TO: INTERESTED PARTIES · Emphasize construction, operation methods and features that will cause...

May 7, 2004 TO: INTERESTED PARTIES RE: Maple Lake/Annandale Wastewater Treatment Facility Enclosed is the Environmental Assessment Worksheet (EAW) for the proposed Maple Lake/Annandale Wastewater Treatment Facility, Wright County. The EAW was prepared by the Minnesota Pollution Control Agency (MPCA) and is being distributed for a 30-day review and comment period pursuant to the Environmental Quality Board (EQB) rules. The comment period will begin the day the EAW availability notice is published in the EQB Monitor, which will likely occur in the May 10, 2004, issue. Comments received on the EAW will be used by the MPCA in evaluating the potential for significant environmental effects from this project and deciding on the need for an Environmental Impact Statement (EIS). A final decision on the need for an EIS will be made by the MPCA Commissioner after the end of the comment period. If a request for an EIS is received during the comment period, or if the Commissioner recommends the preparation of an EIS, the MPCA Citizens’ Board (Board) will make the final decision. The final EIS need decision will also be made by the Board if so requested by the project proposer, other interested parties or MPCA staff and if this request is agreed to by one or more members of the Board or the MPCA Commissioner. The Board meets once a month, usually the fourth Tuesday of each month, at the MPCA office in St. Paul. Meetings are open to the public and interested persons may offer testimony on Board agenda items. A listing of Board members is available on request by calling (651) 296-7306. Please note that comment letters submitted to the MPCA do become public documents and will be part of the official public record for this project. If you have any questions on the EAW, please contact Dana Vanderbosch of my staff at (651) 297-1796 Sincerely, Beth G. Lockwood Supervisor, Environmental Review Unit Operations and Environmental Review Section Regional Environmental Management Division BGL:gs Enclosure

TDD (for hearing and speech impaired only): (651) 282-5332

Printed on recycled paper containing 30% fibers from paper recycled by consumers

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 the MPCA completed 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) 296-7398. 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: Maple Lake/Annandale Wastewater Treatment Facility 2. Proposer: Cities of Maple Lake & Annandale 3. RGU: Minnesota Pollution Control Agency Contact Person Brad DeWolf Contact Person Dana Vanderbosch and Title Project Manager and Title Project Manager Address 316 Southwest 4th Street Address 520 Lafayette Road North Willmar, Minnesota 56201 St. Paul, Minnesota 55155 Phone (320) 231-3956 Phone (651) 297-1796 Fax (320) 231-9710 Fax (651) 296-7782 4. Reason for EAW Preparation:

EIS Scoping

Mandatory EAW

X

CitizenPetition

RGU Discretion

Proposer Volunteered

If EAW or EIS is mandatory give EQB rule category subpart number and name: Minn. R. 4410.4300,

subp. 18(B) 5. Project Location: County Wright Township Albion Township NE 1/4 NE 1/4 Section 26 Township T120N Range R27W

Figures attached to the EAW: Figure 1. Map showing the general location of the proposed project within Wright County; Figure 2. United States Geological Survey 7.5 minute, 1:24,000 scale map indicating project boundaries; Figure 3. Site plan showing proposed locations of wastewater processes; Figure 4. Copy of the Minnesota Department of Natural Resources’ (DNR’s) Initial Natural Heritage

Database Review letter; Figure 5. Copy of the DNR’s Second Natural Heritage Database Review letter; Figure 6. Map showing sanitary sewer pipeline from Annandale and Maple Lake to the proposed facility; Figure 7. Map showing effluent pipeline from proposed facility to the North Fork of the Crow River; Figure 8. Copy of the State Historic Preservation Office (SHPO) review letter for initial project proposal;

and Figure 9. Copy of the SHPO review letter for the effluent pipeline.

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

Maple Lake/Annandale Wastewater Treatment Facility Environmental Assessment Albion Township, Minnesota 2 Worksheet

6. Description:

a. Provide a project summary of 50 words or less to be published in the EQB Monitor. The cities of Annandale and Maple Lake are proposing to regionalize wastewater treatment services by constructing a jointly operated wastewater treatment facility (WWTF) with an average wet weather (AWW) design flow of 1.18 million gallons per day (mgd). The new WWTF will be located south of Maple Lake in Albion Township in Wright County. Treated effluent will discharge to the North Fork of the Crow River.

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. Background The cities of Annandale and Maple Lake each currently operate a WWTF. The Annandale WWTF consists of a 23.4 acre primary stabilization pond and two 4.0 acre secondary ponds, all with a three-foot operating depth. Treated effluent is applied to four separate spray irrigation zones. The WWTF is designed to treat an average influent flow of 280,000 gallons per day (gpd). The Annandale WWTF is currently at capacity. The Maple Lake WWTF consists of a bar screen, grit removal, flow equalization basin, primary settling tank, high-rate trickling filter, solids contact tank with ferric chloride addition to promote the removal of phosphorus, two final clarifiers, chlorination and dechlorination, a heated anaerobic digester and a four-compartment sludge drying bed. Treated effluent discharges into the southern bay of Maple Lake. The WWTF is designed to treat an AWW design flow of 461,000 gpd. The Maple Lake WWTF is nearing design capacity. The communities in the service area are expecting to grow in the next 20 years. It is necessary for each city to expand their treatment capacity. Several options to expand wastewater treatment capacity in each city have been investigated and are briefly described in Item 31. The cities of Annandale and Maple Lake have selected the option of constructing a regional jointly operated WWTF and this project proposal is described in this EAW. Proposed Project The proposed project entails the construction of a new WWTF that will have an AWW design flow capacity of 1.18 mgd. The cities of Maple Lake and Annandale have entered into a joint powers agreement to plan, construct and operate the WWTF.

WWTF A description of the major WWTF structures and unit processes follows. All units will be placed in the southeast portion of a 35-acre parcel of land located south of Maple Lake in Albion Township:

• Lift stations – Annandale and Maple Lake:

A new lift station will be constructed in each city. Each new lift station will include two submersible pumps, a precast manhole, valve vault and monitoring station. The submersible


pumps will be sized to handle peak flows; however, the pumps could be run at slower speeds during typical operation. Diesel back-up generators in each city will ensure continued operation of the lift stations during power outages.

• Flow equalization:

The city of Maple Lake will maintain its one million gallon concrete flow equalization basin for use during high peak flow events. Excess wastewater may be diverted to this basin temporarily and then be slowly sent to the Maple Lake lift station once the storm event has ceased. The pumps for the Annandale lift station and the preliminary treatment process at the new WWTF will be designed to handle higher flows during peak events for Annandale.

• Pretreatment:

Screening A mechanical fine screen will provide removal of sticks, rags, and other large materials. These items are removed to protect subsequent process equipment. The screen will be cleaned automatically and dewatered screenings will be loaded into containers and hauled away to a solid waste disposal facility. There will also be a manually cleaned bar screen to be used when the fine screen is undergoing maintenance. Grit Removal Following screening, flow will pass through a vortex grit removal unit to remove sand, grit, and other materials which would reduce the volume of available biosolids storage and cause premature wearing of pumps and equipment if not removed.

• Biological treatment:

The new WWTF will be designed as an extended aeration activated sludge process with biological phosphorus removal. The activated sludge process is a biological treatment process whereby bacteria and other microorganisms consume organic constituents in the wastewater. Conditions in the three concrete aeration basins will be controlled for optimal growth of these organisms. The major benefit of an extended aeration process is that the longer water retention time allows for effective and efficient operation even though flows and strengths may vary widely. Additionally, this process will include an anoxic and an anaerobic zone in front of the aerated basins to promote biological phosphorus removal. Blowers and aeration equipment supply oxygen needed by the bacteria and other microorganisms that reside in the aeration basins. The aeration headers will be located in the basin while the blowers will be located in the control building.

• Back-up system for biological phosphorus removal:

Ferric chloride will be added as a chemical back-up to biological phosphorus removal. Chemical feed equipment will be installed after the aeration basins and before the final clarifiers. The chemical will attach to phosphorus in the water and precipitate out in the final clarifiers. The phosphorus is then removed with the other accumulated sludge in the final clarifiers. If the biological phosphorus removal process is removing enough phosphorus to allow the WWTF to meet the one milligram per liter (mg/L) total phosphorus effluent limit, chemical addition will not be necessary.

• Settling:

The flow of the water will be slowed in the two final clarifiers so that the microorganisms (or biomass) will settle to the bottom of the tanks while the water will flow to the disinfection unit. These solids will be removed from the final clarifiers. Some sludge will be returned to either the anaerobic, anoxic, or activated sludge basins to maintain the proper balance of microorganisms. The remaining sludge will be transferred to an aerated sludge holding tank.


The final clarifiers will be designed to meet thickening, as well as solids separation, requirements.

• Disinfection:

Disinfection of the effluent will be accomplished by the addition of chlorine. The effluent will be dechlorinated using sulfur dioxide (which neutralizes the toxicity of the chlorine) prior to discharge.

• Biosolids processing:

Sludge generated in the treatment process will be transferred to an aerated sludge holding tank where air and/or mixing will introduce oxygen to the sludge. Water separated from the sludge will be decanted and sent back to the aeration basins. The aerated sludge will be applied in thin layers to reed drying beds where the sludge will stabilize over time. Reed beds are shallow, rectangular sand beds in which aquatic reeds have been planted. The walls of the bed are constructed of reinforced concrete. After sludge has been applied to the beds, the liquid portion is strained by a sand layer and collected by underdrain pipes for treatment in the aeration basins. A polyvinyl chloride (PVC) liner is installed beneath the reed bed to insure containment of the stabilizing biosolids and of liquid passing through the beds. The operation and maintenance requirements of reed drying beds are minimal. Yearly, when the reed beds are frozen in winter, the dried reed tops sticking above the frozen beds will be removed and composted. The reed root systems lie dormant and begin to grow again once the weather warms and the beds thaw. After four to five years, the stabilized biosolids (which will contain the roots of the reed plants) will be removed from the beds. The excavated material will be tested to ensure it meets requirements set in the National Pollutant Discharge Elimination System (NPDES)/State Disposal System (SDS) Surface Water Discharge Permit and then they will be land applied on agricultural land. Land application site approvals will be obtained prior to application of biosolids. The beds will be relined and replanted with new reeds before they are put into use again. Originally, the reed beds were to be placed in a low-lying area on the north end of the proposed WWTF construction site, but seasonal high ground-water elevation would have necessitated significant filling. In addition, borings indicate the soils in the low area are classified as muck and are not suitable for construction. The new reed bed location is the south end of the proposed WWTF construction site. There will be eight reed beds with an east-west orientation. Treated effluent will travel through 3.5 miles of forcemain pipe and will discharge to the North Fork of the Crow River. A diesel back-up generator located at the proposed WWTF will ensure continued operation of treatment processes and continuous discharge of treated effluent during power outages. There will be no permitted bypasses in the collection system or at the new WWTF. Once the new WWTF begins operation, the existing Annandale and Maple Lake WWTFs will be abandoned and will no longer treat wastewater or discharge effluent. Each city will be required to submit abandonment plans for their existing WWTFs for MPCA review and approval as a condition of the new WWTF NPDES/SDS Permit for a Surface Water Discharge.


The proposed WWTF construction area appears to be clear of wetlands, but since National Wetland Inventory (NWI) data indicates that wetlands may be located on the proposed WWTF property, wetlands will be delineated in the summer of 2004. The project proposer intends to completely avoid working within wetlands if possible. Item 12 describes potential impacts to water resources in more detail. A county map showing the location of Wright County and a map showing the location of the proposed WWTF site are attached as Figures 1 and 2. Figure 3 is a preliminary site plan showing placement of the treatment processes. Annandale and Maple Lake Sanitary Sewer Pipelines The proposed WWTF will be located to the southwest of the intersection of County Highway 7 and 20th Street Northwest (NW). The proposed project includes the construction of sanitary sewer pipelines that will carry raw wastewater from Annandale and Maple Lake to the proposed WWTF. The Annandale sanitary sewer pipeline will include approximately eight miles of 12-inch forcemain pipe. The Maple Lake pipeline will include approximately four and a half miles of 10-inch forcemain pipe. The table below provides additional details regarding the pipeline:

Annandale Sanitary Sewer Pipeline Route Segment Description Length Segment 1 – South along the east side of Lundenn Drive from the lift station in Annandale to State Highway 55.

~3,000 ft

Segment 2 – Southeast along the south side of State Highway 55 to County Highway 6.

~8,500 ft

Segment 3 – South along the west side of County Highway 6 to 30th Street NW.

~18,500 ft

Segment 4 – East along the south side of 30th Street NW. ~11,000 ft Segment 5 – South along the West side of County Highway 7 and connect to the WWTF pretreatment building south of the intersection of County Highway 7 and 20th Street NW.

~6,000 ft

Maple Lake Sanitary Sewer Pipeline Route

Segment Description Length Segment 1 –South along the west side of County Highway 7 and connect to the WWTF pretreatment building south of the intersection of County Highway 7 and 20th Street NW.

~ 4.5 miles

A map showing the proposed sanitary sewer pipelines from each city to the proposed WWTF is attached as Figure 6. Effluent Pipeline Pipeline will carry treated water, or effluent, from the proposed WWTF down the western side of County Highway 7 to an outfall structure on the north bank of the North Fork of the Crow River. The effluent pipeline will include approximately 3.5 miles of 16-inch forcemain. A map showing the proposed effluent forcemain route is attached as Figure 7. The majority of areas that will be directly disturbed for installation of sewer pipe will be roadway and brush- or grass-covered road right-of-way; however the roadways are bordered in many places by wetlands and pipeline will need to cross several small streams. All pipeline corridors will be delineated prior to construction. The project will seek to avoid entirely working within wetlands; however it is possible that the project may temporarily


impact water resources during the installation of the sanitary sewer pipe and forcemain appurtenances. Potential impacts to water resources are discussed in Item 12 of this EAW. All forcemain discussed in this EAW has a 40-year design life and will be tested during construction to insure there are no leaking joints or cracked pipe. Conveyance lines are to be placed on granular bases to prevent movement or undue pressures on the lines. Forcemains will be pressure-rated PVC or ductile iron pipe. Casing will be placed in several areas along the pipeline corridors. Casing is a steel pipe which is inserted underground along the pipeline corridor; forcemain slightly smaller in diameter will run through it. The casing provides for greater structural integrity and protects the forcemain pipe within the casing. The casing also eliminates the need to open cut a highway, railroad, or county road since the casing is installed underground through a bored hole. All pipe dimensions will be finalized during plan and specification review. The project proposer intends to assure access to and from all properties located along the pipeline corridors during construction. The pipeline layout shown in Figures 6 and 7 is preliminary and portions may be slightly relocated relative to the roadways once a final design of the forcemain (all three lengths) is undertaken and detailed survey information, including onsite wetland delineation, is gathered. The goal is to minimize any environmental impact that the forcemain may cause.

Construction The construction period for the proposed project is expected to last 540 days. Construction is expected to begin in autumn of 2004, beginning with lift station improvements and forcemain installation. Typical construction hours will be limited to 7:00 a.m. to 7:00 p.m., Monday through Friday, to minimize disturbances for the surrounding area. All soils excavated during construction of the WWTF will be redistributed on the site. The soil disturbed during forcemain installation will be replaced if open trenching is used for installation. All disturbed areas will be re-vegetated. Past History A similar proposal as that described in this EAW was described in an EAW placed on public notice by the MPCA on June 23, 2003. In that proposal, treated effluent was to be discharged to an unnamed tributary of the North Fork of the Crow River. The MPCA determined that the EAW adequately addressed all environmental concerns, that an EIS was unnecessary and environmental review was concluded. In a decision made earlier this year, Wright County approved a Conditional Use Permit (CUP) on the condition that the WWTF direct discharge treated effluent to the North Fork of the Crow River. Because of this, the project proposer has submitted this EAW. The only difference between the proposed project that was described in the previous EAW and the project proposal described in this EAW is the effluent discharge route; the plan for the construction of the sanitary sewer pipelines from each city to the proposed WWTF and the plan for the construction of the treatment processes at the WWTF have not been altered.

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 WWTFs currently serving the cities of Annandale and Maple Lake are at or near design capacity. In addition, the communities in the service area are expected to grow in the coming years. The current population of the service area is 4,260. The population of the service area is expected to grow to 7,500 by the year 2024. It is necessary for each city to expand their treatment capacity and the expectation is that this proposed WWTF will provide needed wastewater treatment capacity for the service area for an estimated 20 years. The proposed WWTF will provide a higher level of treatment and provide


additional capacity to serve the anticipated future population. In addition, this proposed WWTF will provide more operational flexibility and control and will satisfy the MPCA redundancy requirements for treatment reliability. The beneficiaries will be the residents in the growing communities of Annandale and Maple Lake and other communities that may be served by this regional WWTF in the future.

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.

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 project described in this EAW is not a subsequent stage of an earlier project; however, a similar proposal was described in a previous EAW that was placed on public notice on June 23, 2003. A negative declaration on the need for an EIS was made on September 23, 2003. See the last paragraph in Item 6b for more details.

7. Project Magnitude Data Total Project Area (acres) 20 (for WWTF) or Length (miles) ~16 miles (for forcemain) Number of Residential Units: Unattached Attached maximum units per building Commercial/Industrial/Institutional Building Area (gross floor space): total square feet Indicate area of specific uses (in square feet): Office Manufacturing Retail Other Industrial Warehouse Institutional Light Industrial Agricultural Other Commercial (specify) Building height If over 2 stories, compare to heights of nearby buildings 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 United States Army Corp of

Engineers (USACOE) Section 404 Permit To be submitted, if

necessary MPCA Section 401 Water Quality Certification

of USACOE Section 404 Permit To be submitted, if necessary

MPCA NPDES/SDS Permit for a Surface Water Discharge

Submitted

MPCA Facility Plan Submitted MPCA Plans/Specifications To be submitted MPCA Sewer Extension Permit To be submitted MPCA NPDES General Stormwater Permit for

Construction Activity To be submitted


Unit of Government Type of Application Status DNR Temporary Water Appropriations

Permit (for construction dewatering) To be submitted, if necessary

DNR Public Waters Work Permit (for outfall installation)

To be submitted

DNR License for Utility Crossing of Public Lands and Waters (for laying pipe under Public Waters)

To be submitted

DNR Natural Heritage and Nongame Database Review

Completed

Minnesota Department of Transportation

Long Form Utility Permit To be submitted

Minnesota Historic Society’s SHPO

Archeological and Historical Review Completed

Wright County CUP Approved with conditions Wright County County Highway Permit To be submitted Wright County Building Permit To be submitted Public Facilities Authority State Revolving Fund Loan Preliminary approval

received

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. The proposed WWTF will be situated on a 35-acre parcel of land to the southwest of the intersection of 20th Street NW and County Highway 7 in Albion Township in Wright County. Farm fields are immediately adjacent to the south and west of the proposed site. 20th Street NW is located to the immediate north and County Highway 7 is located to the immediate east. Approximately eight homes are located within a one-mile radius of the proposed WWTF site. The Albion Ridges Golf Course is located one-fourth mile to the west of the western-most side of the plot of land on which the proposed WWTF will be situated. The aesthetics and architecture of the WWTF will be designed to fit into the surrounding area and the site will be well maintained. The property to the north and to the east of the new WWTF will be bermed and turfed/vegetated. County Highway 7 and 20th Street NW should also buffer the view of the WWTF for residents living east and north of the proposed facility. Forcemain will be installed in road rights-of-way, areas which have already been previously disturbed for the purpose of road construction. Review of MPCA databases revealed one Voluntary Investigation Cleanup site in Maple Lake and several Leaking Underground Storage Tanks located within the cities of Annandale and Maple Lake. Further review of these sites indicates that they do not lie within the proposed construction area.

There are no known environmental hazards on or within the proposed construction sites.


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 Lawn/landscaping 8.6 Wooded/forest Impervious Surfaces 1.9 Brush/grassland 52.7 49.7 Aeration basins, reed beds 2 Cropland 10 Other WWTP structures .5 TOTAL 62.7 62.7 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 in the vicinity of the proposed site primarily consists of species native to rural midwestern Minnesota. Species include deer, squirrels, rabbits, small mammals, snakes, turkeys, songbirds, amphibians, raptors, small fish and waterfowl. The site where the WWTF will be situated has been largely used for agricultural purposes and the forcemain will be installed in county road rights-of-way. The area where the WWTF will be built and where forcemain will be installed is land that has been previously disturbed. These areas are not quality wildlife habitat and the proposed project is not expected to cause significant impacts to wildlife in the area. Construction activities will affect the wildlife in the immediate vicinity of the construction site. After construction, most of the wildlife should return to their normal activities and adapt to the modified landscape. The construction projects discussed in this EAW will require NPDES General Stormwater Permits for Construction Activity. The NPDES General Stormwater Permit for Construction Activity will mitigate effects of erosion and sedimentation from construction activities to nearby receiving waters. During construction, impacts on streams and wetlands in the area will be minimized by the use of silt fences and other erosion control measures. Construction materials will be contained in limited areas before incorporation into the project and any debris generated will be regularly removed from the site for disposal. Directional drilling will be used for pipe installation near wetlands, streams and lakes to minimize impacts to those water resources. Efforts will be made to restore the land disturbed by pipe installation to its pre-construction condition as much as possible. The NPDES/SDS Permit issued to the WWTF will contain and enforce effluent limits established to protect fish, wildlife, human health and water quality. Effluent standards for the WWTF’s discharge will be re-evaluated with each NPDES/SDS Surface Water Discharge Permit reissuance, which will occur every five years.

b. Are any state (endangered or threatened) species, rare plant communities or other sensitive ecological resources such as native prairie habitat, colonial waterbird 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 20030917; ERDB 20030917-003 Describe measures to minimize or avoid adverse impacts.


The DNR’s Natural Heritage and Nongame database has been reviewed on two separate occasions to determine if any rare plant or animal species or other significant natural features are known to occur within an approximate one-mile radius of the proposed construction sites. Although the first review (which investigated the sanitary sewer pipeline routes from Annandale and Maple Lake and the proposed WWTF site) identified some occurrences of rare species, the DNR concluded that, based on the nature and location of the proposed projects, the construction of the WWTF and associated influent pipelines will not affect any known occurrences of rare features. The second review investigated the effluent pipeline route and did not identify any known occurrences of rare species or natural communities near the proposed pipeline corridor. The letters are attached as Figures 4 and 5.

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 Public Waters Inventory (PWI) number(s) if the water resources affected are on the PWI. WWTF The proposed project will require the construction of an outfall structure on the north bank of the North Fork of the Crow River where County Highway 7 intersects the river. The North Fork of the Crow River is a “public water” as determined by the DNR; watercourses are not assigned PWI numbers. The project proposer will need to obtain a Public Waters Work Permit from the DNR prior to construction of the outfall structure. As mentioned previously in this EAW, the installation of the outfall structure on the bank of the river will occur at low flow and is expected to be completed in less than one week. The excavated area will be protected with geotextile fabric and rip rap to reduce erosion. Native grass and forb seed will be planted over the rip rap. Over time, it is anticipated that the native grasses will also re-establish themselves around the rip rap and provide additional stabilization. The proposed WWTF construction area appears to be clear of wetlands, but since NWI data indicates that wetlands may be located on the general property, wetlands will be delineated prior to construction. The plan is to completely avoid working within wetlands. The proposed construction site is large enough so that WWTF structures can be moved as necessary to avoid wetland impacts.

Annandale and Maple Lake Sanitary Sewer Pipelines and Effluent Pipeline

The majority of areas that will be directly disturbed for installation of forcemain will be roadway and brush- or grass-covered road right-of-way and the construction of the pipelines will seek to avoid water resource impacts; however, the close proximity of lakes, streams and wetlands to certain portions of the proposed pipeline corridors means that potential impacts must be considered. Any pipe installation that will impact a public water will require a License for Utility Crossing of Public Lands and Waters from the DNR.

NWI data, which is maintained by the U.S. Fish and Wildlife Service, was used to compile maps for each pipeline project to make a preliminary determination of which areas along the pipeline corridors are likely to be wetlands. These maps are available as Figures 6 and 7. Since construction will occur in very close proximity to areas believed to be wetlands, delineation of wetlands will occur during the survey process to confirm the presence of wetlands identified on the NWI, and to determine if any additional wetlands are present. Figures 6 and 7 also identify the type of pipe installation method to be used. Directional drilling entails boring a horizontal tunnel using a drill bit and inserting pipe into the bored tunnel. This technique is commonly used in environmentally sensitive areas because it reduces potential for settling around the installed pipe, it minimizes the need for surface restoration and it allows the crossing of environmentally sensitive areas without disturbing the soil surface. Drilling also reduces erosion and sedimentation


potential, which will be very important where pipe will be installed near water resources. The amount of drilling indicated on Figures 6 and 7 represent the minimum to be drilled; the delineation process may indicate new water resources to avoid or the contractor may choose to bore even more of the routes for ease of construction. Open cutting entails excavating a trench, laying pipe in the trench and then backfilling with the excavated soil.

As mentioned, efforts will be made to avoid working within the wetlands while installing pipe. The pipeline corridors can be slightly relocated relative to the roadways once detailed survey information is available. If wetlands cannot be avoided, the Section 404 permit application and the Section 401 Water Quality Certification application referenced in Item 8 will be submitted. Additionally, Licenses for Utility Crossing of Public Lands and Waters from the DNR will be required for any pipe installation that impacts or crosses under water resources designated as public waters. Regardless of whether or not wetlands to be impacted are public waters, the project proposer will fully comply with the Wetland Conservation Act. Any pipeline installation that would impact a wetland would only result in the temporary disruption of that wetland. Any mitigation needed would consist solely of restoration of disturbed wetlands. There would be no net loss of wetlands. Restoration techniques may include segregation and reuse of surficial hydric soils, restoration of pre-existing grades, elimination of undesirable plant species (such as reed canary grass), and the establishment of quality wetland species through appropriate seeding or planting. The pipeline projects also entail several stream crossings, but only two of these streams have been designated as public waters. One stream runs north-south under U.S. Highway 55 to the southeast of Annandale. The second stream runs southeast of the intersection of County Highway 7 and County Highway 35. A License for Utility Crossing of Public Lands and Waters will be required for the installation of pipe underneath both of those steams. PWI maps that outline public waters can be obtained from the DNR’s Web site at the following address: http://www.dnr.state.mn.us/waters/watermgmt_section/pwi/download.html An NPDES General Stormwater Permit for Construction Activity will be obtained, as required, from the MPCA for all construction described in this EAW. As part of the permit, temporary and permanent erosion and sediment control plans will be prepared for approval by the MPCA. A drilling slurry will be used during the drilling process. The proposer will be required by the NPDES General Stormwater Permit for Construction Activity to ensure that adequate silt fencing is installed to prevent this slurry from escaping the construction site. Please refer to Item 16 for additional erosion and sedimentation 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. A well with an expected demand of 500 gallons per day for the purpose of providing drinking water and water for sanitary purposes for WWTF employees will be installed by a licensed driller. The construction will comply with well and boring statutes and rules (Minn. Stat. § 1031 and Minn. R. 4725). The sewer pipeline projects are not anticipated to impact any public or private water supply wells or other water supply systems. During construction of the pipelines, saturated subsurface conditions may be encountered, and temporary dewatering may be required. If dewatering is necessary, an evaluation of the likely volumes of water to be removed will be made and a temporary Water Appropriation Permit will be

http://www.dnr.state.mn.us/waters/watermgmt_section/pwi/download.html


obtained from the DNR, if required. All dewatering operations will be conducted in accordance with applicable DNR regulations.

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 outfall structure will be built on the north bank of the North Fork of the Crow River and it will be inside the 100-year flood plain. The project proposer will need to obtain a Public Waters Work Permit to construct the outfall structure; the DNR will determine specific conditions that must be met in order to obtain the permit. The NPDES General Stormwater Permit for Construction Activity will require the mitigation of effects of erosion and sedimentation from construction activities to the North Fork of the Crow River. The installation on the bank of the North Fork of the Crow River is expected to be completed in approximately one week and the structure will be constructed at a low flow time for the river. The excavated area will be protected with geotextile fabric and rip rap to reduce erosion. Native grass and forb seed will be planted over the rip rap. Over time, it is anticipated that the native grasses will also re-establish themselves around the rip rap and provide additional stabilization.

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.

16. Erosion and Sedimentation. Give the acreage to be graded or excavated and the cubic yards of soil to be moved: 25 acres; ~45,000 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.

General comments applicable to all construction discussed in this EAW The project proposer will be required to obtain NPDES General Stormwater Permits for Construction Activity from the MPCA to control erosion and runoff during construction. Each portion of construction (WWTF and the pipeline projects) will have its own NPDES General Stormwater Permit. This NPDES General Stormwater Permit must be obtained prior to commencing any land disturbing activities (i.e., clearing, grading, filling and excavating) at the site. The NPDES General Stormwater Permit specifically requires implementation of best management practice measures (BMPs). Construction plans will include BMPs and runoff from the construction area will be controlled by the following methods:

• scarifying only those portions of the site actively under construction; • placing silt fencing down slope of any land that is graded; • rock dam checks where necessary and • seeding and re-vegetating disturbed areas as soon as possible.

Minimizing disturbance and phasing of the proposed project along with diligent temporary stabilization of all slopes and areas of exposed soil will be necessary to prevent erosion and the discharge of sediment to state waters. The project proposer must include a site map with existing and final grades and drainage areas along with existing and final soil types and impervious surfaces on the project. WWTF Soil borings and a topographical survey indicate that none of the soils to be disturbed by construction of the proposed project are categorized as highly erodible. No steep slopes have been identified on the construction site. Seeding and mulching will provide permanent vegetative drainage and erosion control after construction. Riprap will be placed around the outfall after construction.


Annandale and Maple Lake Sanitary Sewer Pipelines and Effluent Pipeline In addition to BMPs for the site, forcemain and outfall structure, care will be taken in sensitive areas of the forcemain construction by using directional drilling to significantly reduce erosion and sedimentation potential. The material removed during excavation of trenches will be used for back filling around the installed pipe. Temporary erosion control devices may include heavy duty high-flow silt fencing, rock check dams, and storm sewer inlet protection. Seeding and mulching will provide permanent vegetative drainage and erosion control after construction.

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. General comments applicable to all construction discussed in this EAW The change in quantity and quality of site runoff before and after the construction of the proposed project will be minimal, though quality of runoff may temporarily decrease during the construction phase. Management of stormwater generated at the project sites is required. The NPDES General Stormwater Construction Activity Permit from the MPCA has specific requirements for the treatment and overall management of stormwater prior to discharge from the site. The NPDES General Stormwater Construction Activity Permit also requires that a Stormwater Pollution Prevention Plan (SWPPP) be developed to manage pollutants in stormwater runoff from the site that may occur during construction and after construction is complete. As part of the SWPPP that is developed for the site, the project proposer must include a site map with existing and final grades and drainage areas along with existing and final soil types and impervious surfaces on the project. Although it does not appear that highly erodible soils are present on the construction sites, if the preliminary site layout changes during the design phase and highly erodible soils will be disturbed the project proposer will need to note those highly erodible soils on the site map and identify what BMP's they are planning to prevent erosion or control sediment from the area. SWPPP and BMP implementation strategies must be prepared prior to submitting a permit application.

WWTF The impervious surfaces added to the area will include paved parking areas and roads. The aeration basins and the reed beds will be open basins and will make up the majority of area that will not be returned to existing grassland. These open basins do not have covers and effectively capture rainwater and snow that falls directly on them. Precipitation captured in the aeration basins will be discharged through the outfall structure with the treated effluent. Rainfall and snow captured in the reed beds will be returned to the air via evaporation and evapotranspiration. Turfed areas are not expected to be fertilized and 25-foot wide buffer strips of grassland will separate the mowed, turfed portion of the site and the unnamed, intermittent stream that flows on the western edge of the proposed WWTF site towards which stormwater runoff will flow. Runoff from impervious surfaces will flow over the surface of the ground, through the turfed area and the buffer strips, providing an opportunity for infiltration. The proposed construction site is currently cultivated with. The quality of the stormwater runoff after construction of the WWTF may improve slightly as agricultural chemicals will not be used on the site once the WWTF is operational. Annandale and Maple Lake Sanitary Sewer Pipelines and Effluent Pipeline Areas disturbed by forcemain installation will be returned as much as possible to pre-construction condition and seeded with native vegetation. The proposed pipeline projects will temporarily disturb the road right-of-way and then will return it to its original state, so the quantity and quality of the site runoff should be the same post-construction as it was pre-construction. Native vegetation will be


seeded in construction areas upon project completion. This vegetation will provide an opportunity for infiltration before road runoff flows into adjacent wetlands or streams. Increased wastewater treatment capacity will encourage development in the cities of Annandale and Maple Lake. This will result in an increase in impervious surfaces, which will result in an increase in stormwater runoff. Any construction project that disturbs over one acre of land is required to receive and comply with the terms and conditions of the NPDES General Permit for Stormwater Construction Activity, which will mitigate the effects of stormwater and erosion both during and after construction. In addition, each municipality is currently drafting a stormwater ordinance. Although it is preferable to prevent stormwater impacts to receiving waters before they occur, if stormwater runoff and erosion occur as a result of increased development these impacts can be mitigated by retroactive construction of stormwater controls, conveyances and treatment systems.

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.

WWTF Runoff from the WWTF will flow to an intermittent stream on the western edge of the proposed construction site. From there it will travel south through wetlands, southeasterly to the North Fork of the Crow River and then to the Mississippi River. There will be little impervious surface at the WWTF and what runoff rolls off the site will travel through turf and a 25-foot buffer strip providing an opportunity for infiltration before runoff will reach the unnamed stream. The proposed construction site is currently cultivated with crops. The quality of the stormwater runoff after construction of the WWTF may improve slightly as agricultural chemicals will not be used on the site once the WWTF is operational. Annandale and Maple Lake Sanitary Sewer Pipelines and Effluent Pipeline Site runoff from pipeline installation will filter through erosion control devices and either enter ground water beneath the construction area or reach the surface water bodies and various wetlands along the pipeline corridors. The pipelines will not directly affect the drainage patterns in the project area or change the volume or composition of runoff from the area. Seeding and mulching will be completed to provide permanent vegetative drainage and erosion control. While constructing in or adjacent to wetland areas, trench dewatering may be necessary; the project proposer may need to obtain a Temporary Dewatering Permit from the DNR if the amount of dewatering needed exceeds certain thresholds. Dewatering discharges will be directed upgradient of the temporary erosion controls for filtering. If dewatering discharges cannot be directed toward an


existing silt fence or hay bale structure, filter bags, or temporary sedimentation ponds will be used to contain and filter sediment from the dewatering discharge. Following construction, outfall corridor elevations and vegetation will be restored to pre-construction conditions; permanent mitigation measures should not be necessary.

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

produced or treated at the site. Wastewater created in the service area will be primarily domestic (80 percent), with some commercial/small industrial wastewater (20 percent). It is anticipated that this ratio will continue with the projected growth of the area. Commercial/small industrial wastewater will be similar in strength to domestic wastewater. There are no significant industrial users of the wastewater treatment facilities in either city at this time. If a significant industrial user moves into either city, the industry will likely be required to provide pretreatment of their wastewater prior to discharge to the wastewater collection system. At maximum capacity, it is anticipated that Annandale will contribute an AWW flow of 0.600 mgd and Maple Lake will contribute an AWW flow of 0.584 mgd. The two flows combined will equal 1.18 mgd, which will be the AWW design flow capacity of the WWTF. The following table shows the composition and quantity of the municipal wastewater to be treated at the WWTF: Composition and Quantity of Wastewater to be Treated

Parameter • Flow - Average Dry Weather, mgd 0.63 - Average Wet Weather, mgd 1.18 • Biochemical Oxygen Demand - Annual Average, pounds per day (lb/day) 1,842 • Total Suspended Solids (TSS) - Annual Average, lb/day 1,781 • Total Phosphorus - Annual Average, lb/day 45

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 proposed project will add the following components: a new pumping station and forcemain for each city to pump wastewater to the new WWTF, pretreatment equipment, aeration activated sludge basins, diffused aeration equipment, back-up phosphorus removal equipment, final clarifiers, a disinfection process, biosolids storage, reed beds, an effluent pumping station, effluent forcemain pipeline and the construction of an outfall structure on the North Fork of the Crow River. The process units are fully described in Item 6b of this EAW.

Effluent will flow through approximately 3.5 miles of forcemain and discharge to the North Fork of the Crow River. This receiving water has a Class 2B use classification per Minn. R. 7050.0222. The


full classification is 2B, 3B, 4A, 4B, 5, and 6. The quality of a Class 2B water should permit the propagation and maintenance of a healthy community of cool or warm water sport or commercial fish and their related habitat. The water should also be safe for direct body contact. The MPCA will set effluent limits that prevent the degradation of the receiving waters. The proposed project required a nondegradation for all waters review under Minn. R. 7050.0185. The MPCA has completed this review and has proposed the following effluent limits for the expanded facility’s discharge. These limits will ensure that the WWTF effluent fully complies with water quality standards set for the receiving waters:

Proposed Effluent Limitations for WWTF

Effluent Parameters Limiting Concentration or Range 5-day biochemical oxygen demand (CBOD5)

• April-November 25 mg/L

• December-March 15 mg/L

TSS 30 mg/L

Ammonia-nitrogen

• June-September 15 mg/L

• December-March 5 mg/L

Fecal coliform group organisms

• April-October 200 organisms/100 milliliters

Dissolved oxygen (DO) 6 mg/L

pH 6.0-9.0

Total residual chlorine 0.038 mg/L unless ultraviolet disinfection is used

Total phosphorus 1 mg/L, 12-month running mean

Total mercury 10 ng/L (nanograms per liter) monthly mean 17 ng/L daily maximum

Mercury The reach of the North Fork of the Crow River that stretches between Lake Koronis in Meeker County to the confluence with the South Fork of the Crow River at Greenfield in Wright County is listed on Minnesota’s 303(d) list of impaired waters for mercury. Consequently, there is a fish consumption advisory in effect for fish caught in the Crow River. To assure that the effluent from the proposed WWTF does not further degrade water quality or cause or contribute to a water quality standards violation for mercury impaired waters, an effluent limitation of 10 ηg/L is proposed. Quarterly low-level mercury monitoring will assure compliance with that limit.


DO and ammonia-nitrogen The reach of the North Fork of the Crow River that stretches between Mill Creek to the confluence with the South Fork of the Crow River is listed on Minnesota’s 303(d) list of impaired waters for low DO. For this reason, a stringent DO effluent limit has been proposed for the WWTF. The natural breaking down, or nitrification, of ammonia in water can also deplete DO in receiving waters. Limiting CBOD5 promotes nitrification during the treatment process and results in lower concentrations of ammonia-nitrogen discharged in the effluent. For this reason, stringent CBOD5 and seasonal ammonia limits have also been assigned for times of the year when DO concentrations have a tendency to be low. These limits will ensure that the WWTF will not cause or contribute to low DO in the North Fork of the Crow River.

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. N/A.

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. N/A.

19. Geologic hazards and soil conditions. a. Approximate depth (in feet) to Ground water: 13 feet minimum; >30 feet average. Bedrock: >30 feet minimum; >30 feet 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. There are no known geologic site hazards to ground water in the project area.

b. Describe the soils on the site, giving SCS classifications, if known. Discuss soil granularity and potential for groundwater contamination from wastes or chemicals spread or spilled onto the soils. Discuss any mitigation measures to prevent such contamination.

The Wright County Soil Survey indicates that the soils on the proposed WWTF construction site and on the proposed effluent pipeline route are primarily in the Lester and Glencoe series, which have a permeability range of 0.6 to 2.0 minutes per inch. The following tables provide additional soil details.

Soil Types on the Proposed WWTF Construction Site

Soil Type Permeability (inches/hour)

Gc – Glencoe silty clay loam 0.4 LcD3 – Lester clay loam, 12-18 percent slopes 0.5-2.0 LeB – Lester loam, 2-6 percent slopes 0.5-2.0 LeB2 – Lester loam, 2-6 percent slopes 0.5-2.0 LeC2 – Lester loam, 6-12 percent slopes 0.5-2.0

Soil Types along the Effluent Forcemain Corridor



A1- Alluvial Land - 0 to 6% slopes 0.3 Cw - Cordova and Webster silty clay loams - 0 to 2%

0.4-0.63

EtB - Esterville sandy loam - 2 to 6% 0.6-6.3 EtE - Esterville sandy loam - 18 to 25% 0.6-6.3 Gc - Glencoe silty clay loam - 0 to 2% 0.4 HlF - Hayden loam - 25 to 35% 0.5-2.0 LcD3 - Lester clay loam - 12 to 18% 0.5-2.0 LcE3 - Lester clay loam - 18 to 25% 0.5-2.0 LeB - Lester loam - 2 to 6% 0.5-2.0 LeB2 - Lester loam - 2 to 6% 0.5-2.0 LeC2 - Lester loam - 6 to 12% 0.5-2.0 LuA - LeSueur clay loam - 0 to 2% 0.5-2.0 LuB - LeSueur clay loam - 2 to 6% 0.5-2.0 SaE - Salida gravelly sandy loam - 12 to 35%

1.0-6.3

TeA - Terril loam occasionally flooded - 0 to 2%

0.5-2.0

WaA - Wadena loam - 0 to 2% 0.6-6.3 WaB - Wadena loam - 2 to 6% 0.6-6.3

Clay forms a protective boundary for the ground water in the WWTF construction area. The material generally has a low permeability. As a result, potential for ground-water contamination is low. There would be limited opportunity for ground-water contamination, as neither effluent nor biosolids will be spread over the WWTF property. The reed bed system will be lined with a PVC liner to contain all wastewater and biosolids. The reed bed system must also pass a leak test prior to being placed in service. Mitigative measures at the WWTF will include sealed storage tanks for chemicals used on the site and containment basins for large liquid chemical storage tanks. WWTF staff will have routine maintenance procedures to ensure the reliability of the treatment equipment and the tanks and piping will be routinely inspected for leaks. The following tables provide details on the soils adjacent to the proposed pipeline corridors:

Soil Types adjacent to the Maple Lake Sanitary Sewer Pipeline Corridor


Cw – Cordova and Webster silty clay loam 0.4-0.63 EtC2 – Esterville sandy loam, 6-12 percent slopes 0.7-6.3 Gc – Glencoe silty clay loam 0.4 HlB – Hayden loam, 2-6 percent slopes 0.3-2.0 HlC – Hayden loam, 6-12 percent slopes 0.3-2.0 HlC2 – Hayden loam, 6-12 percent slopes 0.3-2.0 LeB – Lester loam, 2-6 percent slopes 0.5-2.0 LeB2 – Lester loam, 2-6 percent slopes 0.5-2.0



LeC – Lester loam, 6-12 percent slopes LeC2 – Lester loam, 6-12 percent slopes 0.5-2.0 LtC – Lester-Esterville complex, 6-12 percent slopes 0.7-6.3 LuA – Le Sueur clay loam , 0-2 percent slopes 0.5-2.0 LuB – Le Sueur clay loam, 2-6 percent slopes 0.5-2.0 Mh - Marsh Not established Pm – Peat and muck, shallow over loam Variable

Soil Types adjacent to the Annandale Sanitary Sewer Pipeline Corridor


Ba – Beach materials, sandy Variable Bc – Biscay loam 0.5 BhB2 – Braham and Anoka fine sands, 2-6 percent slopes 6.3 BrB - Braham and Anoka loamy fine sands, 2-6 percent slopes 6.3 BuB – Burnsville sands, 0-6 percent slopes 0-6.3 BuD – Burnsville soils, 12-18 percent slopes 0-6.3 Cp – Comfrey silty clay loam 0.4-0.63 Cw – Cordova and Webster silty clay loam 0.4-0.63 Dn – Dundas silt loam 0.3-0.63 EsB – Esterville loam, 2-6 percent slopes 0.6-6.3 EsB2 - Esterville loam, 2-6 percent slopes 0.6-6.3 EtC2 – Esterville sandy loam, 6-12 percent slopes 0.7-6.3 EtD - Esterville sandy loam, 12-18 percent slopes 0.7-6.3 FaB2 – Fairhaven silt loam, 2-6 percent slopes 0.6-6.3 Gc – Glencoe silty clay loam 0.4 HlB2 – Hayden loam, 2-6 percent slopes 0.3-2.0 HlC2 – Hayden loam, 6-12 percent slopes 0.3-2.0 HlE – Hayden loam, 12-18 percent slopes 0.3-2.0 Lb – Lake borders 0.5-2.0 LcC3 - Lester clay loam, 6-12 percent slopes 0.5-2.0 LeB – Lester loam, 2-6 percent slopes 0.5-2.0 LeB2 – Lester loam, 2-6 percent slopes 0.5-2.0 LeC2 – Lester loam, 6-12 percent slopes 0.5-2.0 LtB2 – Lester-Esterville complex 0.7-6.3 LuA – Le Sueur clay loam, 0-2 percent slopes 0.5-2.0



LuB – Le Sueur clay loam, 2-6 percent slopes 0.5-2.0 Mh - Marsh Not established Pa – Peat and muck, deep Variable Pm – Peat and muck, shallow over loam Variable Ps - Peat and muck, shallow over sand Variable ScB – Salida complex, 2-6 percent slopes 1-6.3

Although the charts above identify soil types found adjacent to the proposed pipeline corridors, the right-of-way will also contain fill brought in for the purpose of road construction and roads that border wetland areas were also likely raised using larger quantities of fill. Therefore, the soils to be encountered during pipeline construction will probably be a combination of fill and native soils identified in the tables above. The entire length of all pipelines will be installed in accordance with accepted engineering practices and will be leak tested prior to use to insure there are no leaking joints or cracked pipe. Some of the pipeline will be contained in casing which will provide structural integrity and will also protect the forcemain within the casing, minimizing the potential for damage to the pipe and resulting leaks. Conveyance lines will be placed on granular bases to prevent movement or undue pressures on the lines. Forcemains will be made of pressure-rated PVC or ductile iron pipe. Ruptures in forcemain pipe are not common and typically they are more likely to occur in piping that is very old and compromised. If a leak should occur, the damaged pipe would be immediately repaired and environmental damage (if any) would be assessed. Once the extent of the environmental damage had been assessed, a plan of action to mitigate the damage would be developed.

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.

The operation of the WWTF will generate screenings, grit, and biosolids. The screenings and grit will be mechanically washed and dewatered before disposal at an approved solid waste disposal facility. As part of the treatment process, domestic sewage sludge will be produced. Sludge produced at the WWTF will be aerated in the sludge holding tank and then applied in thin layers to reed drying beds. Reed beds are shallow, rectangular sand beds in which aquatic reeds have been planted. The walls of the bed are constructed of reinforced concrete. A PVC liner is installed beneath the reed bed to insure containment of the biosolids and of liquid passing through the beds. After aerated sludge has been applied to the beds, the liquid portion is strained by the sand layer and collected by under drain pipes for recycling and treatment. The reeds assist the dewatering process.


The stabilized biosolids will be periodically removed (every four to five years) from the reed beds and land applied on approved sites. It is estimated that the amount of biosolids generated will average approximately 100,000 cubic feet per year. If all the reed bed cells are emptied in one year, the volume would be an estimated 400,000 to 500,000 cubic feet. During pipeline construction activities, several tons of construction and demolition debris will be generated through pavement removal and other construction related activities. All such demolition debris will be disposed of in accordance with Minnesota Solid Waste Rules.

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 groundwater. 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. The proposed WWTF will use chlorine gas for disinfection, sulfur dioxide for dechlorination and ferric chloride as a chemical back-up for biological phosphorus removal. The chlorine gas will be housed in a separate room in the control building with controlled access and an adequate ventilation system. The chlorine and sulfur dioxide will be contained in pressure vessels and both materials would be released as a gas to the atmosphere if the containers were to leak; leakage of these chemicals would not pose a groundwater contamination risk. The ferric chloride will be stored in above-ground tanks with secondary containment systems to hold any spillage or overflow and prevent any discharge of the materials to the ground surface.

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. The proposed WWTF will include:

• one 500 gallon ferric chloride tank 52 inches in diameter by 60 inches high; • one 150 lb sulfur dioxide pressure cylinder 10 inches in diameter and 48 inches high; • one 150 lb chlorine gas pressure cylinder 10 inches in diameter and 48 inches high; • one 500 gallon diesel oil tank; • three aeration basins with a total volume of 970,000 gallons; each basin is 30 feet by 90 feet

by 16 feet deep; • three aerated biosolids holding tanks with a total volume of 340,000; each tank is 33 feet by

33 feet by 14 feet deep and • one chlorine disinfection tank that is 47 feet high by 25 feet wide by 10 long.

All of the wastewater tanks will be tested prior to use to ensure there are no leaks. The tanks will have drain systems installed to dewater the tanks for inspection and routine maintenance. The system is designed with duplicate units for each process unit so the flow can be directed around any portion in need of maintenance without affecting treatment performance. Any emergency repairs could be carried out when a particular tank is dewatered. The 500-gallon diesel fuel storage tank will be provided with a secondary containment tank and will have an alarm system to monitor the secondary containment for leaks. See Item 20b of this EAW for information on ferric chloride, chlorine gas, and sulfur dioxide storage.


Onsite fuel storage during pipeline construction will be minimal. Typically, the general contractor will contract with a local fuel supplier to deliver diesel fuel directly the equipment. If the general contractor chooses to store fuel onsite, secondary containment will be required. The fuel tank would likely be ~1,000 gallons in size.

21. Traffic. Parking spaces added: 10 Existing spaces (if project involves expansion): Estimated total average daily traffic generated: Estimated maximum peak hour traffic generated (if known) and its timing: 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. Neither the construction phase nor the operation of the proposed WWTF will have permanent impacts on traffic in the project area. Minor, temporary traffic impacts may occur from construction vehicles traveling to and from the construction sites. Temporary lane shifts or lane closures and detours may be required during construction. The WWTF will provide parking for a maximum number of ten vehicles and will be used by employees and visitors to the site.

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. During pipeline construction, varying numbers of vehicles will be involved in excavation and construction activities. These vehicles may have short-term impacts on local air emissions, but impacts to air quality are expected to be negligible.

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. The WWTF will have a back-up 1,500 kilowatt diesel generator to supply standby power in times of electrical power outages. The generator will run as necessary to exercise the engine and to operate the WWTF during power outages. Air emissions from emergency power generation are expected to be infrequent and minor in nature.

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.)


Odors Once construction is complete, it is anticipated that some odors will be released as influent from the service area arrives in the pretreatment building. The pretreatment room will be enclosed and all ventilation from this room will be conveyed through an odor treatment system, comprised of either activated carbon columns or biofilters. The WWTF staff will monitor the existence of odors from the other treatment processes and take actions to reduce them should they occur. Any odors that may be generated outside the pretreatment building can typically be reduced by increasing the aeration rate. The sludge applied to the reed beds will be aerobically digested. The bacteria present in the reed bed biosolids may be anaerobic in the winter months due to lack of oxygen, however the area will be frozen during winter and odors will not be given off at that time. It is possible that as the ice melts in the spring the thawing beds may produce some odors; as spring progresses any odor would be expected to diminish as more oxygen becomes incorporated into the beds. Mechanical WWTFs are rarely the source of objectionable odors and the operation of the proposed WWTF is not expected to create significant nuisance odors. Noise There will be a temporary increase in noise generated by heavy machinery during the construction of the mechanical WWTF. Construction activity will be limited, as much as possible, to standard working hours to reduce noise disturbance to neighbors. The operation of the completed WWTF will not be the source of noise detectable beyond property boundaries. Dust A certain amount of dust during construction will be unavoidable and may temporarily impact residents in the vicinity of the proposed plant site and adjacent to the forcemain construction sites. Directional drilling will be used to install at least half of the forcemain and this will minimize the amount of area to be disturbed and, therefore, the amount of dust created. The contractor will be required to minimize dust from the site. Watering and leaving areas undisturbed as long as possible will likely be the primary means of dust control. Disturbed areas will be re-vegetated as soon as possible. Operation of the completed WWTF will not create dust.

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. The SHPO has been contacted twice regarding this project proposal. SHPO first reviewing the sanitary sewer pipeline routes from the cities of Maple Lake and Annandale and the proposed WWTF site in 2003. The SHPO recently reviewed the proposed effluent pipeline route. Their conclusion for both reviews is that there are no known or suspected archeological properties or properties listed on the National or State Registers of Historic Places that will be affected by any portion of the proposed project. The two SHPO letters are attached as Figures 8 and 9.


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. N/A.

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 compatible with Wright County zoning. The proposed WWTF site will be located in an agricultural zone and operation of a WWTF meets agricultural zoning requirements. A CUP must be obtained from Wright County prior to construction of the WWTF. The proposed project is compatible with the city of Annandale’s and the city of Maple Lake’s respective Comprehensive Plans.

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 proposed project will not require additional infrastructure; however, the proposed WWTF improvements and the sewer pipelines will be designed to provide service to a growing population and commercial base in the service area, and it is anticipated that additional infrastructure will be necessary to support this expanded population and commercial facilities. Infrastructure will be added by each community as needed.

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). The availability of municipal utilities will encourage additional development in the service area. Development will be encouraged in accordance with current zoning and land use requirements and will comply with applicable local ordinances and state codes and regulations intended to manage, minimize or eliminate any adverse impacts. Increased development will also result in increased traffic, air pollution, stormwater runoff, and solid waste generation. As residential and commercial areas expand, the amount of farmland, open space and wildlife habitat in the area will decrease. The service area will need to regularly assess and address impacts that occur due to the secondary development. Any development that occurs on lakes, rivers, or wetlands must meet shoreland development standards and setbacks as determined by the DNR.

Increased development will result in increases in impervious surfaces and an increase in the amount of precipitation that may run off into surface waters. Any construction project that disturbs more than one acre of soil will be required to comply with the requirements and conditions set in the NPDES General


Stormwater Permit for Construction Activity, which includes implementation of BMP measures and the development of a SWPPP to manage pollutants in stormwater runoff from the site that will occur during construction and after construction is complete. The cities of Annandale and Maple Lake have been discussing the issue of stormwater control and management for some time. Last year, each city passed a motion that stated their intention to draft a stormwater ordinance based on the MPCA’s model stormwater ordinance. The MPCA’s model ordinance was under revision at that time and so each city submitted a letter to MPCA staff in 2003 pledging to adopt the MPCA’s model stormwater ordinance once the revision was complete. Since the MPCA’s model ordinance is still under revision at this time, the cities have each decided to proceed with drafting and adopting a stormwater ordinance based on previous MPCA guidance and other guidance offered by the Environmental Protection Agency. The cities of Annandale and Maple Lake are currently working on draft stormwater ordinances in small committees in preparation for introducing proposed ordinance language to their city councils. These ordinances will establish standards and specifications for conservation practices and planning activities. The cities of Annandale and Maple Lake will have a legal obligation to enforce adopted local stormwater laws. If the MPCA discovers that either community has failed to implement and enforce their stormwater laws in a manner that protects receiving water quality and quantity, the MPCA may subject them to administrative penalties including denial of future sanitary sewer extensions. The NPDES/SDS Surface Water Discharge Permit issued to the WWTF will also contain effluent limits and conditions determined to protect the use classifications of the receiving waters. Effluent standards for the WWTF’s discharge will be re-evaluated with each NPDES/SDS Surface Water Discharge Permit reissuance, which will occur every five years.

The combination of compliance with local ordinances and compliance with the NPDES General Stormwater Permit for Construction Activity for development that will occur in the reasonably foreseeable future should provide protection to nearby receiving waters. As noted in Item 17 of this EAW, if stormwater runoff and erosion occur as a result of increased development these impacts can be mitigated by retroactive construction of stormwater controls, conveyances and treatment systems if necessary.

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. N/A.

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. One issue identified in this EAW will require additional investigation:

• Wetlands will need to be delineated in all proposed construction areas before final construction plans can be made. This information will be shared with the DNR for use in the Work in Public Water Permit/Utility Crossing Permit/Temporary Dewatering Permit processes.

The cities of Annandale and Maple Lake have considered alternatives to the project described in this EAW. The following are options considered, but not selected, by the cities:

Alternatives considered for the city of Annandale


1. Purchase land and construct a new Rapid Infiltration Basin (RIB) to utilize the full, existing pond capacity. It would have a capacity of 220,000 gpd. Design life would be five years, whereupon major improvements would be needed.

2. Build a new package mechanical plant capable of treating 180,000 gpd and a 220,000 gpd RIB.

Design life of this project would be 8 to 12 years, at which point significant improvements would be required.

3. Identical to Alternative 2, except the unit processes would be designed to treat 750,000 gpd. This

system would have a 15-to-20 year design life. 4. Identical to Alternative 2, except the unit processes would be designed for 1,300,000 gpd. This

system would have a 20-plus year design life. 5. Build a new mechanical treatment plant with pretreatment, biological nutrient removal, final clarifiers,

disinfection and biosolids handling. This plant would be designed with a 20-year design life.

Alternatives considered for the city of Maple Lake Alternatives considered for the Maple Lake wastewater treatment are broken down by unit process improvements. A selection of one item from each category would create a WWTF that would serve Maple Lake for 20 years. Headworks

a. No action or b. new screening/grit removal

Biological Process

a. No action; b. new trickling filter to improve loading capacity; c. new activated sludge process on site; or d. new Sequencing Batch Reactors for biological nutrient removal.

Disinfection

a. Chlorination and dechlorination in new chlorine contact tank; or b. UV disinfection in new basins with new equipment.

Biosolids Handling

a. Haul biosolids to Hutchinson, eliminating the need for onsite sludge storage; b. construct treatment and storage. Build reed beds and convert existing digester to aerated storage

for on site treatment; or c. construct treatment and liquid storage upgrading existing equipment and storage for on site

treatment.


RGU CERTIFICATION. I hereby certify that: • The information contained in this document is accurate and complete to the best of my knowledge. • The EAW describes the complete project; there are no other projects, stages or components other than those

described in this document, which are related to the project as connected actions or phased actions, as defined at Minn. R. 4410.0200, subps. 9b and 60, respectively.

• Copies of this EAW are being sent to the entire EQB distribution list. Name and Title of Signer: Beth G. Lockwood, Supervisor, Environmental Review Unit Operations and Environmental Review Section

Regional Environmental Management Division Date:

The format of the Environmental Assessment Worksheet was prepared by the staff of the Environmental Quality Board at Minnesota Planning. For additional information, worksheets or for EAW Guidelines, contact: Environmental Quality Board, 658 Cedar St., St. Paul, MN 55155, 651-296-8253, or at their Web site http://www.mnplan.state.mn.us.

http://www.mnplan.state.mn.us

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