STATE OF MINNESOTA MINNESOTA POLLUTION CONTROL AGENCY

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2 STATE OF MINNESOTA MINNESOTA POLLUTION CONTROL AGENCY IN THE MATTER OF THE DECISION ON THE NEED FOR AN ENVIRONMENTAL IMPACT STATEMENT FOR THE PROPOSED CITY OF TRACY CONSTRUCTION OF NEW WASTEWATER TREATMENT FACILITY, MONROE TOWNSHIP, LYON COUNTY, MINNESOTA FINDINGS OF FACT CONCLUSIONS OF LAW AND ORDER Pursuant to Minn. ch. 4410, the Minnesota Pollution Control Agency (MPCA) staff prepared and distributed an Environmental Assessment Worksheet (EAW) for the city of Tracy s proposed (Proposer) construction of a new wastewater treatment facility (WWTF) (Project). Based on the MPCA staff environmental review, the EAW, comments and information received during the comment period, and other information in the record of the MPCA, the MPCA hereby makes the following,, and Order. FINDINGS OF FACT Project Description 1. The Proposer currently holds National Pollutant Discharge Elimination System/State Disposal System Permit MN (WWTF Permit) issued by the MPCA to treat domestic strength wastewater at its existing WWTF, which consists of two separate two-pond systems (North and South Systems). 2. The WWTF Permit authorizes the Proposer to seasonally discharge treated wastewater to either Discharge Outlet SD001 or Discharge Outlet SD002 into a ditch that flows northeast and eventually into the Cottonwood River. The Proposer s current design for the existing WWTF allows treatment of a design average wet weather flow (AWWF) of million gallons per day (mgd) (0.150 mgd for each two-pond system). 3. The Proposer is proposing to construct the Project as a three-cell clay-lined stabilization treatment pond system with one controlled discharge pipe that will seasonally convey treated wastewater to a new Discharge Station Outlet SD005 into an unnamed intermittent stream into Judicial Ditch 9, then on to the Cottonwood River. 4. The Proposer will use alum as part of the design in order to precipitate phosphorus out of the wastewater and settle with solids to the base of each pond. 5. The Proposer has designed the Project to treat a higher AWWF of mgd, with larger ponds, in anticipation of city growth. The Proposer s Project will replace the existing WWTF, which the Proposer will decommission after completion of the Project. Printed on recycled paper containing at least 30% fibers from paper recycled by consumers

3 6. At the same time the Proposer is constructing the Project, the Proposer will replace existing sewer and water lines within the Proposer s city boundaries as well as the existing collection system line. The Proposer will also construct and place new sewer collection pipes at the existing WWTF, connecting this new sewer collection line at the end of the existing sewer collection line, and extending the new sewer collection line to the Project in order to convey wastewater for treatment at the Project. 7. The Proposer will also make physical improvements to its water distribution system by replacing existing water distribution pipes with new pipes. The sewer and water distribution pipes are in the same areas within City boundaries, so the Proposer will excavate the areas to remove and replace both sewer and water distribution pipes concurrently to avoid opening up streets and sidewalks more than once. 8. The Proposer is required to meet Minnesota Department of Health (MDH) rules (Minn. R. pt ) requiring lateral separation distances between sewer and water distribution pipes. 9. The Proposer will also widen a stormwater culvert under U.S. Highway 14, to improve capacity for the outlet. Procedural History 10. The Proposer submitted a WWTF Permit application for the Project on January 14, Pursuant to Minn. R , subp. 18 (B), the MPCA determined the Project exceeded the mandatory EAW threshold for construction of a new WWTF. The MPCA is the Responsible Government Unit (RGU) for the EAW. 12. Pursuant to Minn. R , the EAW was distributed to the Environmental Quality Board (EQB) mailing list and other interested parties on March 20, The MPCA notified the public of the availability of the EAW for public comment. The MPCA provided a news release to media across the state, as well as other interested parties, on March 20, The notice of the availability of the EAW was published in the EQB Monitor on March 20, 2017, and the EAW was made available for review on the MPCA website at The public comment period for the EAW began on March 20, 2017, and ended on April 19, During the 30-day comment period, the MPCA received comments from the following: the U.S. Department of the Army Corps of Engineers (USACE), the Minnesota Department of Natural Resources (DNR), and the Southwest Regional Development Commission (SWRDC). The list of the commenters and their comments are included as Appendix A to these Findings. 15. The MPCA prepared written responses to the comments received during the 30-day public comment period. The responses to the comments are also included as Appendix A to these findings. 2

4 Criteria for Determining the Potential for Significant Environmental Effects 16. Under Minn. R , the MPCA must order an Environmental Impact Statement (EIS) for projects that have the potential for significant environmental effects. In deciding whether a project has the potential for significant environmental effects, the MPCA must compare the impacts that may be reasonably expected to occur from the project with the criteria set forth in Minn. R , subp. 7. The following factors shall be considered: A. Type, extent, and reversibility of environmental effects. B. Cumulative potential effects. The responsible governmental unit (RGU) shall consider the following factors: whether the cumulative potential effect is significant; whether the contribution from the project is significant when viewed in connection with other contributions to the cumulative potential effect; the degree to which the project complies with approved mitigation measures specifically designed to address the cumulative potential effect; and the efforts of the proposer to minimize the contributions from the project. C. The extent to which the environmental effects are subject to mitigation by ongoing public regulatory authority. The RGU may rely only on mitigation measures that are specific and that can be reasonably expected to effectively mitigate the identified environmental impacts of the project. D. The extent to which environmental effects can be anticipated and controlled as a result of other available environmental studies undertaken by public agencies or the project proposer, including other EISs. The MPCA Findings with Respect to Each of These Criteria Are Set Forth Below Type, Extent, and Reversibility of Environmental Effects 17. The first criterion that the MPCA must consider when determining if a project has the potential for significant environmental effects is the type, extent, and reversibility of environmental effects Minn. R , subp. 7. A. The MPCA findings with respect to this criterion are set forth below. 18. The types of impacts that may reasonably be expected to occur from the Project include the following: Surface water quality impacts related to the Project; Surface water quality impacts related to stormwater runoff; and Surface water quality impacts related to wetlands. 19. The MPCA received written comments during the comment period regarding: 3

5 The need for the Proposer to obtain a USACE permit for work installing riprap where the wastewater discharge pipe outlets to an unnamed intermittent stream and stabilizing slopes leading to the intermittent stream; and The need to identify the number of acres that will be returned to agricultural production due to the decommissioning of the existing WWTF. 20. With respect to the extent and reversibility of impacts that are reasonably expected to occur from the Project, the MPCA makes the following findings. Findings of surface water quality impacts related to the Project 21. The Proposer has applied for modification of the WWTF Permit for continued operation of the existing WWTF, and construction and operation of the Project. 22. The Proposer has submitted plans and specifications for construction of the Project. 23. The WWTF Permit regulates the discharge and pollutant loadings allowed for the existing WWTF and the Project. The WWTF Permit established load limitations to ensure that water quality standards and designated uses of the immediate and downstream receiving waters are protected. 24. The Project involves the following: a) Construction of the new three-cell clay-lined stabilization treatment pond system with a new discharge outfall to an unnamed intermittent stream; b) Replacement of existing sewer lines with city boundaries, construction of a new sewer collection line to further extend the conveyance of wastewater to the Project for treatment; c) Replacement of undersized water lines, and widen a stormwater culvert under U.S. Highway During construction of the Project, the existing WWTF will continue to discharge to a ditch that flows northeast and eventually into the Cottonwood River. 26. After completion of the Project, the Proposer will convey and treat wastewater at the new WWTF constructed as part of the Project. 27. After the Proposer s Project is completed and actively treating wastewater, the Proposer will decommission the existing WWTF in the following manner: a) removing any remaining wastewater and routing it to the Project for treatment; b) removing and disposing of biosolids in accordance with local, state and federal laws; c) removing existing infrastructure such as pipes and pumps, and either recycling or disposing of the infrastructure at an appropriately licensed landfill; d) grading the berms and remainder of the pond structures. 4

6 Project discharge impacts 28. The Proposer has designed the Project to treat the City s current and expected future wastewater flows, including treatment capabilities to meet the MPCA s WWTF Permit Project discharge limits for pollutants such as 5-day carbonaceous biochemical oxygen demand (CBOD 5), total suspended solids (TSS), total phosphorus (TP), fecal coliform, ph, dissolved oxygen (DO), total mercury, and Ammonia as (N). 29. The WWTF Permit also requires the Proposer to monitor treated discharge from the Project for dissolved and total mercury, nitrite, total Kjeldahl nitrogen, ammonia nitrate, total nitrogen, chloride, calcium (Ca), magnesium (Mg), CA and Mg Hardness as CaCO 3), specific conductance, total dissolved salts, sulfates as SO4, bicarbonates (HCO3), sodium, potassium, whole effluent toxicity (WET), and monitoring for priority pollutants. 30. The Proposer will operate the Project to comply with the WWTF Permit, federal regulations, state rules, and local requirements. 31. The MPCA does not expect the Project to exceed effluent limits; however, if the Proposer exceeds those effluent limits, or noncompliance with other WWTF Permit conditions occurs, the Proposer will take corrective actions to improve operations as required by the WWTF Permit. WWTF Permit and WWTF modifications could be short-term or addressed through the normal five-year reissuance cycle. Thus, the MPCA has determined potential impacts to surface water quality from the Project discharge temporary and reversible. 32. MPCA finds that information presented in the EAW and other information in the environmental review record is adequate to address the concerns related to surface water impacts related to Project discharge. 33. The MPCA considered impacts on surface waters that are reasonably expected to occur from the Project during the review process and determined that appropriation mitigation measures are available and will be required to prevent significant adverse impacts. Findings on surface water quality impacts related to stormwater runoff 34. The MPCA examined the potential environmental impacts associated with stormwater runoff during and after construction of the Project. The Project site is west of Lone Tree Creek, and the Project s wastewater discharge will outlet to an unnamed intermittent stream, which the U.S. Fish and Wildlife Services (USFWS) also describes as a freshwater emergent wetland. This intermittent stream subsequently connects to the Cottonwood River approximately 8.5 miles downstream. 35. The Project construction activities will not take place in Lone Tree Creek. 36. The Project construction activities include installation of stone riprap at the location of the discharge outlet to the unnamed intermittent stream. 5

7 37. The Proposer will obtain NPDES/SDS Construction Stormwater Permit (CSW Permit) coverage for the Project. 38. The CSW Permit requires the Proposer to develop and implement stormwater pollution prevention plans (SWPPP) to prevent erosion and control sediment using best management practices (BMPs) to mitigate stormwater impacts. The SWPPP contains BMPs designed specifically for the Project sites and activities to control stormwater, minimize erosion, and prevent impacts to water bodies. 39. If construction of the Project causes any stormwater-related impacts, the MPCA finds them temporary in nature and reversible since BMPs prevent long-term effects. 40. The MPCA finds that information presented in the EAW and other information in the environmental review record is sufficient to adequately address the impacts on water quality from stormwater that are reasonably expected to occur from the Project. 41. The Proposer will utilize stormwater pollution prevention methods as required by the CSW Permit to prevent significant adverse impacts. 42. The MPCA finds the proposed Project does not have the potential for significant environmental effects based on the type, extent, and reversibility of stormwater impacts reasonably expected to occur from the Project. Findings on surface water quality impacts related to wetlands 43. The Proposer completed a wetland delineation for the Project, using available background information including aerial photographs, USFSW National Wetland Inventory (NWI) maps, DNR Public Waters Inventory (PWI) maps, a United State Geological Services (USGS) topographic map, and Lyon County Soil Survey maps. 44. The Proposer also conducted fieldwork at the Project site and identified two wetlands next to the north side of the Project site. 45. The MPCA evaluated the Project, including a review of the Project area on the USFWS area mapper. The Project is in an area the USFWS describes as a Riverine System. The Riverine System includes four Subsystems. The Subsystem that applies here is the Intermittent Subsystem. Characteristics of this subsystem include flowing water for only part of the year; the Subsystem contains a streambed and is subject to seasonal flooding. DNR has not listed the riverine at this location as a protected water body, such as a protected wetland. The MPCA believes the riverine is a grassed waterway that may have been put in place a number of years ago to drain farmland to the Proposer-identified wetland areas. 46. The Proposer has designed the Project to avoid the identified wetlands west of the Project site, and comply with the Federal Clean Water Act and the Minnesota Wetland Conservation Act. 47. The Proposer had indicated it would send final completed Project construction/grading plans to the USACE to document that no wetland impacts will result from Project construction. 6

8 48. The MPCA has recommended the Proposer contact the USACE in advance of completing Project construction/grading plans in order to determine all that it has complied with all USACE-required permit/approval submittals. 49. The MPCA finds the information presented in the EAW and other information in the environmental review record, including responses to comments, is sufficient to adequately assess the impacts on water quality of wetlands that are reasonably expected to occur from the Project. 50. The MPCA finds that the Project, as proposed, does not have the potential for significant environmental effects based on the type, extent, and reversibility of impacts related to surface water impacts on wetlands that are reasonably expected to occur from the Project. Cumulative Potential Effects 51. The second criterion that the MPCA must consider when determining if a project has the potential for significant environmental effects is the cumulative potential effects. In making this determination, the MPCA must consider whether the cumulative potential effect is significant; whether the contribution from the project is significant when viewed in connection with other contributions to the cumulative potential effect; the degree to which the project complies with approved mitigation measures specifically designed to address the cumulative potential effects; and the efforts of the proposer to minimize the contributions from the project. Minn. R subp.7.b. The MPCA findings with respect to this criterion are set forth below. 52. The EAW, public comments, and MPCA follow-up evaluation did not disclose any related or anticipated future projects that may interact with this Project in such a way as to result in significant cumulative potential environmental effects. 53. The EAW addressed the following areas for cumulative potential effects for the proposed project. Surface water quality 54. When developing effluent discharge limits for the WWTF Permit, the MPCA must consider the cumulative sources and impacts of pollutants to receiving waters to ensure that the proposed discharge does not cause or contribute to a violation of water quality standards. 55. The Proposer s existing WWTF currently discharges to a ditch that flows northeast and eventually into the Cottonwood River. The Cottonwood River flows to the Mississippi River, the Minnesota River, on to Mississippi River at a lower reach, then on to Lake Pepin. 56. The Project includes construction of a new three cell clay-lined stabilization pond WWTF and new discharge outfall to an unnamed intermittent stream that flows to Judicial Ditch 9, then on to the Mississippi River, the Minnesota River, on to a Mississippi River at a lower reach, then on to Pepin Lake. 7

9 57. Once the Proposer has completed construction and initiated operation of the Project, the Proposer will properly close the existing WWTF in accordance with applicable rules and WWTF Permit conditions, and eliminate the controlled discharge from the existing WWTF. 58. MPCA has not listed the unnamed intermittent stream, Judicial Ditch, or Wabasha Creek for Impairments. 59. MPCA has listed the Cottonwood River as impaired for: Turbidity The MPCA addresses this impairment to the Cottonwood River below. 60. Turbidity Cottonwood River. The MPCA has included the turbidity impairment in the draft Minnesota River Turbidity Total Maximum Daily Load (TMDL). The MPCA has developed a draft Waste Load Allocation (WLA) for this discharge. 61. The MPCA s draft Minnesota River Turbidity TMDL states that most WWTF permits in the Minnesota River Basin contain TSS limits of 30 or 45 milligrams per liter (mg/l), which are below the lowest surrogate of 50 mg/l used in computing TMDLs and therefore these limits help to attain and maintain the turbidity water quality standard. 62. The MPCA s WWTF Permit for the Project includes the proposed mass limit of kilograms (kg) per day TSS (design flow of mgd with a secondary pond size of 16 acres, and concentration limit of 45 mg/l; calculation of 16 acres x x 3.78 x 45 mg/l). The Project, once constructed, will treat wastewater to meet the concentration limit of 45 mg/l, lower than the lowest surrogate of 50 mg/l. 63. MPCA has listed the Cottonwood River as impaired for: Fecal Coliform The MPCA addresses this impairment to the Cottonwood River below. 64. Fecal Coliform Cottonwood River. The MPCA has a Cottonwood River Fecal Coliform TMDL that the U.S. Environmental Protection Agency (EPA) approved in The MPCA has developed a WLA for this discharge. 65. The EPA-approved TMDL states that as long as the Project discharges are at or below the permitted limit of 200 organisms per 100 milliliter (ml), the Project will not cause violations of the water quality standard. 66. MPCA has listed the Cottonwood River as impaired for: Mercury in fish tissue The MPCA addresses this impairment to the Cottonwood River below. 8

10 67. Mercury Cottonwood River. The MPCA is requiring the Proposer to conduct mercury monitoring (dissolved mercury, TSS and total mercury) of the wastewater influent, and the treated wastewater effluent prior to discharge to the unnamed intermittent stream. The MPCA requires this in accordance with the MPCA s statewide Mercury Permitting Strategy, to ensure the MPCA can track mercury, including its sources, in accordance with MPCA s statewide Mercury Permitting Strategy. The MPCA does not expect the Project to contribute to the mercury impairment in the Cottonwood River. 68. MPCA has listed the Minnesota River as impaired for: Dissolved oxygen The MPCA addresses this impairment to the Cottonwood River below. 69. Dissolved Oxygen Minnesota River. The MPCA has developed, and the EPA approved, the Lower Minnesota River Low Dissolved Oxygen TMDL. 70. The MPCA has developed the proposed annual mass phosphorus limit, as a water quality based effluent limit (WQBEL) for Lake Pepin. In accordance with MPCA phosphorus requirements, new controlled discharge stabilization ponds that discharge to the Minnesota River (directly or via tributaries) downstream of the outlet of Lac Qui Parle Reservoir and upstream of the city of Shakopee must be designed and constructed so that: a) There is no discharge of wastewater from June 1 through September 30 of each year; b) The Proposer must monitor for phosphorus; c) The Proposer must develop a phosphorus management plan; and d) The Project will avoid a discharge during the summer months. For these reasons, therefore, the MPCA considers the Project will not contribute to an exceedance of river eutrophication standards in the Minnesota River, or to the lower Minnesota low flow dissolved oxygen TMDL. 71. The Minnesota River is impaired for: Mercury in fish tissue Mercury in the water column The MPCA addresses these impairments to the Mississippi River below. 72. Mercury in fish tissue and the water column Minnesota River. The MPCA is requiring the City to conduct mercury monitoring of the influent and the Project s treated wastewater discharge, as stated in Finding 67. For the reasons in Finding 67, the MPCA expects the Project will not contribute to the mercury fish tissue impairment in the Minnesota River. 73. The Minnesota River is impaired for: Fecal coliform The MPCA addresses this impairment to the Minnesota River below. 9

11 74. Fecal coliform Minnesota River. The MPCA has not begun a TMDL for the fecal coliform impairment. The MPCA is proposing a fecal coliform effluent limit for the Project equivalent to the existing WWTF limit; this is a state discharge restriction. The Project will not result in an increased discharge of fecal coliform. 75. The Minnesota River is impaired for: Turbidity The MPCA addresses this impairment to the Minnesota River below. 76. Turbidity Minnesota River. Five of the impaired reaches are included in the draft Minnesota River Turbidity TMDL. A TMDL has not been started on four of the impaired reaches. One impaired reach is included in the South Metro Mississippi TMDL turbidity impairment. 77. The MPCA WWTF Permit for the Project requires the Project to meet a 45 mg/l TSS calendar month average limit, which is more restrictive than the TSS concentration of 50 mg/l, established as a surrogate for 25 Nephelometric Turbidity Units Turbidity WQ Standard. The MPCA has adopted Minnesota River eutrophication standards that have replaced the turbidity standard with new, regionally based standards for TSS. The authorized Project discharge of TSS will not result in an increase in the turbidity impairment for the Minnesota River. 78. The Minnesota River is impaired for: Polychlorinated biphenyls (PCBs) in fish tissue PCBs in the water column The MPCA addresses these impairments to the Mississippi River below. 79. PCBs in fish tissue and water column Minnesota River. The MPCA has no TMDLs underway for PCBs at this time. MPCA-reviewed literature suggests PCBs are legacy pollutants in that manufacturing of PCBs ceased in the United States in the late 1970s, but they persist in the environment. The MPCA believes the Project s treated wastewater will not contain PCBs as there is no contributing source (industry) to the Proposer s WWTF. For this reason, the MPCA expects the Project will not contribute to the PCB impairment in the Minnesota River. 80. The Mississippi River is impaired for: Mercury in fish tissue Mercury in the water column The MPCA addresses these impairments to the Mississippi River below. 81. Mercury in fish tissue and the water column Mississippi River. The MPCA is requiring monitoring of the influent and the Project s treated wastewater discharge, as stated in Finding 67 above. For the reasons stated in Finding 67, the MPCA does not expect the Project s treated wastewater discharge to contribute to the mercury fish tissue and water column impairment in the Mississippi River. 10

12 82. The Mississippi River is impaired for: Fecal coliform The MPCA addresses this impairment to the Mississippi River below. 83. Fecal coliform Mississippi River. The MPCA prepared and the EPA approved the Upper Mississippi River Bacterial TMDL in The MPCA did not assign a fecal coliform WLA for the Project in this TMDL. The Project is not within the TMDL area, so will not affect the TMDL area. 85. The Mississippi River is impaired for: Total suspended solids The MPCA addresses this impairment to the Mississippi River below. 86. TSS Mississippi River. The MPCA has completed a draft South Metro Mississippi River TMDL Turbidity Impairment. The MPCA has also drafted a waste WLA for the Project. 87. The MPCA s WWTF Permit for the Project includes a TSS limit of 45 mg/l calendar month average limit. For the reasons stated in Finding 77, the MPCA does not expect the Project to contribute to the TSS/turbidity impairment in the Mississippi River. 88. The Mississippi River is impaired for: PCBS in fish tissue The MPCA addresses this impairment to the Mississippi River below. 89. PCBs in fish tissue Mississippi River. For the reasons stated in Finding 79, the MPCA does not expect the Project to contribute to the PCB in fish tissue impairment in the Mississippi River. 90. The Mississippi River is impaired for: Perfluoro-octanesulfonic acid (PFOS) in fish tissue PFOS in the water column The MPCA addresses these impairments to the Mississippi River below. 91. PFOS in fish tissue and the water column Mississippi River. PFOS are extremely persistent in the environment. MPCA believes the Project s discharge does not have PFOS, as there is no contributing source (industry) to the Proposer s Project. 92. Pepin Lake is impaired for: Nutrient/eutrophication on biological indicators The MPCA addresses this impairment to the Mississippi River below. 11

13 93. Nutrient/eutrophication on biological indicators Mississippi River. The EPA approved the sitespecific standard in January The MPCA has scheduled the draft Lake Pepin-Excess Nutrients TMDL to be completed in The MPCA will incorporate the site-specific standard into Minnesota Rules when the MPCA next revises Minn. R. ch The MPCA s WWTF Permit includes the proposed annual mass phosphorus limit as a WQBEL for Lake Pepin. 95. The Mississippi River is impaired for: Mercury in fish tissue The MPCA addresses this impairment to the Mississippi River below. 96. Mercury in fish tissue Mississippi River. The MPCA is requiring monitoring of the influent and the Project s treated wastewater discharge as stated in Finding 67 above. For the reasons stated in Finding 67, the MPCA does not expect the Project s treated wastewater discharge to contribute to the mercury fish tissue impairment in the Mississippi River. 97. The Mississippi River is impaired for: PCBs in fish tissue The MPCA addresses this impairment to the Mississippi River below. 98. PCBs in fish tissue Mississippi River. For the reasons stated in Finding 79, the MPCA does not expect the Project s treated wastewater discharge to contribute to the mercury fish tissue impairment in the Mississippi River. Additional limits and monitoring requirements 99. The MPCA is requiring the Project to meet technology based limits for secondary treatment for municipal point sources, CBOD 5, and potential for hydrogen (ph) per Minn. R , subp. 1. For this reason, the MPCA does not expect the Project to allow contributions of CBOD 5, and/or ph such that either negatively impacts the immediate and downstream receiving waters The WWTF Permit also requires the Proposer to monitor treated wastewater from the Project for dissolved and total mercury, nitrite, total Kjeldahl nitrogen, ammonia nitrate, total nitrogen, chloride, calcium (Ca), magnesium (Mg) CA and MG hardness as CaCO 3), and specific conductance. This additional monitoring allows the MPCA to track information about these parameters in case of a future need to impose additional effluent limits in order to protect the receiving waters The MPCA is not aware of any related or future projects in the region that may interact with this Project in such a way to result in or contribute to any significant cumulative potential effects to surface water. 12

14 102. The MPCA determines that the Project does not have the potential for significant cumulative potential effects. The EAW, public comments, and MPCA follow-up evaluation did not disclose any related or anticipated future projects that may interact with this Project in such a way as to result in significant cumulative potential environmental effects. The Extent to Which the Environmental Effects Are Subject to Mitigation by Ongoing Public Regulatory Authority 103. The third criterion that the MPCA must consider when determining if a project has the potential for significant environmental effects is "the extent to which the environmental effects are subject to mitigation by ongoing public regulatory authority. The RGU may rely only on mitigation measures that are specific and that can be reasonably expected to effectively mitigate the identified environmental impacts of the project." Minn. R , subp. 7.C. The MPCA findings with respect to this criterion are set forth below The following permits or approvals will be required for the Project: Unit of Government MPCA MPCA MPCA Lyon County Lyon County United States Department of Agriculture Natural Resource Conservation Service Permit or Approval Required Individual WWTF Permit application for Modification/Reissuance of NPDES/SDS Permit MN Project Plans and Specifications CWS Permit Conditional Use Permit Utility Crossing Permit Farmland Conversion Impact Rating Form 105. MPCA WWTF Permit. The Proposer has applied for, and the MPCA has drafted, the WWTF Permit required for construction and operation of the Project, including the discharge of treated wastewater effluent to receiving waters. The WWTF Permit includes effluent mass and concentration pollutant limits that MPCA has developed to protect water quality in the receiving waters. The WWTF Permit also authorizes continued operation of the existing WWTF until completion and initiation of operation of the Project, and includes effluent mass and concentration for the existing WWTF that protect water quality in the receiving waters MPCA Project Plans and Specifications. The Proposer has submitted Project design plans and construction specifications to the MPCA for technical review and approval consistent with good engineering practices, WWTF Permit requirements, state rules, and federal regulations MPCA CSW Permit. The Proposer must obtain a CSW Permit since the Project disturbs more than one acre. The Proposer will prepare SWPPPs, required by the CSW Permit, detailing the BMPs the Proposer and its contractors will implement, and that will address: vehicle tracking of sediment; inspection of erosion and sediment controls; and Project construction timeframes. The CSW requires the Proposer to provide adequate temporary stormwater treatment to assure the Project runoff will not impact water quality. 13

15 108. Lyon County Conditional Use Permit. The Proposer is required to obtain all required building and conditional use permits required by local units of government to ensure compliance with local ordinances. The conditional use permit will address local zoning, environmental regulatory, and other requirements that are needed to avoid adverse effects on adjacent land uses Lyon County Utility Crossing Permit. The Proposer must apply for the Lyon County Utility Crossing Permit. This permit includes requirements to ensure the Proposer and its contractors complete the Project in accordance with applicable Lyon County ordinances and codes USDA-NRCS Farmland Conversion Impact Rating Form. The Proposer must ensure the conversion of the Project site from farmland to wastewater treatment has been assessed to ensure there are no other viable sites for the Project site, and therefore no alternative to converting prime farmland The above-listed permits include general and specific requirements for mitigation of environmental effects of the Project. The MPCA finds that the environmental effects of the Project are subject to mitigation by ongoing public regulatory authority. The Extent to Which Environmental Effects can be Anticipated and Controlled as a Result of Other Available Environmental Studies Undertaken by Public Agencies or the Project Proposer, Including Other EISs 112. The fourth criterion that the MPCA must consider is the extent to which environmental effects can be anticipated and controlled as a result of other available environmental studies undertaken by public agencies or the project proposer, including other EISs, Minn. R , subp. 7. D. The MPCA findings with respect to this criterion are set forth below MPCA staff reviewed the following documents as part of the environmental impact analysis for the proposed Project. Data presented in the EAW; WWTF Permit application; Project plans and specifications; Lyon County ordinances and zoning requirements; and Permits and environmental review of similar projects This list is not intended to be exhaustive. The MPCA also relies on information provided by the Project Proposer, persons commenting on the EAW, staff experience, and other available information obtained by staff The City s Project design and applicable regulatory authorities permit development and approval processes have addressed the environmental effects of the Project and ensure conformance with regional and local plans. The MPCA has determined there are no elements of the Project that pose the potential for significant environmental effects Based on the environmental review, previous environmental studies by public agencies or the Proposer, and staff expertise and experience on similar projects, the MPCA finds that the 14

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17 APPENDIX A Minnesota Pollution Control Agency (WWTF) Environmental Assessment Worksheet LIST OF COMMENT LETTERS RECEIVED 1. Ryan Malterud, U.S. Department of the Army, Corps of Engineers (USACE). Letter received April 5, Kevin Mixon, Minnesota Department of Natural Resources (DNR), Division of Ecological & Water Resources. Letter received April 10, Annette Fiedler, Southwest Regional Development Commission (SWRDC). Letter received April 17, RESPONSES TO COMMENTS ON THE EAW 1. Comments by Ryan Malterud, USACE. Letter received April 5, Comment 1-1: The commenter states that, based on available information, a USACE permit will be required for work associated with the proposed project to include: installing riprap to prevent erosion where the wastewater discharge pipe outlets to an unnamed intermittent stream and stabilizing slopes leading to the unnamed intermittent stream. Response: The Minnesota Pollution Control Agency (MPCA) has informed the city of Tracy (City) and the City s consultants (Nick McCabe, and Chris Larson of ISG) that the City needs to contact the USACE and set up a meeting with the USACE in order to ensure the City has obtained the USACE approvals and permits applicable to the construction of the City s new wastewater treatment facility (Project) before initiating any construction activities. 2. Comments by Kevin Mixon, DNR, Division of Ecological & Water Resources. Letter received April 10, Comment 2-1: The commenter states that the DNR has revised the EAW for the City s Project, and has no comments at this time. Response: MPCA notes the comments. 3. Comments by Annette Fiedler, SRDC. Letter received April 17, Comment 3-1: Commenter noted EAW appears to have covered each of the environmental topics. Response: MPCA notes the comments. Comment 3-2: Commenter made the following observation: The EAW identifies that 105 acres will be removed from agricultural production for the proposed new wastewater treatment facility. The entire

18 project also includes the decommissioning of the existing facility and returning it to farmland. Should the number of acres that will be returned to agricultural production also be identified. Response: The acreage of the existing WWTF and surrounding property totals 75 acres. After the existing WWTF is decommissioned, the Proposer may keep the property and have it be open farmland, use it for agricultural production, or sell it. Comment 3-3: The commenter noted the contact for the City Administrator has changed. Response: The MPCA notes the comment.

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