national pollutant discharge elimination system (npdes)/...this fact sheet has been prepared...

National Pollutant Discharge Elimination System (NPDES)/

State Disposal System (SDS) Permit Program Fact Sheet

Permit Reissuance Permittee: Southern Minnesota Beet Sugar Cooperative Facility name: Southern Minnesota Beet Sugar - Renville 83550 County Road 21

Renville, Minnesota 56284-2319 Current permit expiration date: November 30, 2009 Public comment period begins: August 18, 2020 Public comment period ends: September 17, 2020 Receiving water: Sacred Heart Creek - Class 2Bg, 3C, 4A, 4B, 5, 6 water; Beaver Creek - Class 2Bg, 3C,

4A, 4B, 5, 6 water; Beaver Creek, West Fork - Class 2Bg, 3C, 4A, 4B, 5, 6 water; County Ditch 37 (1) - Class 2Bg, 3C, 4A, 4B, 5, 6 water; Beaver Creek, East Fork - Class 2Bg, 3C, 4A, 4B, 5, 6 water; County Ditch 45 - Class 7, 3C, 4A, 4B, 5, 6 water; County Ditch 59 - Class 2Bg, 3C, 4A, 4B, 5, 6 water; Unnamed ditch - Class 7, 3C, 4A, 4B, 5, 6 water

Permitting contact: Brandon E. Smith, P.E. 520 Lafayette Road N St. Paul, MN 55155 [email protected]

Table of Contents Page

Purpose and participation ................................................................................................................................................................................... 3

Applicable statutes .............................................................................................................................................................................................. 3

Purpose .................................................................................................................................................................................................................... 3

Public participation ............................................................................................................................................................................................ 3

Facility description ................................................................................................................................................................................................. 4

Background information .................................................................................................................................................................................. 4

Facility location .................................................................................................................................................................................................... 5

Outfall location ..................................................................................................................................................................................................... 5

Map of permitted facility .................................................................................................................................................................................. 6

Components and treatment technology .................................................................................................................................................... 7

Current information ........................................................................................................................................................................................... 7

Flow schematic ..................................................................................................................................................................................................... 7

Changes to facility or operation ..................................................................................................................................................................... 7

Recent compliance history ............................................................................................................................................................................... 8

Recent monitoring history................................................................................................................................................................................ 8

Receiving water(s) ................................................................................................................................................................................................ 11

Use classification ............................................................................................................................................................................................... 11

Impairments ........................................................................................................................................................................................................ 11

Existing permit effluent limits ......................................................................................................................................................................... 11

Technology based effluent limits (TBELs) ................................................................................................................................................ 11

Water quality based effluent limits (WQBELs) ....................................................................................................................................... 11

Proposed permit effluent limits ...................................................................................................................................................................... 12

Technology based effluent limits ................................................................................................................................................................. 12

Water quality based limits ............................................................................................................................................................................. 13

Additional requirements .................................................................................................................................................................................... 15

Land Application ................................................................................................................................................................................................ 15

Pollutant Trading .............................................................................................................................................................................................. 16

Variances .............................................................................................................................................................................................................. 17

Total facility requirements ................................................................................................................................................................................ 17

Antidegradation and anti-backsliding .......................................................................................................................................................... 17

NPDES/SDS Permit Program Fact Sheet NPDES/SDS Permit MN0040665 Permit Reissuance with Modifications of 22

Purpose and participation Applicable statutes This fact sheet has been prepared according to the 40 CFR § 124.8 and 124.56 and Minn R. 7001.0100, subp. 3 in regards to a draft National Pollutant Discharge Elimination System (NPDES)/State Disposal System (SDS) permit to construct and/or operate wastewater treatment facilities and to discharge into waters of the State of Minnesota. Purpose This fact sheet outlines the principal issues related to the preparation of this draft permit and documents the decisions that were made in the determination of the effluent limitations and conditions of this permit. Public participation You may submit written comments on the terms of the draft permit or on the Commissioner’s preliminary determination. Your written comments must include the following:

1. A statement of your interest in the permit application or the draft permit. 2. A statement of the action you wish the Minnesota Pollution Control Agency (MPCA) to take,

including specific references to sections of the draft permit that you believe should be changed. 3. The reasons supporting your position, stated with sufficient specificity as to allow the Commissioner to

investigate the merits of your position. You may also request that the MPCA Commissioner hold a public informational meeting. A public informational meeting is an informal meeting which the MPCA may hold to help clarify and resolve issues. In accordance with Minn. R. 7000.0650 and Minn. R. 7001.0110, your petition requesting a public informational meeting must identify the matter of concern and must include the following: items one through three identified above; a statement of the reasons the MPCA should hold the meeting; and the issues you would like the MPCA to address at the meeting. In addition, you may submit a petition for a contested case hearing. A contested case hearing is a formal hearing before an administrative law judge. Your petition requesting a contested case hearing must include a statement of reasons or proposed findings supporting the MPCA decision to hold a contested case hearing pursuant to the criteria identified in Minn. R. 7000.1900, subp. 1 and a statement of the issues proposed to be addressed by a contested case hearing and the specific relief requested. To the extent known, your petition should include a proposed list of witnesses to be presented at the hearing, a proposed list of publications, references or studies to be introduced at the hearing, and an estimate of time required for you to present the matter at hearing. You must submit all comments, requests, and petitions during the public comment period identified on page one of this notice. All written comments, requests, and petitions received during the public comment period will be considered in the final decisions regarding the permit. If the MPCA does not receive any written comments, requests, or petitions during the public comment period, the Commissioner or other MPCA staff as authorized by the Commissioner will make the final decision concerning the draft permit. Comments, petitions, and/or requests must be submitted by the last day of the public comment period to:

Brandon E. Smith, P.E. Minnesota Pollution Control Agency 520 Lafayette Rd. N St. Paul, MN 55155


The permit will be reissued if the MPCA determines that the proposed Permittee or Permittees will, with respect to the facility or activity to be permitted, comply or undertake a schedule to achieve compliance with all applicable state and federal pollution control statutes and rules administered by the MPCA and the conditions of the permit and that all applicable requirements of Minn. Stat. ch. 116D and the rules promulgated thereunder have been fulfilled. More detail on all requirements placed on the facility may be found in the Permit document. Facility description Background information/Facility Description The principal activity at the Southern Minnesota Beet Sugar Cooperative plant is the processing of sugar beets, which are sliced and refined to produce granulated white sugar, molasses, and dried beet pulp. The permitted facilities include industrial wastewater and surface water runoff management systems at the factory site and the remote beet stockpile sites. The factory site includes beet stockpile strips, the processing factory, storage tanks, a lime storage unit, product/process area runoff controls, wastewater ponds, wastewater treatment plant and spray irrigation parcels. Facilities at the remote stockpile sites include the beet pile strips, run-on/runoff management systems and stormwater management. The principal source of water entering the process is from the sugar beets, containing approximately 70% water. If additional water is needed in the process it is supplied from groundwater wells located on parcel #3. When well water is necessary for use as boiler feed, well water reverse osmosis and ion exchange softeners are used to pre-treat the well water. Well water is also used as once through non-contact cooling water. Sanitary wastewater generated from the facility is routed to the City of Renville wastewater treatment plant. Industrial by-products generated at the facility including solids from the wastewater treatment plant are mostly beneficially used as agricultural soil amendments or cattle feed under solid waste permits SW-562 and SW-282. The wastewater treatment system consists of belt filter presses, wastewater ponds, stormwater ponds, and spray irrigation parcels. The site utilizes seven ponds for storing raw process wastewater, stormwater, and treated wastewater. The mechanical wastewater treatment plant consists of an equalization tank, heat exchangers, biogas fired heater, a conditioning tank, a high-rate up-flow fluidized bed anaerobic reactor, two aeration basins, two final clarifiers, cloth disc filters, final aeration, gravity solids thickener and anaerobic and aerobic solids storage. The wastewater treatment system treats wastewater from the beet washing process, the factory process, onsite runoff, and excess runoff water from remote pile sites. Effluent from the wastewater treatment plant may be directed to Pond #7 for holding prior to discharge. Most of the factory site surface runoff infiltrates in flat vegetated areas. Excess runoff from the factory site areas that may contain products and significant materials including runoff from pile strips, coal, coke, lime rock, lime storage unit, topsoil stockpiles are collected in stormwater ponds. Runoff from the closed portions of the lime storage unit is treated in a sedimentation basin prior to discharge from the site. Spray irrigation is used in conjunction with the wastewater treatment plant to treat and dispose of wastewater. Wastewater is pumped directly from the wastewater storage ponds and irrigated on up to ten parcels. Spray application equipment consists of center-pivot and traveling gun irrigators. Reed canary and brome grass are grown and harvested on all land application sites. Groundwater monitoring wells are used to the monitor the spray irrigation parcels and factory site facilities.


Treated process wastewaters and non-contact cooling waters may be discharged to County Ditch 45 (CD 45) via SD009 at a daily rate of up to 3.6 million gallons per day (mgd) and average daily flow rate of 2.1mgd, limited to the period September 1 through April 30. Non-contact cooling water may also be discharged to CD 37 via SD 001 at any time during the year, and during periods when non-contact cooling water is not discharged to CD 45. The SD 001 maximum daily flow rate is 0.47mgd and the average daily flow rate is 0.36mgd. Facility location The facility is located in Township 11 N, Range 36 W, Section 3; approximately 1 mile east of Renville, Minnesota on US Highway 212. Outfall location SD001 is located at 95°9'40.16"W 44°48'14.60"N, to the north of the facility in County Ditch 37. SD009 is located at 95°10'14.81"W 44°47'9.58"N, to the south of the facility in an unnamed ditch that discharges to County Ditch 45.


Map of permitted facility


Components and treatment technology Current information Same as description above. Flow schematic

Changes to facility or operation This reissuance authorizes the existing controlled discharge facility to discharge wastewater until April 30th each year; the previous permit action required discharge to cease after March 31st each year. The permit requires the facility to cease April discharges when the average temperature in the downstream Class 2 water reaches an average temperature of 13.0 degrees Celsius; this temperature was the basis for the original March 31st cutoff date, so the new condition was added to allow for better flexibility in facility operations while still being protective of the receiving water. The proposed reissuance accounts for a maximum discharge flow of 3.6 million gallons per day (MGD), compared to the previous action accounting for discharges of up to 2.3 MGD. This review was done to equate the permitted discharge flow to the existing treatment system design flow. This is intended to allow the facility greater flexibility in the controlled discharge of treated effluent as detailed in the March 2012 Design Basis Report that was submitted with the permit application. There is no increase to the design flow of the system under this permit action.


The proposed reissuance incorporates additions to the facility that were agreed to by the MPCA under a Schedule of Compliance. This includes vertical expansion of the storage volume for Ponds 5 and 6, and the addition of a wastewater pond to hold effluent from the mechanical treatment system during periods where it is not possible to discharge due to flooding or discharge diversion to meet effluent limits Pond 7E. These changes allow for better management of water in the wastewater ponds during years with high amounts of precipitation. The proposed permit authorizes discharge of stormwater generated at the factory site that has been handled using typical best management practices for the treatment and disposal of industrial runoff. Additional monitoring and reporting requirements have also been included for stormwater from beet pile sites. Additional acres have been added for spray irrigation at a new sprayfield, Parcel No. 11, represented by monitoring station LA 312. Recent compliance history A Consent Decree was executed between the MPCA, EPA, and Southern Minnesota Beet Sugar on September 26, 2016 to address past permit violations. There is no unresolved noncompliance at the facility. Recent monitoring history The table below summarizes monitoring results for SD009 for the 2019-2020 discharge season. SD001 was not used during this time.

Parameter Limit Units Apr 2019

May 2019

Jun 2019

Jul 2019

Aug 2019

Sep 2019

Oct 2019

Nov 2019

Dec 2019

Jan 2020

Feb 2020

Mar 2020

Bicarbonates (HCO3)

Avg mg/L 826 718 494 550 700 1041 622

Max mg/L 826 718 494 550 700 1041 622

BOD, 05 Day (20 Deg C)

Avg 500 kg/d 56 49.5 33.4 40.9 22.7 6.6 18.5

Max 740 kg/d 296 84.7 77.1 84.7 47.4 17.9 29.6

BOD, Carbonaceous 05 Day (20 Deg C)

Avg 15 mg/L 6 5.8 1.8 2.3 2.5 1.1 1.8

Max 34 mg/L 28 10 4.2 4.6 5 2.4 3.8

Calcium, Total (as Ca)

Avg mg/L 51.1 47.2 110 210 137 111 116

Max mg/L 51.1 47.2 110 210 137 111 116

Cations, Total Avg meq/L 23.7 18.4 15.8 19.2 17.9 17.9 21.6

Chloride, Total Avg 230 mg/L 169 117 79.9 69.3 52.8 91.7 60.8

Max 860 mg/L 214 147 164 96.7 59.3 101 62.7

Chlorine, Total Residual

Max 0.04 mg/L 0.038 0.036

Fecal Coliform, MPN or Membrane Filter 44.5C

G.Mn

200 #/100ml 4 2

Max 400 #/100ml 13 8


Flow Avg mgd 2.201 2.239 2.239 2.238 2.005 0.791 2.042

Tot Mgal 66.036

69.414

67.159

69.387

46.125

22.948

51.049

Magnesium, Total (as Mg)

Avg mg/L 54 40.7 25.3 23.6 44.8 78.9 69.1

Max mg/L 54 40.7 25.3 23.6 44.8 78.9 69.1

Mercury, Total (as Hg)

Max ng/L 0 1.02 1.35 1.11

Nitrogen, Ammonia, Total (as N)

Avg 1.4 mg/L 0.13

Avg 4.4 mg/L 0.17 0.17

Avg 7.7 mg/L 0.11 0.12 0.13 0.1

Nitrogen, Ammonia, Un-ionized (as N)

Avg mg/L 0.05 0.01 0 0 0.01 0.01 0

Max mg/L 8.44 8.75 10.27 9.21 9.8 8.61 10.1

Oxygen, Dissolved

Avg mg/L 7.47 7.08 7.4 6.71 8.1 7 6.95

Min 6 mg/L 8.3 8.3 8.2 8.1 8.1 8.25 8.2

pH Max 8.5 SU 7.8 7.91 6.74 7.42 7.5 7.73 7.95

Min 6.5 SU 2.61 4.53 26.1 1.51 0.44 0.79 1.2

Phosphorous, In Total Orthophosphate (as P)

Avg kg/d 3.73 9.54 35.55 2.37 0.59 0.9 2.1

Max kg/d 0.44 0.25 0.7 0.28 0.07 0.39 0.28

Max mg/L 0.197

0.197

0 0 0 0.26 0.162 0.244 0.226 0.197 0.213 0.207

Ave mg/L 115.68

50.35 134.96

97.28 20.48 31.52 54.25

Phosphorus, Total (as P)

Tot kg/mo 0.384

0.384

0 0 0 0.46 0.32 0.392 0.387 0.348 0.349 0.34

Ave 0.75 mg/L 115.68

166.03

301 398.27

418.75

450.3 504.52

Tot 1,135 kg/yr 155 109 74 62 94 181 148

Potassium, Total (as K)

Avg mg/L 155 109 74 62 94 181 148

Max mg/L 53.6 53.8 39.9 27.1 27.9 27.9 29.2

Sodium, % Total Cations in meq/L

Avg % 292 228 145 119 115 180 145

Sodium, Total (as Na)

Avg mg/L 1259 1020 992 1216 1012 1323 1160

Solids, Total Avg mg/L 1274 1020 992 1216 1012 1323 1160


Dissolved (TDS)

Max mg/L 10 7.1 5 11 6 4 5

Solids, Total Suspended (TSS)

Avg 30 mg/L 80 60 42 93 43 10 41

Avg 500 kg/d 18 12 7 25 10 6 7

Max 69 mg/L 152 102 59 212 85 26 59

Max 740 kg/d 1819 1578 1513 1806 1638 2150 1691

Specific Conductance, Field

Avg 3,750 umhos/cm

59.6 116 137 77.4 58.9 58.3 63.3

Sulfate, Total (as SO4)

Avg 1,000 mg/L 62 164 146 108 65.5 61.8 64.5

Max mg/L 21 18.7 14.9 17.6 17.1 23.1 16.3

Temperature, Water (C)

Avg degrees C 24.6 22.4 18.8 20.5 21.1 25.2 24.7

Max 30 degrees C 0 0 0 0

Toxicity, Whole Effluent (Acute)

Max 0.9999

TUa 6.64 5.4 4.03 5.85 2.38 1.83 3.57

Turbidity Avg 25 NTU 826 718 494 550 700 1041 622


Receiving water(s) Use classification Waters of the state are classified according to the designated uses that the associated water quality standards are intended to protect. The immediate receiving waters and downstream waters impacted by the discharges from this facility have one or more of the following classifications and associated uses.

2Bg – Uses include providing habitat for cool and warm water biota, and aquatic recreation including bathing 3C – Uses include industrial cooling and materials transport 4A – Use is for agricultural irrigation 4B – Use is as a water source for livestock and wildlife 5 – Use is for aesthetic enjoyment 6 – Other uses for which protection is reserved 7 – Aesthetic qualities and secondary body contact (limited resource value)

SD001 discharges directly to County Ditch 37 (Class 2Bg, 3C, 4A, 4B, 5, 6), which flows to West Fork Beaver Creek (Class 2Bg, 3C, 4A, 4B, 5, 6), then to Beaver Creek (Class 2Bg, 3C, 4A, 4B, 5, 6), which flows to the Minnesota River. SD009 discharges directly to an unnamed ditch (Class 7, 3C, 4A, 4B, 5, 6) that flows into County Ditch 45 (Class 7, 3C, 4A, 4B, 5, 6 water), then to Sacred Heart Creek (Class 2Bg, 3C, 4A, 4B, 5, 6), which discharges to the Minnesota River. Impairments 4 receiving waters downstream from the facility’s discharges have been identified as being impaired for one or more of their designated uses: Sacred Heart Creek, the Minnesota River, the Mississippi River, and Lake Pepin. Additional information on these impairments can be found in the Impaired Waters Review memo in attachment A to this fact sheet. Existing permit effluent limits Technology based effluent limits (TBELs) Biochemical Oxygen Demand (BOD) and Total Suspended Solids (TSS) loading limitations of 500 kg/day monthly average and 740 kg/day monthly maximum limitations were based on federal categorical standards for beet sugar processing facilities found in 40 CFR 409 Subpart A. Best Practicable Control Technology (BPT) and New Source Performance Standards (NSPS) were used to calculate these limitations. The BPT limitations are based on the original production levels for the facility established in 1975. No additional discharge loading is allowed pursuant to NSPS. The carbonaceous BOD (CBOD) limitations of 15 mg/l monthly average and 34 mg/l monthly maximum were established based on secondary treatment requirements found in Minn. R. 7050.0213 and the CBOD/ammonia relationship. The current maximum fecal coliform limitation of 400 MPN/100 mL is based on the BPT standard. Water quality based effluent limits (WQBELs) TSS concentration limitations of 30 mg/l monthly average and 69 mg/l monthly maximum are based on MN water quality standards. The average fecal coliform limit of 200 MPN/100 mL as a geometric mean is based on Minnesota Rules 7050.0222. This standard is only applicable from April 1-October 31. Given that the current permit for the facility only authorizes discharge from September through March, this limit was only applied for September-October.


The facility is authorized to use chlorine to disinfect in order to meet fecal coliform limitations. As a result, a total residual chlorine limit of 0.04 mg/L was included in order to satisfy the standard found in 7050.0222. Total ammonia is limited on a seasonal basis in the current permit, based on meeting the standard for ammonia from 7050.0222 end-of-pipe due to the 7Q10 low flow condition for the receiving water being zero. The dissolved oxygen concentration in SD009 flow must meet a minimum limitation of 6 mg/L end-of-pipe, based on the Class 2B standard in Minn. R. 7050. The allowable pH range for SD009 discharges is 6.5-8.5 SU, which is based on the most restrictive of the water quality standards applicable to the receiving waters for the discharge. The temperature of discharges from SD009 is limited to a maximum of 30 degrees Celsius, which is an interpretation of the water quality standard for Class 2B waters in Minn. R. 7050. The current permit includes a water quality-based effluent limit for turbidity of 25 NTU, based on the standard that existed at the time of permit issuance. Chloride is limited in the existing permit to average and maximum concentrations of 230 mg/L and 860 mg/L, respectively, which is an end-of-pipe application of the chronic and maximum standards for Class 2B waters. A sulfate limit of 1000 mg/L is included based on a Canadian water quality criterion for livestock watering. Specific conductance is limited as a surrogate for salinity-related parameters for which a variance was granted under the existing permit. The limit of 3750 mg/L was established based on best professional judgement following a series of whole effluent toxicity tests that were conducted to determine at what level would be protective of aquatic life and not cause acute toxicity. A limitation on whole effluent toxicity is included to further ensure that acute toxicity does not result from the facility’s discharge. The water quality standard states that the discharge must have a whole effluent toxicity test result indicating less than 1.0 acute toxicity units (TUa); this is expressed numerically as a maximum limit of 0.9999 TUa. Phosphorus is limited in the permit by both numeric limitations that restrict the amount of phosphorus that can be discharged from the facility, and by a requirement that the entire phosphorus load discharged each year be offset through point-to-nonpoint trading due to interim water quality targets to address impairments in the Minnesota River, and to mitigate potential low dissolved oxygen conditions downstream. The phosphorus concentration is limited to a hydrologic year average of 0.75 mg/L, and the total loading per hydrologic year is limited to 1135 kilograms. Proposed permit effluent limits Technology based effluent limits The proposed reissuance includes technology-based effluent limitations for 5-day biochemical oxygen demand (BOD5) and total suspended solids (TSS). These are based on effluent limitation guidelines applicable to the sugar beet processing subcategory of point sources found in federal regulations at 40 CFR 409 Subpart A. These limits are based on the facility’s production rates in 1975; per federal regulation, production expansions since promulgation of new source performance standards are subject to those requirements. For sugar beet processing facilities, new source performance standards require that there shall be no discharge of BOD5 or TSS, therefore the mass of these pollutants discharged must be capped at the amount allowed based on 1975 production rates.


A technology-based effluent limitation is also included for fecal coliform based on the BT standard found in 40 CFR 409, which is a daily maximum of 400 organisms per 100 mL of effluent. This limit is effectively a concentration-based limit, and is therefore applied end-of-pipe regardless of facility production rates. Water quality based limits Effluent limitations have been included for SD001 and SD009 for pollutants for which the MPCA has determined that the technology-based limits applicable to this facility are not sufficient to ensure that the discharge meets applicable state water quality standards. The limits and the basis for their derivation are discussed in this section. Water quality-based effluent limitations (concentration) for station SD001:

Parameter Minimum Limit Average Limit Maximum Limit Basis


N/A 15 mg/L calendar month average

34 mg/L calendar month maximum

Minn. R. 7053.0275

pH 6.5 standard units calendar month minimum

N/A 8.5 standard units calendar month maximum

7050.0222 Subp. 4, 7050.0224 Subp. 2

Temperature N/A N/A 24 degrees Celsius daily maximum

7050.0222 Subp. 4

Phosphorus 112 kg/yr 12-month moving total

7050.0150 Subp. 5; Lake Pepin TMDL


Water quality-based effluent limitations (concentration) for station SD009:

Parameter Minimum Limit Average Limit Maximum Limit Basis


N/A 15 mg/L calendar month average

34 mg/L calendar month maximum

Minn. R. 7053.0275

Chlorine, Total Residual N/A N/A 0.04 mg/L daily maximum

7050.0222 Subp. 4

Fecal Coliform, MPN or Membrane Filter 44.5C

200 calendar month geometric mean

7053.0225

Nitrogen, Ammonia, Total (as N) September, April

1.4 mg/L calendar

month average

7050.0222 Subp. 4

Nitrogen, Ammonia, Total (as N) October-November

4.4 mg/L calendar

month average

7050.0222 Subp. 4

Nitrogen, Ammonia, Total (as N) December-March

7.7 mg/L calendar

month average

7050.0222 Subp. 4

Oxygen, Dissolved 6.0 mg/L calendar month minimum

7050.0222 Subp. 4

pH 6.5 standard units calendar month minimum

N/A 8.5 standard units calendar month maximum

7050.0222 Subp. 4, 7050.0224 Subp. 2


0.75 mg/L calendar month average

7050.0150, Subp. 5


1,135 kg/yr 12-month moving total

7050.0150, Subp. 5; Lake Pepin TMDL

Temperature N/A N/A 30 degrees Celsius daily maximum

7050.0222 Subp. 4

The effluent limitations for CBOD5 are based on state secondary treatment standards, and were derived as a site-specific limitation for this facility to protect water quality based on the CBOD5/ammonia relationship. Additionally, the seasonal effluent limitation for fecal coliform is based on state secondary treatment requirements for discharge to waters of the state. Limitations for both of these parameters are included in this draft permit pursuant to anti-backsliding requirements. Water quality-based effluent limitations are included in this permit for total ammonia, dissolved oxygen, pH, phosphorus, and whole effluent toxicity. The basis for each of these limitations is detailed below. It should be noted that, except for phosphorus and the maximum pH, the water quality-based limits in this permit are based on Class 2B water quality standards. Although SD009 discharges to a water that is not classified for use as a 2B warm water fishery, these limitations are included pursuant to state and federal regulations regarding anti-backsliding and to protect downstream class 2B waters. The effluent limitations for ammonia are different for various periods within the permitted discharge window, as average conditions in the receiving water that affect ammonia toxicity are subject to seasonal variation. The limitations ensure that the chronic standard for unionized ammonia of 40 micrograms per liter will be met based on average seasonal conditions. Detailed derivation of the effluent limitations is summarized in attachment B to this fact sheet.


The effluent limitations for total residual chlorine represents application of the final acute value for this pollutant as an end-of-pipe limitation. This condition was originally added to be protective of 2B waters with no dilution capacity at low flow, to ensure that the discharge does not exceed the acute toxicity level at any point. Similarly, the effluent limitations for dissolved oxygen and temperature represent application of the 2B chronic standard as end-of-pipe limitations to ensure chronic impacts for these parameters are mitigated. The effluent limitation for phosphorus is included to be protective of downstream impaired waters which were listed as impaired prior to initial authorization of this discharge. To ensure that this facility’s discharge does not cause or contribute to downstream impairments related to phosphorus, the permit requires that the phosphorus loading from the facility’s SD009 discharge must be offset through pollutant trading. Additional detail regarding the trading requirements is included in the next section of this fact sheet. Additional requirements Special Requirements

- Permitted Discharge Management Plan. The facility is required to submit an annual report by July 1 of each year. - Biomonitoring program. The facility is required to submit an annual report in December of each year. - Dissolved Minerals (Salt) Reduction Program. The facility is required to submit an annual report by July 1 of

each year describing the dissolved mineral reduction evaluations. Land Application In addition to discharging water to the receiving waters detailed above, the facility is authorized to utilize partially treated wastewater for spray irrigation purposes. The permit authorizes land application on ten parcels near the factory location. This activity is monitored by sampling the wastewater that is land applied at these parcels, as well as monitoring groundwater impacts through sampling a network of wells surrounding the land application activities. The spray irrigation chapter in the permit has been updated to be consistent with other spray irrigation facilities.

Soil sampling stations for the irrigation sites are listed in the Appendix Section of the permit and list the required soil sampling for the irrigation sites. There are no Discharge Monitoring Reports for these stations; however, the information gathered for these soil sampling stations will be used to complete the Industrial Spray Irrigation Annual Report February 1 of each year following permit issuance.

Limit and monitoring requirements for groundwater are assigned in order to ascertain their impact on land treatment/discharge sites and downgradient groundwater quality. Requirements are based on MPCA sampling policies and/or state health requirements.

Groundwater monitoring and intervention limits are included with this permit. Intervention limits for parameters of concern are set at ¼ of the Health Risk Limit established for drinking water. Analytes and any associated intervention limits can be seen in the Limits and Monitoring Requirements portion of the permit.

The tile line discharge from the spray irrigation system have been decommissioned since the last permit.

Required submittals:

- Sprayfield Management Plan: due 60 days after permit issuance. This is required to be updated and resubmitted with the permit.

- Annual Report: Due February 1 of each year.


Pond System A pond performance evaluation and certification is due by 180 days after permit issuance. See the Industrial Pond Chapter for more information. Stormwater On April 1, 2020, the Industrial Stormwater General Permit (MNR050000) was reissued. This permit addresses stormwater discharges associated with industrial activity for facilities that discharge stormwater to waters of the state. For both industrial and municipal wastewater treatment facilities, in lieu of obtaining coverage under both the General Permit and the individual NPDES permit, the MPCA has added the necessary industrial stormwater requirements language and limits and monitoring to this permit so that coverage under this NPDES permit alone will cover both permits. This Facility has applied for and obtained a Certification of No Exposure; therefore, this permit includes language regarding the No Exposure exclusion. An annual report is due March 31 of each year for the facility/factory Stormwater (Sector U) and for the beet storage piles. These are two separate annual reports. Whole Effluent Toxicity Testing The SD 009 monitoring for whole effluent toxicity is required for salty wastewater dischargers and is set at an annual basis to assess the unknown potential toxicity of the aggregate level effects of the major ions and chemical additive substances that may be present in outfall SD 009. This data is no longer submitted on a DMR. This should be submitted in accordance with the permit. This permit includes a limit for whole effluent toxicity due to past data indicating reasonable potential to exceed 0.9999 TUa. The permittee completed a Toxicity Reduction Evaluation, which indicated that potassium may be a contributor to whole effluent toxicity. As a result, this permit also includes an intervention limit for potassium, exceedance of which requires additional toxicity testing to be completed. Mercury Monitoring This permit contains requirements for mercury monitoring. These requirements were added in response to the U.S. Environmental Protection Agency’s (EPA’s) approval of the Minnesota statewide Mercury Total Maximum Daily Load (TMDL) plan. More information on the TMDL can be found on the MPCA internet site at http://www.pca.state.mn.us/water/statewide-mercury-reduction-plan. Specific mercury monitoring requirements are found in the Waste Stream Stations and/or Surface Discharge Stations chapters of this permit. Those requirements include sampling for TSS via a grab sample taken at the same time as the total and dissolved mercury grab samples are taken. The mercury monitoring at outfall SD 009 is consistent with the MPCA “Permitting Strategy for Addressing Mercury in Municipal and Industrial Wastewater Permits” (2013). Pollutant Trading As described in the water quality-based effluent limitations section of this fact sheet, the facility is required to offset impacts to downstream receiving waters from the phosphorus contained in discharges from SD009. Based on the limits for average concentration and the facility’s design flows, the facility is required to offset a total of 1135 kilograms of total phosphorus each year.


Variances This permit includes variances from water quality standards for bicarbonates, hardness, total dissolved solids, total salinity, and specific conductance. The MPCA has determined that variance from these standards is justified on the basis that the installation and operation of the treatment technologies necessary to meet effluent limitations based on these standards would cause undue hardship on the permittee, and would lead to widespread social and economic impacts. Variance is further justified on the grounds that natural flow conditions in the receiving water limit the designated use of the receiving water as a source for irrigation. Given that each of the pollutants for which a variance is granted under this permit are related to dissolved minerals, and the methods for reducing the quantities of each of these pollutants in the discharge are similar, it is suitable to use a surrogate parameter to represent all of these pollutants for the purpose of establishing the best attainable condition and verifying continued progress toward the standards. To this end, the permit includes an alternate effluent limitation for specific conductance of 3675 mg/L as a calendar month average, and further requires continued reductions in the concentration of these pollutants in the discharge to be made as possible through implementation of a dissolved mineral reduction program. Additional information regarding the variance is included in the “Water Quality Variance Preliminary Determination” document found as attachment C to this fact sheet. Total facility requirements The Total Facility Requirements chapter of this permit incorporates requirements for all NPDES/SDS permits that are required by Minnesota Rules and the Code of Federal Regulations. Antidegradation and anti-backsliding Changes to the facility may result in an increase in pollutant loading to surface waters or other causes of degradation to surface waters. If a change to the facility will result in a net increase in pollutant loading or other causes of degradation that exceed the maximum loading authorized through conditions specified in the existing permit, the changes to the facility are subject to antidegradation requirements found in Minn. R. 7050 to 7050.0335. The discharges authorized by this permit have undergone antidegradation review to ensure that downstream water quality is preserved. This permit authorizes an expansion to the daily discharge volume from SD009 from 2.3 MGD to 3.6 MGD, as well as authorizing the discharge to continue past the previous end of the seasonal discharge window of March 31st, and allowing discharge in the month of April under limited conditions. The permit application was submitted in 2012, before the adoption of the antidegradation standards in Minn. R. 7050. Because the permit application was submitted before the adoption of the antidegradation standards, the nondegradation in standards are directly applicable. The proposed discharge expansion is not a result of a change to the design flow of the treatment system, as the input design flow of the system is not changing; the discharge flow expansion is solely to allow a larger volume of treated effluent from the existing treatment system each day as a controlled discharge. Degradation is not expected to result from these changes to the authorization. The immediate receiving waters for SD009 are limited resource value waters with zero natural flow under low flow conditions. The increased discharge allowance will result in larger volumes of the same quality effluent that is currently authorized. The first 2B water impacted by the discharge is Sacred Heart Creek, and due to the relative low flows in this stream, the water quality of the receiving water is not anticipated to be degraded beyond the currently authorized condition. Following Sacred Heart Creek, the discharge flows to the Minnesota River, which has sufficient assimilative capacity to mitigate any degradation resulting from the changes authorized under this permit. This Permit also complies with Minn. R. 7053.0275 regarding anti-backsliding: Any point


source discharger of sewage, industrial, or other wastes for which a NPDES permit has been issued by the agency that contains effluent limits more stringent than those that would be established by Minn. R. 7053.0215 to 7053.0265 shall continue to meet the effluent limits established by the permit, unless the permittee establishes that less stringent effluent limits are allowable pursuant to federal law, under section 402(o) of the Clean Water Act, United States Code, title 33, section 1342.

Term of Permit The effective date of the permit and the permit expiration date will be determined at the time of issuance. The permit will be issued for a period of approximately five years, but will not exceed five years.


Attachment A

national pollutant discharge elimination system (npdes)/...this fact sheet has been prepared...

Documents