing development has exceeded that which is allowed for privately owned individual septic systems and water supply wells, and connection to the new trunk and lateral sewer system will be required within five years of its construction. Initially, this would include the existing businesses and 577 homes in northeast Dayton. Ultimately, the trunk sewer will serve north Dayton in accordance with the Dayton CSSP.

d. Are future stages of this development, including development on any outlots, planned or likely to happen? Yes No If yes, briefly describe future stages, relationship to present project, timeline and plans for environmental review. The Project will initially serve the existing residents in the northeast part of Dayton. Ultimately, it will serve the entire northern part of the City as the northwestern part of Dayton develops in accordance with Dayton’s CSSP. In the future, additional lateral lines may be constructed to serve portions of northeast Dayton presently not developed. In addition, this Project would allow the construction of new trunk lines to serve other parts of northern Dayton. Construction of other trunk and lateral sewer systems will be driven by future development needs and requests, and would be subject to the City’s Sanitary Sewer Phasing Plan (see map in Attachment 1). If applicable, these future projects/developments may be subject to environmental review. As indicated, the trunk sewer is being designed in accordance with Dayton’s CSSP. The Dayton CSSP is divided into two main systems – the North and the West. The City’s CSSP system also contains three smaller areas referred to as Northwest, Southwest, and Southeast. Each system is designed to handle projected future growth based on the land use defined in the City’s comprehensive plan. This Project - The Northeast Dayton Area Trunk and Lateral Sewer Project - is the beginning of the North system.

Dayton also has sewer services that discharge to the trunk systems of neighboring communities, and are not planned at this time to be served by the proposed Project. These include:

• Diamond Lake Woods development - In 1996, a sanitary sewer extension was made from the city of Rogers to serve 50 existing residential homes located on the north side of Diamond Lake (Diamond Lake Woods development). This development will be connected to the Southwest Dayton trunk system (in the West Sanitary Sewer District) at some time in the future, when the southwest system is extended to serve other development in this area.

• Historic Village - In 1999, a sanitary sewer extension was made from the city of Otsego to serve the Historic Village in northwestern Dayton. This area will continue to discharge to the Otsego trunk system. At some time in the future, a portion of this area may be connected to Dayton’s North Sanitary Sewer District system.

• Nature’s Crossing development - In 2004, a sanitary sewer extension was made from the city of Champlin to serve the Nature’s Crossing development in Southeast Dayton. This area will continue to discharge to the Champlin trunk system.


• The Dayton Mobile Home Park (Dayton Park Properties MHP, approximately 225 units), located in the southwest corner of the City is served by its own treatment facility (MPCA Permit #MN00414321). This development will be connected to the Southwest Dayton trunk system (in the West Sanitary Sewer District) at some time in the future, when the southwest system is extended to serve other development in this area.

e. Is this project a subsequent stage of an earlier project? Yes No

If yes, briefly describe the past development, timeline and any past environmental review. The Northeast Dayton Area Trunk and Lateral Sewer Project would be an extension of the MCES Dayton-Champlin Interceptor, which was designed to bring Metropolitan Council sanitary sewer service to Dayton. The construction of the interceptor is anticipated to begin in 2007 and be complete in 2008, and would be able to accommodate average flows of 2.5 MGD. The Dayton-Champlin Interceptor alignment extends from the Dayton-Champlin border and follows French Lake Road, the future Tilden Avenue, Hayden Lake Road, Champlin Drive, proceeds under Trunk Highway 169 and connects to the Champlin-Anoka-Brooklyn Park (CAB) Interceptor west of Zealand Avenue North and Zealand Circle North. The Dayton-Champlin Interceptor is an extension of the CAB Interceptor. The Dayton-Champlin Interceptor project underwent environmental review through the MPCA in early 2005 and received a negative declaration on the need for an EIS. An environmental review was completed for the most recent phase of the CAB Interceptor in the mid 1980s, which also received a negative declaration on the need for an EIS by the MPCA.

7. Project Magnitude Data Total Project Area (acres) 73 acres or Length (miles) 12 miles (63,800 feet)

Number of Residential Units:

Unattached

0

Attached

0

Maximum Units Per Building:

NA

Commercial/Industrial/Institutional Building Area (gross floor space): total square feet

0

Indicate area of specific uses (in square feet):

Office 0 Manufacturing 0 Retail 0 Other Industrial 0 Warehouse 0 Institutional 0 Light Industrial 0 Agricultural 0 Other Commercial (specify) 0 Building height NA If over 2 stories, compare to heights of nearby buildings NA

The total length of the Project includes approximately 24,000 feet of trunk sewer lines and 39,800 feet of lateral sewer lines confined to the initial Project service area of 1,070 acres (see Figure 3). The Project will temporarily disturb approximately 73 acres of land. This estimate is based on the total length of the sewer lines and the typical construction corridor width of 50 feet. The Project area also includes the small lift station within City right-of-way in the northwestern part of the Project area, and three small staging areas on City-owned property for storage of equipment and materials.


8. Permits and approvals required. List all known local, state and federal permits, approvals and

financial assistance for the project. Include modifications of any existing permits, governmental review of plans, and all direct and indirect forms of public financial assistance including bond guarantees, Tax Increment Financing and infrastructure.

Unit of Government Type of Application Status U.S. Army Corps of Engineers Wetland/Water Project – Public Linear

Utility Project (GP/LOP-98-MN-Section 404 Activities in Minnesota)

Application to be submitted

MPCA 401 Water Quality Certification Application to be submitted MPCA NPDES General Permit for Discharge

of Stormwater During Construction Activities


MPCA Notice of Termination Notice to be submitted when construction and restoration activities have been completed

MPCA Sewer Extension Permit Application to be submitted DNR General Permit 97-0005 for Temporary

Water Appropriations Application to be submitted if needed

DNR Wetland/Water Project – Public Linear Utility Project (Public Waters Work Permit)

Application to be submitted if needed

DNR License to Cross Public Lands and Waters


Minnesota Department of Health (MDH)

Water Well Permits Application to be submitted (if dewatering wells are necessary)

Hennepin County Highway Department

Utility Permit for work within County Road Right-of-Way and/or for County Road crossings


Elm Creek Watershed Management Commission c/o Hennepin County Environmental Services

Approval of Grading Plan, Sediment and Erosion Control Plan

Application submitted November 29, 2006

City of Dayton Application for Minnesota Wetland Conservation Act (WCA) Certificate of No Loss or Exemption for temporary wetland impacts



9. Land use. Describe current and recent past land use and development on the site and on adjacent

lands. Discuss project compatibility with adjacent and nearby land uses. Indicate whether any potential conflicts involve environmental matters. Identify any potential environmental hazards due to past site uses, such as soil contamination or abandoned storage tanks, or proximity to nearby hazardous liquid or gas pipelines. Land Use Current land uses in the Project area are generally rural residential and agricultural. It is anticipated that some of the larger parcels of land may be subdivided and developed to higher density uses in the future. The Project is compatible with these existing and proposed land use plans. The proposed Project extends primarily through residential neighborhoods and small areas of commercial development. The alignment will cross Old Orchards Park and Hayden Hills Golf Course, and pass along the edges of agricultural lands and several City parks: Central Park, Donahue Dells Park, Dayton Highlands Park, and Riversbend Park. These nearby features are discussed in item 25. Potential Contamination A search was conducted of MPCA on-line records of potential contamination in the City to determine the potential for contamination to be encountered during construction of the Project. One record was found for Raintree Dental on Balsam Lane, the location of one of the lateral lines. The MPCA records indicate the business is registered as a RCRA TSD site (a RCRA TSD site is permitted to treat, store or dispose of hazardous waste). For dental offices such as Raintree, the waste is likely to be a small volume associated with typical dental activities involving silver fillings, x-ray processing, etc. It is unlikely that activities at this site would result in contamination impacts to the Project corridor. Based on preliminary investigative work completed for the proposed Project alignment (search of the MPCA records, knowledge of corridor land uses, and observations during the completion of soil borings), the potential for contaminated soils to be present along the Project corridor appears to be low. However, it is possible that undocumented contamination may be present in the Project corridor and may be encountered during excavation. If unanticipated contamination is encountered during construction, the State Duty Officer will be notified and proper procedures will be followed. These procedures may be addressed in a health and safety plan and/or a contingency plan prepared by the contractor. In addition, the Stormwater Pollution Prevention Plan (SWPPP) prepared for the Project as part of the NPDES Permit will address the proper response when contamination is encountered and/or caused by Project activities. The contractor will be required to follow the SWPPP. Additionally, the contractor will be made aware of the MPCA’s Petroleum Remediation Program Guidance Document 5-01 Managing Petroleum Contaminated Soil at Right-of-Way Utility Projects, which also provides guidance on the management of petroleum contaminated soil encountered during utility projects.

10. Cover Types. Estimate the acreage of the site with each of the following cover types before and after development:

Before After Before After Types 1-8 wetlands 2 acres 1.7 acres Lawn/landscaping 0 acres 0 acres Wooded/forest 1 acre 0 acres Impervious Surfaces 53 acres 53.3 acres Brush/grassland 1 acre 2 acres Other (describe) 0 acres 0 acres Cropland 16 acres 16 acres TOTAL 73 acres 73 acres


The above table shows the cover types along the proposed sanitary sewer route. Based on the total length of the sewer lines and the typical construction corridor width of 50 feet, the Project has the potential to temporarily disturb approximately 73 acres land. The Project will result in one acre of woodland being converted to grassland. Other than this land use conversion, no other permanent change to pre-construction cover type is expected to occur due to construction of the proposed Project.

The sanitary sewer project will temporarily disturb approximately 0.8 acres of wetlands (Figure 5). However, the City’s road work project that will follow the sanitary sewer work will result in the permanent filling of approximately 0.3 acres of wetlands along South Diamond Lake Road. See Item 12 for discussion of wetland impacts, minimization, and mitigation.

11. Fish, Wildlife, and Ecologically Sensitive Resources. a. Identify fish and wildlife resources and habitats on or near the site and describe how they would

be affected by the project. Describe any measures to be taken to minimize or avoid impacts. Wildlife habitat in the Project area consists of scattered wooded areas, wetlands, and the Mississippi River. Although the sewer itself extends primarily through residential neighborhoods and small areas of commercial development, the alignment also extends through a City park and a golf course, and will pass near several City parks and some properties still in agricultural use. Other potential habitat areas near the proposed Project include Diamond Creek to the southwest, Elm Creek to the south and southeast, and Elm Creek Park Reserve to the south. Due to the proximity of the Project to the Mississippi River and other habitats mentioned above, fish and wildlife species in the area may be more diverse than would typically be found in urban areas. Species might include: fox, deer, muskrat, rabbit, mice, and other small rodents, geese, ducks, and other waterfowl, eagles, hawks, and other raptors, wild turkey, a variety of other bird species, and reptiles. Amphibians and fish would also likely be present in and near the Project area in the river, creeks, and wetlands. However, the Project is not expected to have an impact on aquatic species or habitat. Short-term impacts on wildlife will include the disruptive effects of construction, including excavation, stockpiling of soils and materials, noise, potential erosion and sedimentation, and vehicle movement. Habitat and individual animals will be destroyed by the actual excavation or placement of stockpiled earth or bedding. Surviving small species may be forced to leave their territories and compete with established individuals in other areas. Larger species may be forced to relocate to portions of their territories that are not impacted. Seasonal activities, such as nesting, may be disrupted or curtailed, depending upon the season of construction. The Project itself will not permanently displace wildlife. However, urban development enabled by the sanitary sewer line will cause a shift in the species present. Species tolerant of urban areas will remain, while others less tolerant will not. Adherence to comprehensive plans and storm water ordinances adopted by the Elm Creek Watershed Management Commission and the City will mitigate storm water impacts resulting from development. Permits and approvals requiring mitigation measures include the NPDES General Permit for Discharge of Stormwater During construction Activities, the Elm Creek Watershed Management Commission approval of the Grading Plan and Sediment and Erosion Control Plan, and the Certificates of Exemption for temporary wetland impacts to be obtained from the local government unit (LGU), if applicable. These, and other permits listed in Item 8 of this EAW, will include specific mitigation measures to be provided for erosion and sediment control, stormwater runoff, and potential wetland impacts. Best management practices, such as the use of erosion control blankets


and prompt re-vegetation of disturbed areas, will be incorporated into the Project (see Item 16). Construction will have temporary impacts to some wetlands. See Item 12 for discussion of wetland impacts, minimization and mitigation. Construction through wooded areas will also occur, resulting in the conversion of approximately one acre of woodland (approximately 870 lineal feet) to grassland after construction.

b. Are any state (endangered or threatened) species, rare plant communities or other sensitive ecological resources such as native prairie habitat, colonial water bird nesting colonies or regionally rare plant communities on or near the site? Yes No

If yes, describe the resource and how it would be affected by the project. Indicate if a site survey of the resources has been conducted and describe the results. If the DNR Natural Heritage and Nongame Research program has been contacted give the correspondence

reference number: ERDB 20070342

Describe measures to minimize or avoid adverse impacts. The DNR Natural Heritage and Nongame Research Program was contacted regarding the potential presence of threatened or endangered species, as well as other rare or sensitive biological resources in the vicinity of the Project. According to the response received (see Attachment 2), there are 11 known occurrences of rare species or natural communities in the vicinity of the Project site. Of the 11 occurrences, the DNR felt that one, the Blanding’s Turtle, has the potential to be impacted by the Project. The Blanding’s Turtle is a state threatened species and the Project area is partially located within an area considered by the DNR to be of state-wide importance to Blanding’s Turtles. The Blanding’s Turtle population is declining due to factors such as wetland drainage and degradation, development on upland nesting areas, encounters with vehicles when trying to cross roads, and possibly collection for the pet trade. With the response letter, the DNR included recommendations for avoiding and minimizing impacts to the Blanding’s Turtle. Because the Project corridor includes an area that is of state-wide importance to the Blanding’s Turtle, both columns of recommendations to minimize and avoid impacts are recommended to be followed. The full list of recommendations is included with the DNR letter in Attachment 2. Recommendations specifically applicable to the proposed Project include:

• Distribute a flyer with an illustration of the turtle to all construction workers. • Move turtles in imminent danger out of harm’s way; leave others undisturbed. • Set up silt fencing to keep turtles out of construction areas; remove silt fencing after

construction is complete and areas have been re-vegetated. • Protect wetlands from pollution and erosion. • Keep utility access and maintenance roads to a minimum in order to reduce the potential for

road kill. • Below-ground utility construction sites should be returned to original grade as trenches may

trap turtles. • Re-vegetate graded areas with native grasses and forbs.

The Project will comply with the DNR recommendations listed above, as well as the recommendations specific to areas of state-wide importance, where feasible. While silt fencing will be utilized in several areas during Project construction, it is cost-prohibitive to install it along the entire Project length to keep turtles out of construction areas. Generally, silt fences installed for construction will be removed after construction is completed and surface


stabilization has been established. In potential nesting areas, silt fences will be installed with J hooks to allow the turtles some points of passage between upland and wetland areas. Additionally, silt fences installed in nesting areas will be removed by August 1 if surface stabilization has been established in these areas. In addition to implementation of the recommendations, stormwater management and erosion control measures (as required by the permits listed in Item 8) will also help to minimize impact to the turtle and other wildlife species and their habitat. See Item 16 for a discussion of the measures to be implemented. Although long-term impacts to the Blanding’s Turtle will not result directly from construction of the Project, long-term impacts to its habitat will result from construction of the development enabled by the trunk sewer. Blanding’s Turtles typically overwinter in lakes, spend spring and summer in shallower wetlands, and lay their eggs in sandy uplands. They may travel considerable distances to nesting areas. Future development may impact wetland areas and areas used for nesting. In addition, construction of roads and fences may interfere with migration of the turtle. Increased road traffic and road development could also result in greater road kill of the turtle. As a result, if there is a turtle population present in the area of the proposed Project, it is likely to decline as development of the area proceeds.

12. Physical Impacts on Water Resources. Will the project involve the physical or hydrologic alteration

(dredging, filling, stream diversion, outfall structure, diking, and impoundment) of any surface waters such as a lake, pond, wetland, stream or drainage ditch? Yes No If yes, identify water resource affected. Describe alternatives considered and proposed mitigation measures to minimize impacts. Give the DNR Protected Waters Inventory (PWI) number(s) if the water resources affected are on the PWI. The Project will involve construction adjacent to wetlands in some areas and construction through wetlands in others. National Wetlands Inventory wetlands are shown on Figure 4. Figure 5 shows the delineated wetlands and anticipated impacts (temporary and permanent). The alignments of both the sanitary sewer and the water supply lines will pass through a wetland on City-owned property (Old Orchard’s Park) in the central portion of the Project area, west of Pineview Lane and north of South Diamond Lake Road. The alignments do not follow a road in this area and approximately 0.8 acre of the wetland will be temporarily impacted. A trench box will be used for construction through the wetland to reduce the necessary trench width and minimize the impact. After construction, original grade and contours will be restored such that the pre-construction drainage patterns will not be altered by the Project. In addition, wetland vegetation will be restored by seeding with a native wetland seed mix. Trench dams will be utilized to prevent unintentional draining of the wetland due to the pipe trench potentially acting as a conduit. The sanitary sewer project will not result in permanent impacts to wetlands. However, the City’s concurrent road project will result in the loss of approximately 0.3 acres of wetland along the south side of South Diamond Lake Road (see Figure 5). Mitigation for the wetland impacts in this area will be completed with the purchase of banked wetland credits through the Minnesota Board of Water and Soil Resources road replacement program. Minimal impacts to four wetland areas along North Diamond Lake Road may occur during replacement of culverts in this area (see Figure 5). Impacts to other wetlands along the Project alignment (including DNR Public Water 27-278W shown on Figure 6) will be avoided. The ordinary high water level (OHW) for Public Water 27-278W has not been determined by the DNR and, therefore, the limit/boundary of the agency’s jurisdiction of the water body has not been established. The City will work with the DNR to


determine the OHW and to assess potential impacts. It is the City’s intent to avoid impacts to the public water. Minn. R. 8420.0122, subp.6a provides an exemption from wetland replacement for utilities/public works projects, such as this sanitary sewer project when the impacts will be temporary. Therefore, an application for a Certificate of No Loss or Exemption will be submitted to the LGU with regard to WCA approval of temporary wetland impacts. For projects in Dayton, the WCA LGU is the City. Approval for temporary impacts to wetlands will be obtained from the City as required prior to initiation of construction activities. Wetland areas where temporary impacts are proposed will be restored as previously described. Development enabled by the trunk sewer project will be subject to the WCA rules for replacement, as well as other permits and approvals required from the City, Elm Creek Watershed Management Commission, and/or the DNR. Potential wetland or other surface water impacts associated with future development in the area will be addressed during the planning and permitting processes of the City.

Dewatering may be necessary in some areas as discussed in Item 13. Discharge would be directed to sediment traps or vegetative buffer strips if the discharge is laden with sediment. A filter sock may also be used to trap the sediment and filter the water prior to discharge. If dewatering wells are needed, clean discharge from well point dewatering would be dissipated over the adjacent wetland areas located beyond the construction limits. If needed, the contractor would be responsible for obtaining permits for temporary dewatering wells and temporary water appropriations from the MDH and the DNR, respectively. An NPDES General Stormwater Construction Activity Permit will be obtained for the Project, as required from the MPCA. A SWPPP will be prepared as part of the permit for approval by the MPCA. Erosion and sediment control plans will also be submitted to the Elm Creek Watershed Management Commission for review and approval as required. Approved plans will be implemented during and after construction as appropriate until site stabilization has been achieved. The sediment and erosion control plans will provide more detail as to the specific measures to be implemented and will also address phasing of construction, vehicle tracking of sediment, inspection of erosion control measures, and the time frames in which the erosion control measures will be implemented (see Item 16 for more information).

13. Water Use. Will the project involve installation or abandonment of any water wells, connection to or

changes in any public water supply or appropriation of any ground or surface water (including dewatering)? Yes No If yes, as applicable, give location and purpose of any new wells; public supply affected, changes to be made, and water quantities to be used; the source, duration, quantity and purpose of any appropriations; and unique well numbers and DNR appropriation permit numbers, if known. Identify any existing and new wells on the site map. If there are no wells known on site, explain methodology used to determine. The proposed Project has the potential to affect water use in two ways:

1) Construction of the trunk and lateral sewer lines and lift station may require the relocation of existing wells to maintain isolation distances required by Minn. R. ch. 4725); and

2) Construction of the facilities will require dewatering during construction. Water appropriation permits would be required for withdrawals of or greater than 10,000 gallons per day or 1,000,000 gallons per year.

Separation Distance from Water Supply Wells City water service is being expanded to the Project area in conjunction with the proposed sewer project. A new City water tower, well, and water distribution lines will be constructed in accordance with Dayton’s Draft Water Supply and Distribution Plan, dated July 2006. As City water service is not


currently available in the Project area, the residences, farmsteads, and other developed properties in the area are currently served by individual private wells. Developed properties will be required to connect to the City water supply and sanitary sewer systems within five years of expansion of these services. Information from the MDH indicates that a minimum separation, or “isolation” distance, must be maintained between a well and a source of contamination to protect the well and the ground water. The distance applies to the construction of new wells, and to the placement of contamination sources near existing wells. The well rules contain specific isolation distances from contamination sources, such as petroleum tanks, chemical storage, septic systems, and sewers. A minimum separation of 50 feet must be maintained between a buried sewer and a well. This distance may be reduced to 20 feet if the sewer is constructed of cast iron or plastic pipe meeting the standards of the Well Code and the Minnesota Plumbing Code, and if the sewer has been successfully air tested. The separation requirement applies to all buried pipes carrying sewage, both outside a building, and under the building floor. The separation applies not only to wells used to provide drinking water, but also to wells used for other purposes, such as irrigation. At this time, it does not appear that abandonment of wells identified in the Project area will be needed due to the 50-foot separation requirement. A field survey will be completed to accurately determine the distances of wells on adjacent properties from the trunk and lateral sewer lines. Appropriate measures will be taken to maintain required separation distances, or if it is determined that water wells are present within minimum setbacks from the sewer alignments, they will be properly abandoned in accordance with MDH regulations. Because developed properties will be required to connect to the City water supply system within five years of its construction, the City does not anticipate replacing any wells that do not meet the required separation distance. Proper abandonment of individual private wells will be the responsibility of the well owner. Dewatering During Construction Soil borings were completed along much of the proposed Project alignment in September 2006. Water was encountered in 10 of the 22 borings, with depths to water measurements ranging from 7 to 31 feet below grade. In some of these areas, the water encountered may be perched, especially near wetlands. Trench dams will be incorporated into the Project to prevent unintentional draining of wetlands through or near which the alignment passes. The position of trench dams would depend on observed ground-water conditions. Soil borings will be used to identify perched wetlands created by horizontal confining layers that could be penetrated by the trench and drained. If necessary, a confining layer of low-permeability soils will be constructed to restore perched conditions. Temporary dewatering may be needed in some areas in order to place the sewer pipes at the required depths. Dewatering wells would be placed by the construction contractor based on the evaluation of dewatering needed. It is not yet known if the volumes of water would be such that a permit from the DNR would be required. The threshold for the DNR Water Appropriation Permit is 10,000 gallons per day, or 1 million gallons per year. The proposed Project may need a temporary permit – DNR General Permit 97-0005 for Temporary Water Appropriations. The threshold for this permit is also 10,000 gallons per day. Total gallons pumped cannot exceed 50 million gallons, and water appropriations must be completed within one year from the start of pumping. Where dewatering is necessary, discharge would be directed to sediment traps or vegetative buffer strips if the discharge is laden with sediment. A filter sock may also be used to trap the sediment and filter the water prior to discharge. If dewatering wells are needed, clean discharge from well point dewatering would be dissipated over the adjacent wetland areas located beyond the construction limits. If needed, the contractor would be responsible for obtaining permits for temporary dewatering wells and temporary


water appropriations from the MDH and the DNR, respectively. Temporary dewatering withdrawals would not be expected to have a negative impact on surface water bodies or ground-water supplies.

14. Water-related land use management districts. Does any part of the project involve a shoreland zoning district, a delineated 100-year flood plain, or a state or federally designated wild or scenic river land use district? Yes No If yes, identify the district and discuss project compatibility with district land use restrictions. The sanitary sewer project does not extend into areas designated as 100-year flood plain (see Figure 6), although two of the outlets for the City’s proposed stormwater improvements project extend into the 100-year flood plain of the Mississippi River as they discharge to the river. The entire City is located in the Elm Creek Watershed District, where the Elm Creek Watershed Management Commission has jurisdiction. The Mississippi River from St. Cloud to Anoka (including the portion of the river in the Dayton area) is designated a Wild and Scenic River. Portions of the proposed Project extend into areas zoned by the City as Critical Rivers Area District. Portions of the Project also extend into the Mississippi River Critical Area (Critical Area)/Mississippi National River and Recreation Area (MNRRA). The boundaries of some of these districts are the same, as discussed below. According to Dayton’s Zoning Ordinance, the more restrictive designation takes precedence. The proposed Project is compatible with the land use restrictions associated with the water-related management districts to which it is subject, and the Project is being designed in compliance with construction standards and guidelines associated with the districts. These standards and guidelines, however, apply more directly to traditional development projects and less so to underground utility projects. It is likely that developments enabled by this Project will be more directly subject to the standards and guidelines of the districts. Future development projects will be reviewed by the appropriate authority to determine compliance. Figure 7 shows the boundaries of the water-related land use management districts in relation to the City’s sanitary sewer project. As indicated, the entire City is located in the Elm Creek Watershed District. Therefore, the boundary of the Elm Creek Watershed District is not shown in Figure 7. Elm Creek Watershed District The Elm Creek Watershed Management Commission will review the grading plans and the erosion and sediment control plans (temporary and permanent) for the Project. They will also review the SWPPP prepared for the Project. Measures to prevent or minimize impacts to Elm Creek and other surface waters are discussed in Item 12 and Item 16. The Project will comply with the standards set forth by the Elm Creek Watershed Management Plan (2003). Minnesota Wild and Scenic Rivers Program The Mississippi River from St. Cloud to Anoka was added to Minnesota’s Wild and Scenic Rivers Program in 1976. The river is designated as “scenic” from St. Cloud to Clearwater, and “recreational” from Clearwater to the Anoka/Champlin line. Dayton is located along the stretch designated “recreational.” Recreational rivers are those rivers that may have undergone some impoundment or diversion in the past and that may have adjacent lands that are considerably developed, but that are still capable of being managed so as to further the purposes of the Wild and Scenic Rivers Act. This means that bordering lands may have already been developed for a full range of agricultural or other land uses, and may also be readily accessible by pre-existing roads or railroads. The original management plan for this area of the river was adopted in 1976. A Revised Management Plan was developed in 2004 by Minnesota citizens, local governments, and state agencies using a community-based planning approach. Existing rules (1997) identify the district boundary, minimum lot


sizes, types of development, setbacks, and other activities in order to protect the special scenic and recreational qualities of the river. The DNR is considering amending the rules to coincide with the 2004 management plan and has requested and received comments on the potential changes. The rule revision would give river cities greater flexibility for managing population growth within the river district. The DNR is considering the comments received and is expected to prepare a draft rule for public hearing in 2007. Cities and counties that have jurisdiction within the district would be required to amend their local ordinances to implement the amended rules. The rules indicate that for “that portion of the wild and scenic river district within the cities of Ramsey and Dayton, which coincides with the Mississippi River Critical Area,” the cities are subject to the land use and dimensional requirements of DNR and Metropolitan Council-approved local ordinances adopted as part of the Critical Area, as described in Executive Order 79-19. Critical Area/MNRRA Portions of the Project extend within the federal MNRAA, established in 1988 and overseen by the National Park Service, and the state Critical Area Program, established in 1976 and overseen by the DNR. The boundaries of the two designations are the same. The Critical Area/MNRRA corridor stretches from Ramsey and Dayton, Minnesota, to the southern boundary of Dakota County on the west/south side of the river and the boundary with the Lower St. Croix National Scenic Riverway on the east/north side of the river, and runs through the heart of Minneapolis-St. Paul. The corridor includes 72 miles of the Mississippi River, four miles of the Minnesota River, and 54,000 acres of adjacent corridor lands. The Critical Area Program is a joint local and state program that provides coordinated planning and management for the corridor. The purposes of designating the Mississippi River as a critical area include protecting and preserving a unique and valuable state and regional resource; preventing and mitigating irreversible damage to this resource; preserving and enhancing its natural, aesthetic, cultural, and historical value for public use; protecting and preserving the river as an essential element in the national, state and regional transportation, sewer and water and recreational systems; and protecting and preserving the biological and ecological functions of the corridor. Under the Critical Area Program, Executive Order 79-19 provides standards and guidelines and requires adherence by local units of government, state agencies, and regional agencies when developing plans and regulations, and when permitting and approving development plans within their jurisdiction affecting lands within the corridor. Once plans and regulations have been approved by the DNR, local units of government shall permit development only in accordance with those adopted plans and regulations. All capital improvement programs or public facilities programs of local units of government, regional agencies, and state agencies that affect lands within the corridor are required to be consistent with the standards and guidelines in the Critical Area Executive Order 79-19. The proposed Project is consistent with the standards and guidelines, as adopted by the City.


The MNRRA is a partner park that offers traditional outdoor activities alongside a wide variety of high quality, city-based visitor centers, programs, and activities. It is a place where the National Park Service works with other agencies to preserve, enhance, and make special places available to visitors by working with other agencies. The National Park Service owns 35 of the approximately 54,000 acres within the MNRRA boundary. The rest is owned and managed by partner agencies. The National Park Service has issued guidance regarding land use and development within the MNRRA, but does not have permitting authority. The National Park Service also worked with other agencies to develop a comprehensive management plan (1995) to guide land use within the MNRRA. The MNRRA Comprehensive Management Plan “adopts and incorporates by reference the state critical area program, shore lands program, and other state and regional land use management programs that implement the visions and concepts identified for the corridor.” The plan indicates that local government is to retain local control of land use decisions in the corridor, consistent with applicable state and regional land use management programs. The plan also indicates that it “will not prevent new development or expansion of existing development in the corridor that is consistent with state and regional land use management programs. It is not a regulatory document and does not mandate actions by non-NPS entities. The National Park Service and the commission do not have approval authority over local plans and ordinances, and they do not have authority to approve or deny project-specific land use decisions.” Critical Rivers Area District As indicated, the City has zoned the land within the Critical Area as a Critical Rivers Area District. The boundaries of the two are the same. The Critical Rivers Area District zoning is designed to add controls and standards within the critical river area along the Mississippi River in a location as defined by the State of Minnesota to preserve and enhance the river and its associated natural, aesthetic, cultural, and historic values. The Critical Rivers Area District is an overlay district, which means other zoning designations may also apply to land within the area. The City’s zoning ordinance indicates that projects to be constructed in the Critical Rivers Area District must minimize runoff on site, control the rate and quantity of runoff off site, maintain or improve water quality, utilize and maintain best management practices, such as those recommended in the MPCA’s “Protecting Water Quality in Urban Areas,” and meet all applicable NPDES requirements. Utilities should be placed underground in order to minimize visual impact and should avoid slopes greater than 18 percent, wetlands, woodlands, and areas of unstable soils. Vegetation is to be restored after construction of the utilities. The proposed sanitary sewer project is consistent with the zoning requirements, although a portion of the City’s storm sewer project will involve removing an existing storm sewer pipe draining into the river and replacing it with a pipe installed deeper and at a flatter grade. The replacement of this pipe will require the excavation of an existing 30 percent slope from Overlook Road down to the waters edge within the Critical River Boundary. The replacement pipe will be an improvement over the existing pipe because the outflowing water will be moving much slower at the point of discharge, which will reduce future erosion. Shoreland Zoning District The City has adopted special zoning for shoreland areas, although no portion of the Project will be located within a shoreland zoning district. The Shoreland District is designed to add controls and standards to ensure wise preservation, use and development of shorelands of public waters as classified by the DNR. The Shoreland District is an overlay district, which means other zoning designations may also apply to land within the area. A shoreland protection zone generally includes land within 1,000 feet of a lakeshore (technically it is 1,000 feet from the ordinary high water level of a lake, pond, or flowage) and land within 300 feet of a river or stream, or the landward extent of a flood plain designated by ordinance on a river or stream, whichever is greater. The shoreland protection zone embodies DNR standards for protection of a water resource from development impacts.

15. Water Surface Use. Will the project change the number or type of watercraft on any water body?


Yes No If yes, indicate the current and projected watercraft usage and discuss any potential overcrowding or conflicts with other uses. The Project itself will not change the number of watercraft on any water bodies in the Project area.

16. Erosion and Sedimentation. Give the acreage to be graded or excavated and the cubic yards of soil to be moved: 73 acres; 1 million cubic yards. Describe any steep slopes or highly erodible soils and identify them on the site map. Describe any erosion and sedimentation control

measures to be used during and after project construction. Two of the Lester loam soils in the western part of the Project area are identified as eroded - L22C2 and L22D2 (see Figure 8). With slopes of 12 to 18 percent, the L22D2 soil also exhibits steep slopes (generally regarded as greater than 12 percent). Steep slopes or bluff areas are also present along the Mississippi River, but the Project’s construction limits will not encroach into these areas. Topsoil that will be stripped in agricultural areas will be restored. The majority of excavated soil will be returned to the construction trench after placement of the pipe. Any excess soil will be disposed of in upland areas where sediment will not impact water resources or other sensitive areas. Soil erosion control practices will be implemented to minimize impacts to the Mississippi River, creeks, wetlands, and other surface waters in the vicinity of the Project. Best management practices will be observed. Construction practices will be managed to limit the duration of exposed soil to wind and rain. Disturbed areas will be seeded and stabilized as soon as possible after construction. Detailed temporary and permanent sediment and erosion control plans must be prepared in accordance with the MPCA NPDES General Storm Water Construction Permit. The erosion and sediment control plans, grading plans, and SWPPP will also be submitted for review and approval to the Elm Creek Watershed Management Commission, as required. Measures will be implemented prior to the start of construction and will remain in place until site stabilization has been achieved. Regular inspection will ensure that measures implemented remain effective. In general, high flow areas will be protected with turf reinforcement mats. Any potential high flows from off site will be mitigated as they enter the construction site. Specific measures to be implemented may include the use of high flow and standard silt fence, rock construction entrance, check dams, biologs, sedimentation or stilling basins, erosion control blankets, and prompt re-vegetation of disturbed areas via seeding and mulch. A fiber blanket or hydraulic seed stabilizer may also be used. Specific erosion control and stormwater management measures will be outlined in the SWPPP for the Project. The SWPPP will be submitted to the MPCA for review and approval as part of the NPDES Permit Application process, if required.


17. Water Quality – Surface-water Runoff. a. Compare the quantity and quality of site runoff before and after the project. Describe

permanent controls to manage or treat runoff. Describe any storm-water pollution prevention plans. The Project will require an NPDES Permit because it will disturb more than one acre of land. The NPDES Permit requires the preparation of an SWPPP, which includes both temporary and permanent erosion and sediment control plans. Attachment 3 contains an overview of the NPDES Construction Stormwater Permit program and lists the requirements. The Project will comply with NPDES Permit requirements. Because the sewer pipe will be buried, the quantity and quality of runoff before and after the Project will not change significantly. Discharge from dewatering activities during excavation is discussed in Item 13 and will be conducted as stipulated in applicable permits and approvals (see Items 8, 13, and 16).

b. Identify routes and receiving water bodies for runoff from the site; include major downstream water bodies as well as the immediate receiving waters. Estimate impact runoff on the quality of receiving waters. Receiving water bodies in the vicinity of the proposed Project include wetlands, Elm Creek, and ultimately, the Mississippi River. Though Diamond Creek is in the Project vicinity, the natural drainage of the area does not discharge to the creek. As discussed in Items 12 and 16, appropriate erosion and sediment control measures will be implemented during construction, and runoff from the site will be minimized. Because the sewer pipe will be placed below grade and because the disturbance will be temporary, no significant impacts to receiving water bodies are anticipated. Vegetation will be restored as soon as possible after construction. Fiber blankets, mulch and/or hydraulic seeding will be used, where necessary, to ensure prompt re-vegetation. The SWPPP and NPDES General Permit for Discharge of Storm Water during Construction Activities will outline specific time line provisions for re-vegetation (see Item 16). The contractor will comply with these time lines.

18. Water Quality – Wastewater. a. Describe sources, composition and quantities of all sanitary, municipal and industrial

wastewater produced or treated at the site. The Project will initially serve the existing residents in the northeast part of Dayton. Ultimately, it will serve the entire northern part of the City as the northwestern part of Dayton develops in accordance with Dayton’s Comprehensive Plan. The Project service areas are shown on Figure 3. The trunk sewer will be sized to accommodate wastewater flows of 2.4 MGD and will convey the sanitary wastewater to the MCES Dayton-Champlin Interceptor. The flows will discharge to the Metropolitan Wastewater Treatment Facility in St. Paul. The wastewater will be within the range of normal strength domestic wastewater.


b. Describe waste treatment methods or pollution prevention efforts and give estimates of

composition after treatment. Identify receiving waters, including major downstream water bodies, and estimate the discharge impact on the quality of receiving waters. If the project involves on-site sewage systems, discuss the suitability of site conditions for such systems. The Project’s service area within Dayton does not have centralized wastewater treatment and collection service. Existing developments have privately owned individual septic systems. As can be expected, an area relying on on-site wastewater treatment systems is not likely to be a candidate for high-strength wastewater generators. There are no permittees registered in the MCES Industrial Waste Permit Program in Dayton.

c. If wastes will be discharged into a publicly owned treatment facility, identify the facility,

describe any pretreatment provisions and discuss the facility’s ability to handle the volume and composition of wastes, identifying any improvements necessary. Pretreatment of the waste is not necessary. The Project will convey normal strength wastewater to the MCES Dayton-Champlin Interceptor, and then onward to the Metropolitan WWTF in St. Paul. The MCES Interceptor was designed to accommodate flows anticipated from northern Dayton and the Metropolitan treatment facility has ample capacity to accommodate the additional average daily flow of 2.4 MGD. The Metropolitan WWTF has a capacity of 251 MGD and is currently treating approximately 215 MGD. Expansion of the Metropolitan WWTF is anticipated within the next 20 years.

d. If the project requires disposal of liquid animal manure, describe disposal technique and location and discuss capacity to handle the volume and composition of manure. Identify any improvements necessary. Describe any required setbacks for land disposal systems. Not applicable – the Project does not involve disposal of liquid animal manure.

19. Geologic hazards and soil conditions. a. Approximate depth (in feet) to Ground water: See

below minimum; See

below average.

Bedrock: See below

minimum; See below

average.

Describe any of the following geologic site hazards to ground water and also identify them on the site map: sinkholes, shallow limestone formations or karst conditions. Describe measures to avoid or minimize environmental problems due to any of these hazards. According to the Geologic Atlas for Hennepin County (Minnesota Geological Survey, 1989), surficial geology in the Project area is comprised mainly of Middle Terrace deposits consisting of sand, gravelly sand, and loamy sand overlain by thin deposits of silt loam or organic sediment. Upper Terrace deposits are also present in the area. These deposits are comprised of the same sediment as the Middle Terrace, but are at a higher elevation. The western segments of the sewer project extend through loamy till deposits that are chiefly loam in texture with a few beds and lenses of stratified sediment. These deposits also include small areas of thick, fine, loamy colluvium. Organic deposits consisting of peat and organic-rich sediment are also scattered in the western parts of the Project area.


The underlying bedrock units in the area are the St. Lawrence Formation, comprised of dolomitic siltstone and shale, and the Franconia Formation, comprised of sandstone and shale. Other formations were here in the past but have been eroded away through years of glaciations. It appears that a bedrock valley is present beneath the Project site area. The depth to bedrock ranges from approximately 101-250 feet below the land surface in this area. Soil borings completed in September 2006 indicate that depth to ground water varies in the Project area. Water was encountered in 10 of the 22 soil borings at depths of 7 to 31 feet below grade. Ground water flows to the east/northeast according to the Quaternary Hydrogeology map in the geologic atlas. Within the bedrock aquifers, ground water in the area appears to flow to the northeast in the Franconia-Ironton-Galesville aquifer, and to the southeast in the Mt. Simon-Hinckley aquifer. Sinkholes, shallow limestone formations, karst conditions, or other geologic site hazards are not identified in the Project area by the geologic atlas or the soil borings.

b. Describe the soils on the site, giving SCS classifications, if known. Discuss soil granularity and potential for ground-water contamination from wastes or chemicals spread or spilled onto the soils. Discuss any mitigation measures to prevent such contamination. Soil types through which the Northeast Dayton Area Trunk Sewer and lateral lines will be constructed are listed in the following table. Any special considerations associated with the soil types are also indicated in the table. Soil Types Symbol Soil Name Special Significance D1B Anoka and Zimmerman soils, terrace,

2-6 percent slopes --

D6A Verndale sandy loam, acid substratum, 0-2 percent slopes

Farmland of statewide importance

D6B Verndale sandy loam, acid substratum, 2-6 percent slopes

Farmland of statewide importance

D7A Hubbard loamy sand, 0-2 percent slopes -- D7B Hubbard loamy sand, 2-6 percent slopes -- D7C Hubbard loamy sand, 6-12 percent slopes -- D8C Sandberg loamy coarse sand, 6-12 percent slopes -- D10A Forada sandy loam, 0-2 percent slopes Hydric, prime farmland where

drained D17A Duelm loamy sand, 0-2 percent slopes -- D20A Isan sandy loam, 0-2 percent slopes Hydric D23A Southhaven loam, 0-2 percent slopes Prime farmland D25A Soderville loamy fine sand, terrace,

0-3 percent slopes --

D26A Foldahl loamy sand, map >25, 0-3 percent slopes Farmland of statewide importance L22C2 Lester loam, morainic, 6-12 percent slopes,

eroded Farmland of statewide importance

- continued -


Symbol Soil Name Special Significance L22D2 Lester loam, morainic, 12-18 percent slopes,

eroded --

L23A Cordova loam, 0-2 percent slopes Hydric, prime farmland where drained

L24A Glencoe loam, depressional, 0-1 percent slopes Hydric, prime farmland where drained

L25A Le Sueur loam, 1-3 percent slopes Prime farmland L36A Hamel, overwash-Hamel complex,

1-4 percent slopes Hydric, prime farmland where drained

L37B Angus loam, morainic, 2-5 percent slopes Prime farmland L50A Houghton and Muskego soils, depressional,

0-1 percent slopes Hydric

Hydric soils were identified using the Hydric Soils of Minnesota list, revised December 1995. Farmland of statewide importance was identified using a list (dated January 23, 2004) previously obtained from Hennepin County Environmental Services. Soils designated as farmland of statewide importance are not considered prime, but are still considered of value for agricultural use. Prime farmland soil was identified using the Soil Survey of Hennepin County, Minnesota, issued in 2004 and available at: http://www.co.hennepin.mn.us/vgn/images/portal/cit_100003616/0/32/114134776hennepin_soil_survey_text.pdf. In general, water moves through coarse textured soils at a faster rate than through medium or fine textured soils. Therefore, potential impacts to ground water from spilled chemicals would be expected to be greater in the areas with coarse textured soils. However, many factors in addition to soil granularity can affect infiltration and percolation rates in soils. Some of these factors include: soil water content, soil frost, the temperature of the soil and water, surface roughness, the nature of the soil pore openings, vegetative ground cover, and the degree of soil compaction. Due to the nature of the Project, the potential for impacts to ground water is minimal after its construction. See Item 20b below for a discussion of potential releases during construction. Other than modifications to minimize impacts in wetland areas (as discussed in Item 12), construction activities will be fairly uniform throughout the Project. Care will be exercised in all aspects of construction activities to minimize the potential for accidental releases.

20. Solid Wastes, Hazardous Wastes, Storage Tanks. a. Describe types, amounts and compositions of solid or hazardous wastes, including solid animal

manure, sludge and ash, produced during construction and operation. Identify method and location of disposal. For projects generating municipal solid waste, indicate if there is a source separation plan; describe how the project will be modified for recycling. If hazardous waste is generated, indicate if there is a hazardous waste minimization plan and routine hazardous waste reduction assessments. Construction activities will generate waste materials, such as aggregate base, bituminous pavement, reinforced concrete pipe, concrete, PVC pipe, ductile iron pipe, fence wire and posts, survey stakes, silt fence, corrugated metal pipe, metal posts, signs, trees, and timber posts. These materials will be stored in designated staging areas and will be disposed of by the contractor in accordance with applicable state and local rules and regulations. Proper handling and disposal of these materials will also be mandated in the SWPPP.

http://www.co.hennepin.mn.us/vgn/images/portal/cit_100003616/0/32/114134776hennepin_soil_survey_text.pdf


b. Identify any toxic or hazardous materials to be used or present at the site and identify measures to be used to prevent them from contaminating ground water. If the use of toxic or hazardous materials will lead to a regulated waste, discharge or emission, discuss any alternatives considered to minimize or eliminate the waste, discharge or emission. During construction, equipment and vehicles utilizing gasoline, diesel fuel, antifreeze, and oil will be used at the Project site. Portable storage tanks of fuel may be temporarily located at the designated staging areas during construction. Fueling of vehicles and equipment will be conducted in upland areas and within the road or utility construction rights of way, away from water bodies and other sensitive areas. Although not anticipated, if a release were to occur, it would be handled in accordance with applicable regulation (contain the spill, make the appropriate notifications, etc.), such as Minn. R. 7045.0275 Management of Hazardous Waste Spills. Subparts 2 and 3 of this rule address the duty to report and the duty to recover releases of hazardous waste. In addition, the SWPPP prepared for the Project as part of the NPDES Permit will address the proper response when contamination is encountered and/or caused by Project activities. The contractor would be responsible for following proper procedure.

c. Indicate the number, location, size and use of any above or below ground tanks to store petroleum products or other materials, except water. Describe any emergency response containment plans. As discussed above, portable storage tanks of fuel may be temporarily located at the designated staging areas during construction.

21. Traffic. Parking spaces added: 0 Existing spaces (if project involves expansion): 0 Estimated total average daily traffic generated: NA Estimated maximum peak hour traffic generated (if known) and its timing: NA

Provide an estimate of the impact on traffic congestion affected roads and describe any traffic improvements necessary. If the project is within the Twin Cities metropolitan area, discuss its impact on the regional transportation system. Traffic will not increase due to construction of the Project. The only increase in traffic resulting directly from the Project would be that due to construction of the Project, and that due to maintenance of the sewer lines and lift station. During the construction process, construction vehicles will be utilizing county roads and local streets. Delivery of pipe, concrete and other materials will be restricted to county roads where possible, and use of local streets for this purpose will be avoided to the extent possible. Construction of the lateral lines will cause disruption on local streets. At times, some of the roads will be closed and detours will be needed. Traffic management will be addressed in the Project specifications and, where needed, a traffic control plan. Efforts will be made to minimize disruption. In the future, traffic in the vicinity of the Project will increase with increased urban development. Residential, commercial, and other types of development will be enabled as a result of the Project. It is the purpose of the Project to provide wastewater collection and conveyance for the Project service area, which immediately includes the northeast part of Dayton, but will ultimately include the entire northern part of the City (see Figure 3). As a result of increased development of these areas in the future, vehicular traffic will increase. The City of Dayton Comprehensive Plan, dated February 2001, includes a transportation plan. This plan will be updated when Dayton updates its Comprehensive Plan in 2008. It


will be necessary for the Minnesota Department of Transportation, Hennepin County, Metropolitan Council, and Dayton to work together to provide appropriate roadway improvements and measures to mitigate traffic congestion.

22. Vehicle-related Air Emissions. Estimate the effect of the project’s traffic generation on air quality, including carbon monoxide levels. Discuss the effect of traffic improvements or other mitigation measures on air quality impacts. Note: If the project involves 500 or more parking spaces, consult EAW Guidelines about whether a detailed air quality analysis is needed. Vehicle emissions directly associated with the Project will not have a significant effect on air quality. However, residential and other development enabled by the construction of wastewater conveyance capacity may result in measurable, but not likely significant impacts. If traffic increases due to the enabled development result locally in future deterioration in levels of service and/or air quality violations, mitigative measures are available. These measures include roadway improvements, signal installation, and provision of alternative transportation choices.

23. Stationary Source Air Emissions. Describe the type, sources, quantities and compositions of any emissions from stationary sources of air emissions such as boilers, exhaust stacks or fugitive dust sources. Include any hazardous air pollutants (consult EAW Guidelines for a listing), any greenhouse gases (such as carbon dioxide, methane, and nitrous oxides), and ozone-depleting chemicals (chlorofluorocarbons, hydrofluorocarbons, perfluorocarbons or sulfur hexafluoride). Also describe any proposed pollution prevention techniques and proposed air pollution control devices. Describe the impacts on air quality. There will be no stationary source air emissions associated with the proposed Project.

24. Odors, noise and dust. Will the project generate odors, noise or dust during construction or during operation? Yes No

If yes, describe sources, characteristics, duration, quantities or intensity and any proposed measures to mitigate adverse impacts. Also identify locations of nearby sensitive receptors and estimate impacts on them. Discuss potential impacts on human health or quality of life. (Note: fugitive dust generated by operations may be discussed at item 23 instead of here.) Dust and noise will be generated by equipment and machinery during construction. Odors may also be generated from construction equipment exhaust. Equipment will include trucks, backhoes, graders, compactors, bobcats, cranes, loaders, compressors, and possibly de-watering pumps. Dust will most likely be controlled by daily cleanup of the construction site. Water will be used to wet the soil and reduce airborne dust when necessary as determined by the site inspector. Noise and odor impacts from construction equipment will be controlled by restricting the hours of operation to daylight hours, or those permitted by local ordinances. After construction, the Project will not generate noise as the entire system will be below the ground. Portions of the Project (particularly the lateral lines) proceed through residential neighborhoods. Construction impacts will be confined to road right-of-way, but residents will experience some inconvenience. The City will make all reasonable efforts to minimize the inconvenience. Average exposure times are estimated to be approximately 60 days.


Odor issues that are common during turbulent flow conditions are not expected to be a problem with this Project. This Project is similar to many other trunk and lateral sewer system in the Metropolitan area. It is primarily a gravity system where slopes and flows are mild. Odor is not expected to be a problem at the lift station because it will be placed below grade. However, as in any sanitary sewer system, there is potential for odors to form during operation of the proposed system. Hydrogen sulfide has the potential to form in sewage material under anaerobic conditions, and can produce a rotten-egg odor, particularly where flow turbulence releases gas from solution in the wastewater. The addition of chemicals to the sanitary system to suppress growth of the odor-causing bacteria is one option if hydrogen sulfide becomes a problem in the future. Filtering air ventilated from the sewer system through a biofilter is another method of controlling odors, as is utilization of packaged carbon filtration systems.

25. Nearby resources. Are any of the following resources on or in proximity to the site? a. Archaeological, historical, or architectural resources? Yes No b. Prime or unique farmlands or land within an agricultural preserve? Yes No c. Designated parks, recreation areas, or trails? Yes No d. Scenic views and vistas? Yes No e. Other unique resources? Yes No If yes, describe the resource and identify any project-related impacts on the resources. Describe any

measures to minimize or avoid adverse impacts. Archaeological, Historical, or Architectural Resources The SHPO was contacted regarding the potential presence of cultural resources in the Project vicinity. SHPO records indicate there are no historic properties in the Project area, but that archaeological sites have been identified in the area (see Attachment 4). Based on the location information provided by SHPO, it does not appear that the archaeological sites are located near the construction corridor for the proposed sewer. Prime or Unique Farmlands, Lands within an Agricultural Preserve Several properties in the immediate Project area are zoned for agricultural use, particularly in the western part of the area. Most are designated A-1, Agricultural District, but one is designated as SA, Special Agricultural District. Much of the ultimate service area is zoned A-1, and several properties in this area are zoned SA. The intent of the SA district is to “provide for the long-term preservation of agricultural land.” The City’s comprehensive plan indicates that some of the agricultural properties will likely be developed in the future. Sanitary sewer service and other municipal utilities are being expanded to the area to allow for orderly development over the next 10 to 20 years. Infill development is anticipated in the immediate Project area as utilities become available. Several soils within the Project area have been designated as important to farming (see table in Item 19). However, as much of the land within the Project service area is planned for future urban development, areas of prime farmland soil currently in crop production will be taken out of production. Development in these areas will be subject to the comprehensive plans and zoning regulations of Dayton. Conversion of agricultural land to urban land is a consequence of population growth. Designated Parks, Recreation Areas or Trails There are parks and recreational facilities owned and operated by the City, Hennepin County (Three Rivers Park District), and the federal government (National Park Service) within the Project area.


Recreation areas include the Critical Area/MNRRA, Elm Creek Park Reserve, Cloquet Overlook Park, Donahue Dells Park, Riversbend Park, Central Park, Dayton Highlands Park, Old Orchards Park, and the Hayden Hills Golf Course (see Figure 9). A portion of the sewer alignment extends through Old Orchards Park and the Hayden Hills Golf Course. After construction, disturbed areas in the park and golf course will be restored. Portions of the alignment also extend along the boundaries of the City parks previously listed (Central Park, Donahue Dells Park, Dayton Highlands Park, and Riversbend Park). Permanent impacts to these amenities are not anticipated as the Project will be placed below grade. However, temporary indirect impacts (such as noise, dust, and general disruption caused by construction machinery) may occur to users of the facilities during construction of the Project. These impacts are expected to be short-lived and not significant. Scenic Views and Vistas Dayton River Road in the Project area has been designated as part of the State and National Scenic Byways system. It is part of the Minnesota portion of the Great River Road that extends for 575 miles from Itasca State Park to the Minnesota-Iowa border. Cloquet Overlook Park, located near the Project area features a scenic overlook. The Project will not directly impact the overlook or the park itself, but portions of the sewer will be placed within the scenic byway. As the sewer will be placed below grade, it will not permanently impact views along the byway. Construction will cause temporary impacts to users of the byway and to the road itself. After completion of construction, the road and any scenic views or vistas that might be present would be restored. Other Unique Resources Several other unique resources are present in the vicinity of the proposed Project – the Mississippi River, Diamond Creek, and Elm Creek. These resources and the means to protect them from impacts due to the Project are discussed previously under preceding EAW Items.

26. Visual impacts. Will the project create adverse visual impacts during construction or operation? Such as glare from intense lights, lights visible in wilderness areas and large visible plumes from cooling towers or exhaust stacks? Yes No If yes, explain. No visual impacts are anticipated. The sanitary sewer pipes will be placed below grade. The lift station will also be constructed below grade, and the only visible features will be a vent pipe and a seven-foot diameter concrete slab.

27. Compatibility with plans and land use regulations. Is the project subject to an adopted local comprehensive plan, land use plan or regulation, or other applicable land use, water, or resource management plan of a local, regional, state or federal agency? Yes No

If yes, describe the plan, discuss its compatibility with the project and explain how any conflicts will be resolved. If no, explain. The Project is subject to and consistent with the Dayton Comprehensive Plan, dated February 2001; the Dayton Comprehensive Sanitary Sewer Plan, dated December 2005 and approved by the MCES; and Metropolitan Council plans for sanitary sewer service. The Project will connect to the MCES Dayton-Champlin Interceptor, which is planned for construction in 2007/2008. The 1976 Metropolitan Land Planning Act requires local governments to prepare comprehensive plans and submit them to the Metropolitan Council to determine their consistency with Metropolitan system plans. The local comprehensive plan is to include a sewer element addressing the collection and disposal of wastewater generated by the community. Further, under Minn. Stat. § 473.513, local governments are


required to submit a Comprehensive Sewer Plan (CSP) describing service needs from the MCES to the Metropolitan Council for its approval. These are known as Tier II Plans. The CSP is broader in scope than the sewer element of the local comprehensive plan and provides detailed sewer system engineering information. The CSP for Dayton outlines potential alignments and sizing for city trunk sewers, as well as connection points to the Metropolitan interceptor. The immediate service area for the proposed trunk sewer includes the northeast portion of Dayton, as shown on Figure 3. Ultimately, as additional trunk lines and laterals are constructed, it will include the entire northern part of the city (also shown on Figure 3). The trunk line has been sized to accommodate anticipated growth in northeast and northwest Dayton. The City has adopted a phasing plan for the timing of extension of urban services (see Attachment 1). Future growth and land use changes will be regulated through the City’s planning and approval processes. Construction of the Project and its ultimate service area were accounted for in the design of the MCES Dayton-Champlin Interceptor.

28. Impact on infrastructure and public services. Will new or expanded utilities, roads, other infrastructure or public services be required to serve the project? Yes No If yes, describe the new or additional infrastructure or services needed. (Note: any infrastructure that is a connected action with respect to the project must be assessed in the EAW; see EAW Guidelines for details.) The Project will not cause the need for additional infrastructure itself. Future development of its service area will require additional infrastructure, although at this time, no development plans have been proposed. As development of the area progresses, other utilities and infrastructure, such as roads, collector streets, collector sewers, potable water distribution systems, storm water collection and treatment systems, schools, police, and fire protection, and other urban services will be needed to service the area. As indicated previously, City water and storm sewer is being extended to serve existing development in the immediate Project service area (northeast Dayton), in conjunction with the proposed sanitary sewer project. The road resurfacing work will be completed after the utility projects. Coordinating the timing of the service expansions will minimize the disruption to residents and businesses in the area.

29. Cumulative impacts. Minn. R. 4410.1700, subp. 7, item B requires that the RGU consider the “cumulative potential effects of related or anticipated future projects” when determining the need for an environmental impact statement. Identify any past, present or reasonably foreseeable future projects that may interact with the project described in this EAW in such a way as to cause cumulative impacts. Describe the nature of the cumulative impacts and summarize any other available information relevant to determining whether there is potential for significant environmental effects due to cumulative impacts (or discuss each cumulative impact under appropriate item(s) elsewhere on this form). As shown in the Sanitary Sewer Phasing Plan (Attachment 1), the City intends to provide sanitary sewer coverage for all of Dayton. This plan involves three discrete phases of construction over the next 20 to 30 years, and the proposed Project is the beginning of the first phase. To minimize the overall environmental impacts, construction of the proposed sanitary sewer project is being coordinated with construction of City water supply lines, storm sewer, and road improvement projects. The road work consists mainly of resurfacing to restore the road after construction of the City utilities, but in some areas the work also includes replacing culverts under the road and replacing asphalt


curbs with concrete curbs. In addition, one section of South Diamond Lake Road will be raised to address a safety concern. The projects are being coordinated so as to minimize cost, disturbance to the environment, and inconvenience to the residents and businesses in the Project area. Anticipated land use changes to future residential and commercial developments of the service area have been considered in the planning of these projects, and these changes are consistent with the City’s Comprehensive Sanitary Sewer Plan and managed population growth. Although the City is not aware of any developments being planned within the Project area at this time, the construction of the sanitary sewer project and the other City utility projects will enable future developments. The trunk sewer has been sized to accommodate long-range wastewater flows after development of the area. The trunk and lateral line placements are proposed in locations that best meet the long-term goals of the community. The potential environmental impacts from future planned development will be mitigated through enforcement of local, state, and federal ordinances and regulations. Individual development projects may be subject to environmental review and the preparation of project-specific EAWs or an Alternative Urban Areawide Review. Any sanitary sewer extensions will require a permit from the MPCA.

30. Other Potential Environmental Impacts. If the project may cause any adverse environmental impacts not addressed by items 1 to 28, identify and discuss them here, along with any proposed mitigation. Environmental impacts other than those previously discussed in this EAW are not anticipated as a result of the proposed Project.

31. Summary of issues. List any impacts and issues identified above that may require further investigation before the project is begun. Discuss any alternatives or mitigative measures that have been or may be considered for these impacts and issues, including those that have been or may be ordered as permit conditions.

The City must acquire the previously mentioned permits and approvals prior to proceeding with construction. Detailed plans and specifications must be reviewed and approved prior to construction. Issues to be addressed as identified in this EAW include:

• The City will work with the Minnesota Department of Natural Resources (DNR) to determine the ordinary high water level of DNR Public Water 27-278W and assess potential impacts. If applicable, appropriate permits from the DNR will be obtained. However, the City’s intent is to avoid impacts.

• The wetland delineation must be approved and any proposed impacts must be authorized by the local government unit prior to impacting the wetlands.

• Erosion and sediment control plans must be prepared and approved by the MPCA and the Elm Creek Watershed Management Commission prior to any construction.

• Blanding’s Turtle identification information will be provided to the contractor, as will methods to avoid or minimize impacts to the species.

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