MS4 PART III. STORMWATER POLLUTION PREVENTION PROGRAM (SWPPP)

The permittee shall develop, implement, and enforce a SWPPP designed to reduce the discharge of pollutants from the small MS4 to the Maximum Extent Practicable (MEP), to protect water quality, and to satisfy the appropriate water quality requirements of the Clean Water Act.

If the permittee enters into a partnership for purposes of meeting SWPPP requirements, the permittee maintains legal responsibility for compliance with this permit.

Existing permittees shall revise their SWPPP developed under the Agency’s small MS4 general permit No.MNR040000 that was effective June, 1, 2006, to meet the requirements of this permit in accordance with the schedule in Appendix A, Table 2. New permittees shall develop, implement, and enforce their SWPPP in accordance with the schedule in Appendix A, Table 3. The permittee’s SWPPP shall consist of the following:

A. Regulatory Mechanism(s)

To the extent allowable under state, tribal or local law, the permittee shall develop, implement, and enforce a Regulatory Mechanism(s) to meet the terms and conditions of Part III.D.3, 4, and 5. A Regulatory Mechanism(s) for the purposes of this permit may consist of contract language, an ordinance, permits, standards, or any other mechanism, that will be enforced by the permittee.

B. Enforcement Response Procedures (ERPs)

  1. The permittee shall develop and implement written ERPs to enforce and compel compliance with the Regulatory Mechanism(s) developed and implemented by the permittee in accordance with Part III.A.
  2. Enforcement conducted by the permittee pursuant to the ERPs shall be documented. Documentation shall include, at a minimum, the following:

a. Name of the person responsible for violating the terms and conditions of the permittee’s Regulatory Mechanism(s)

b. Date(s) and location(s) of the observed violation(s)

c. Description of the violation(s), including reference(s) to relevant Regulatory Mechanism(s)

d. Corrective action(s) (including completion schedule) issued by the permittee

e. Date(s) and type(s) of enforcement used to compel compliance (e.g., written notice, citation, stop work order, withholding of local authorizations, etc.)

f. Referrals to other regulatory organizations (if any)

g. Date(s) violation(s) resolved

C. Mapping and Inventory

1. Mapping

New permittees shall develop, and existing permittees shall update, a storm sewer system map that depicts the following:

a. The permittee’s entire small MS4 as a goal, but at a minimum, all pipes 12 inches or greater in diameter, including stormwater flow direction in those pipes

b. Outfalls, including a unique identification (ID) number assigned by the permittee, and an associated geographic coordinate

c. Structural stormwater BMPs that are part of the permittee’s small MS4

d. All receiving waters

2. Inventory (2009 Minnesota Session Law, Ch. 172. Sec. 28).

a. The permittee shall complete an inventory of:

  1. All ponds within the permittee’s jurisdiction that are constructed and operated for purposes of water quality treatment, stormwater detention, and flood control, and that are used for the collection of stormwater via constructed conveyances. Stormwater ponds do not include areas of temporary ponding, such as ponds that exist only during a construction project or short-term accumulations of water in road ditches.
  2. All wetlands and lakes, within the permittee’s jurisdiction, that collect stormwater via constructed conveyances.

b. The permittee shall complete and submit the inventory to the Agency on a form provided by the Commissioner. Each feature inventoried shall include the following information:

  1. A unique identification (ID) number assigned by the permittee
  2. A geographic coordinate
  3. Type of feature (e.g., pond, wetland, or lake). This may be determined by using best professional judgment.

D. Minimum Control Measures (MCMs)

The permittee shall incorporate the following six MCMs into the SWPPP. The permittee shall document as part of the SWPPP, a description of BMPs used for each MCM, the responsible person(s) and department(s) in charge, an implementation schedule, and measureable goals that will be used to determine the success of each BMP.

1. Public Education and Outreach

New permittees shall develop and implement, and existing permittees shall revise their current program, as necessary, and continue to implement, a public education program to distribute educational materials or equivalent outreach that informs the public of the impact stormwater discharges have on water bodies and that includes actions citizens, businesses, and other local organizations can take to reduce the discharge of pollutants to stormwater. The program shall also include:

a. Distribution of educational materials or equivalent outreach focused on:

  1. Specifically selected stormwater-related issue(s) of high priority to the permittee to be emphasized during this permit term (e.g., specific TMDL reduction targets, changing local business practices, promoting adoption of residential BMPs, lake improvements through lake associations, responsible management of pet waste, household chemicals, yard waste, deicing materials, etc.)
  2. Illicit discharge recognition and reporting illicit discharges to the permittee

b. An implementation plan that consists of the following:

  1. Target audience(s), including measurable goals for each audience
  2. Responsible Person(s) in charge of overall plan implementation
  3. Specific activities and schedules to reach measurable goals for each target audience
  4. A description of any coordination with and/or use of other stormwater education and outreach programs being conducted by other entities, if applicable
  5. Annual evaluation to measure the extent to which measurable goals for each target audience are attained

c. Documentation of the following information:

  1. A description of any specific stormwater-related issues identified by the permittee under Part III.D.1.a(1)
  2. All information required under Part III.D.1.b
  3. Any modifications made to the program as a result of the annual evaluation under Part III.D.1.b(5)
  4. Activities held, including dates, to reach measurable goals
  5. Quantities and descriptions of educational materials distributed, including dates distributed

2. Public Participation/Involvement

a. New permittees shall develop and implement, and existing permittees shall revise their current program, as necessary, and continue to implement, a Public Participation/Involvement program to solicit public input on the SWPPP. The permittee shall:

  1. Provide a minimum of one (1) opportunity annually for the public to provide input on the adequacy of the SWPPP. Public meetings can be conducted to satisfy this requirement provided appropriate local public notice requirements are followed and opportunity to review and comment on the SWPPP is provided.
  2. Provide access to the SWPPP document, Annual Reports, and other documentation that supports or describes the SWPPP (e.g., Regulatory Mechanism(s), etc.) for public review, upon request. All public data requests are subject to the Minnesota Government Data Practices Act, Minn. Stat. ch. 13.
  3. Consider public input, oral and written, submitted by the public to the permittee, regarding the SWPPP.

b. Document the following information:

  1. All relevant written input submitted by persons regarding the SWPPP
  2. All responses from the permittee to written input received regarding the SWPPP, including any modifications made to the SWPPP as a result of the written input received
  3. Date(s) and location(s) of events held for purposes of compliance with this requirement
  4. Notices provided to the public of any events scheduled to meet this requirement, including any electronic correspondence (e.g., website, e-mail distribution lists, notices, etc.)

3. Illicit Discharge Detection and Elimination (IDDE)

New permittees shall develop, implement, and enforce, and existing permittees shall revise their current program as necessary, and continue to implement and enforce, a program to detect and eliminate illicit discharges into the small MS4. The IDDE program shall consist of the following:

a. Map of the small MS4 as required by Part III.C.1.

b. Regulatory Mechanism(s) that effectively prohibits non-stormwater discharges into the small MS4, except those non-stormwater discharges authorized under Part I.B.1.

c. Incorporation of illicit discharge detection into all inspection and maintenance activities conducted under Part III.D.6.e and f. Where feasible, illicit discharge inspections shall be conducted during dry-weather conditions (e.g., periods of 72 or more hours of no precipitation).

d. Detecting and tracking the source of illicit discharges using visual inspections. The permittee may also include the use of mobile cameras, collecting and analyzing water samples, and/or other detailed inspection procedures that may be effective investigative tools.

e. Training of all field staff, in accordance with the requirements of Part III.D.6.g(2), in illicit discharge recognition (including conditions which could cause illicit discharges), and reporting illicit discharges for further investigation.

f. Identification of priority areas likely to have illicit discharges, including at a minimum, evaluating land uses associated with business/industrial activities, areas where illicit discharges have been identified in the past, and areas with storage of large quantities of significant materials that could result in an illicit discharge. Based on this evaluation, the permittee shall conduct additional illicit discharge inspections in those areas identified as having a higher likelihood for illicit discharges.

g. For timely response to known, suspected, and reported illicit discharges:

  1. Procedures for investigating, locating, and eliminating the source of illicit discharges.
  2. Procedures for responding to spills, including emergency response procedures to prevent spills from entering the small MS4. The procedures shall also include the immediate notification of the Minnesota Department of Public Safety Duty Officer at 1-800-422-0798 (toll free) or 651-649-5451 (Metro area), if the source of the illicit discharge is a spill or leak as defined in Minn. Stat. § 115.061.
  3. When the source of the illicit discharge is found, ERPs required by Part III.B (if necessary) to eliminate the illicit discharge and require any needed corrective action(s).

h. Documentation of the following information:

  1. Date(s) and location(s) of IDDE inspections conducted in accordance with Part III.D.3.c and f
  2. Reports of alleged illicit discharges received, including date(s) of the report(s), and any follow-up action(s) taken by the permittee
  3. Date(s) of discovery of all illicit discharges
  4. Identification of outfalls, or other areas, where illicit discharges have been discovered
  5. Sources (including a description and the responsible party) of illicit discharges (if known)
  6. Action(s) taken by the permittee, including date(s), to address discovered illicit discharges

4. Construction Site Stormwater Runoff Control

New permittees shall develop, implement, and enforce, and existing permittees shall revise their current program, as necessary, and continue to implement and enforce, a Construction Site Stormwater Runoff Control program that reduces pollutants in stormwater runoff to the small MS4 from construction activity with a land disturbance of greater than or equal to one acre, including projects less than one acre that are part of a larger common plan of development or sale, that occurs within the permittee’s jurisdiction. The program shall incorporate the following components:

a. Regulatory Mechanism(s)

A Regulatory Mechanism(s) that establishes requirements for erosion and sediment controls and waste controls that is at least as stringent as the Agency’s general permit to Discharge Stormwater Associated with Construction Activity No.MN R100001 (as of the effective date of this permit). The permittee’s Regulatory Mechanism(s) shall require that owners and operators of construction activity develop site plans that must be submitted to the permittee for review and approval, prior to the start of construction activity. Site plans must be kept up-to-date by the owners and operators of construction activity with regard to stormwater runoff controls. The Regulatory Mechanism(s) must require that site plans incorporate the following erosion and sediment controls and waste controls as described in the above referenced permit:

  1. BMPs to minimize erosion
  2. BMPs to minimize the discharge of sediment and other pollutants
  3. BMPs for dewatering activities
  4. Site inspections and records of rainfall events
  5. BMP maintenance
  6. Management of solid and hazardous wastes on each project site
  7. Final stabilization upon the completion of construction activity, including the use of perennial vegetative cover on all exposed soils or other equivalent means
  8. Criteria for the use of temporary sediment basins

b. Site plan review

The program shall include written procedures for site plan reviews conducted by the permittee prior to the start of construction activity, to ensure compliance with requirements of the Regulatory Mechanism(s). The site plan review procedure shall include notification to owners and operators proposing construction activity of the need to apply for and obtain coverage under the Agency’s general permit to Discharge Stormwater Associated with Construction Activity No.MN R100001.

c. Public input

The program shall include written procedures for receipt and consideration of reports of noncompliance or other stormwater related information on construction activity submitted by the public to the permittee.

d. Site inspections

The program shall include written procedures for conducting site inspections, to determine compliance with the permittee’s Regulatory Mechanism(s). The written procedures shall:

  1. Include procedures for identifying priority sites for inspection. Prioritization can be based on such parameters as topography, soil characteristics, type of receiving water(s), stage of construction, compliance history, weather conditions, or other local characteristics and issues.
  2. Identify frequency at which site inspections will be conducted
  3. Identify name(s) of individual(s) or position titles responsible for conducting site inspections
  4. Include a checklist or other written means to document site inspections when determining compliance.

e. ERPs required by Part III.B of this permit

f. Documentation of the following information:

  1. For each site plan review – The project name, location, total acreage to be disturbed, owner and operator of the proposed construction activity, and any stormwater related comments and supporting documentation used by the permittee to determine project approval or denial.
  2. For each site inspection - Inspection checklists or other written means used to document site inspections

5. Post-Construction Stormwater Management

New permittees shall develop, implement, and enforce, and existing permittees shall revise their current program, as necessary, and continue to implement and enforce, a Post-Construction Stormwater Management program that prevents or reduces water pollution after construction activity is completed, related to new development and redevelopment projects with land disturbance of greater than or equal to one acre, including projects less than one acre that are part of a larger common plan of development or sale, within the permittee’s jurisdiction and that discharge to the permittee’s small MS4. The program shall consist, at a minimum, of the following:

a. A Regulatory Mechanism(s) that incorporates:

(1) A requirement that owners and/or operators of construction activity submit site plans with post-construction stormwater management BMPs to the permittee for review and approval, prior to start of construction activity

(2) Conditions for Post-Construction Stormwater Management:

The permittee shall develop and implement a Post-Construction Stormwater Management program that requires the use of any combination of BMPs, with highest preference given to Green Infrastructure techniques and practices (e.g., infiltration, evapotranspiration, reuse/harvesting, conservation design, urban forestry, green roofs, etc.), necessary to meet the following conditions on the site of a construction activity to the MEP:

(a) For new development projects – no net increase from pre-project conditions (on an annual average basis) of:

  1. Stormwater discharge Volume, unless precluded by the stormwater management limitations in Part III.D.5.a(3)(a)
  2. Stormwater discharges of Total Suspended Solids (TSS)
  3. Stormwater discharges of Total Phosphorus (TP)

(b) For redevelopment projects – a net reduction from pre-project conditions (on an annual average basis) of:

  1. Stormwater discharge Volume, unless precluded by the stormwater management limitations in Part III.D.5.a(3)(a)
  2. Stormwater discharges of TSS
  3. Stormwater discharges of TP

(3) Stormwater management limitations and exceptions

(a) Limitations

1) The permittee’s Regulatory Mechanism(s) shall prohibit the use of infiltration techniques to achieve the conditions for post-construction stormwater management in Part III.D.5.a(2) when the infiltration structural stormwater BMP will receive discharges from, or be constructed in areas:

a) Where industrial facilities are not authorized to infiltrate industrial stormwater under an NPDES/SDS Industrial Stormwater Permit issued by the Agency

b) Where vehicle fueling and maintenance occur

c) With less than three (3) feet of separation distance from the bottom of the infiltration system to the elevation of the seasonally saturated soils or the top of bedrock

d) Where high levels of contaminants in soil or groundwater will be mobilized by the infiltrating stormwater

2) The permittee’s Regulatory Mechanism(s) shall restrict the use of infiltration techniques to achieve the conditions for post-construction stormwater management, without higher engineering review, sufficient to provide a functioning treatment system and prevent adverse impacts to groundwater, when the infiltration device will be constructed in areas:

a) With predominately Hydrologic Soil Group D (clay) soils

b) Within 1,000 feet up-gradient, or 100 feet down-gradient of active karst features

c) Within a Drinking Water Supply Management Area (DWSMA) as defined in Minn. R. 4720.5100, subp. 13

d) Where soil infiltration rates are more than 8.3 inches per hour

3) For linear projects where the lack of right-of-way precludes the installation of volume control practices that meet the conditions for post-construction stormwater management in Part.III.D.5.a(2), the permittee’s Regulatory Mechanism(s) may allow exceptions as described in Part III.D.5.a(3)(b). The permittee’s Regulatory Mechanism(s) shall ensure that a reasonable attempt be made to obtain right-of-way during the project planning process.

(b) Exceptions for stormwater discharge volume

The permittee’s Regulatory Mechanism(s) may allow for lesser volume control on the site of the original construction activity than that in Part III.D.5.a(2) only under the following circumstances:

  1. The owner and/or operator of a construction activity is precluded from infiltrating stormwater through a designed system due to any of the infiltration related limitations described above, and
  2. The owner and/or operator of the construction activity implements, to the MEP, volume reduction techniques, other than infiltration, (e.g., evapotranspiration, reuse/harvesting, conservation design, green roofs, etc.) on the site of the original construction activity that reduces stormwater discharge volume, but may not meet the conditions for post-construction stormwater management in Part III.D.5.a(2).

(4) Mitigation provisions

There may be circumstances where the permittee or other owners and operators of a construction activity cannot cost effectively meet the conditions for post-construction stormwater management for TSS and/or TP in Part III.D.5.a(2) on the site of the original construction activity. For this purpose, the permittee shall identify, or may require owners or operators of a construction activity to identify, locations where mitigation projects can be completed. The permittee’s Regulatory Mechanism(s) shall ensure that any stormwater discharges of TSS and/or TP not addressed on the site of the original construction activity are addressed through mitigation and, at a minimum, shall ensure the following requirements are met:

(a) Mitigation project areas are selected in the following order of preference:

  1. Locations that yield benefits to the same receiving water that receives runoff from the original construction activity
  1. Locations within the same Department of Natural Resource (DNR) catchment area as the original construction activity
  2. Locations in the next adjacent DNR catchment area up-stream
  3. Locations anywhere within the permittee’s jurisdiction

(b) Mitigation projects must involve the creation of new structural stormwater BMPs or the retrofit of existing structural stormwater BMPs, or the use of a properly designed regional structural stormwater BMP.

(c) Routine maintenance of structural stormwater BMPs already required by this permit cannot be used to meet mitigation requirements of this Part.

(d) Mitigation projects shall be completed within 24 months after the start of the original construction activity.

(e) The permittee shall determine, and document, who is responsible for long-term maintenance on all mitigation projects of this Part.

(f) If the permittee receives payment from the owner and/or operator of a construction activity for mitigation purposes in lieu of the owner or operator of that construction activity meeting the conditions for post-construction stormwater management in Part III.D.5.a(2), the permittee shall apply any such payment received to a public stormwater project, and all projects must be in compliance with Part III.D.5.a(4)(a)-(e).

(5) Long-term maintenance of structural stormwater BMPs

The permittee’s Regulatory Mechanism(s) shall provide for the establishment of legal mechanism(s) between the permittee and owners or operators responsible for the long-term maintenance of structural stormwater BMPs not owned or operated by the permittee, that have been implemented to meet the conditions for post-construction stormwater management in Part III.D.5.a(2). This only includes structural stormwater BMPs constructed after the effective date of this permit, that are directly connected to the permittee’s MS4, and that are in the permittee’s jurisdiction. The legal mechanism shall include provisions that, at a minimum:

(a) Allow the permittee to conduct inspections of structural stormwater BMPs not owned or operated by the permittee, perform necessary maintenance, and assess costs for those structural stormwater BMPs when the permittee determines that the owner and/or operator of that structural stormwater BMP has not conducted maintenance.

(b) Include conditions that are designed to preserve the permittee’s right to ensure maintenance responsibility, for structural stormwater BMPs not owned or operated by the permittee, when those responsibilities are legally transferred to another party.

(c) Include conditions that are designed to protect/preserve structural stormwater BMPs and site features that are implemented to comply with Part III.D.5.a(2). If site configurations or structural stormwater BMPs change, causing decreased structural stormwater BMP effectiveness, new or improved structural stormwater BMPs must be implemented to ensure the conditions for post-construction stormwater management in Part III.D.5.a(2) continue to be met.

b. Site plan review

The program shall include written procedures for site plan reviews conducted by the permittee prior to the start of construction activity, to ensure compliance with requirements of the Regulatory Mechanism(s).

c. Documentation of the following information:

  1. Any supporting documentation used by the permittee to determine compliance with Part III.D.5.a, including the project name, location, owner and operator of the construction activity, any checklists used for conducting site plan reviews, and any calculations used to determine compliance
  2. All supporting documentation associated with mitigation projects authorized by the permittee
  3. Payments received and used in accordance with Part III.D.5.a(4)(f)
  4. All legal mechanisms drafted in accordance with Part III.D.5.a(5), including date(s) of the agreement(s) and name(s) of all responsible parties involved

6. Pollution Prevention/Good Housekeeping For Municipal Operations

New permittees shall develop and implement, and existing permittees shall revise their current program, as necessary, and continue to implement, an operations and maintenance program that prevents or reduces the discharge of pollutants from permittee owned/operated facilities and operations to the small MS4. The operations and maintenance program shall include, at a minimum, the following:

a. Facilities Inventory

The permittee shall develop and maintain an inventory of permittee owned/operated facilities that contribute pollutants to stormwater discharges. Facilities to be inventoried may include, but is not limited to: composting, equipment storage and maintenance, hazardous waste disposal, hazardous waste handling and transfer; landfills, solid waste handling and transfer, parks, pesticide storage, public parking lots, public golf courses; public swimming pools, public works yards, recycling, salt storage, vehicle storage and maintenance (e.g., fueling and washing) yards, and materials storage yards.

b. Development and Implementation of BMPs for inventoried facilities and municipal operations

Considering the source of pollutants and sensitivity of receiving waters (e.g., Outstanding Resource Value Waters (ORVWs), impaired waters, trout streams, etc.), the permittee shall develop and implement BMPs that prevent or reduce pollutants in stormwater discharges from the small MS4 and from:

  1. All inventoried facilities that discharge to the MS4, and
  2. The following municipal operations that may contribute pollutants to stormwater discharges, where applicable:

(a) Waste disposal and storage, including dumpsters

(b) Management of temporary and permanent stockpiles of materials such as street sweepings, snow, deicing materials (e.g., salt), sand and sediment removal piles

(c) Vehicle fueling, washing and maintenance

(d) Routine street and parking lot sweeping

(e) Emergency response, including spill prevention plans

(f) Cleaning of maintenance equipment, building exteriors, dumpsters, and the disposal of associated waste and wastewater

(g) Use, storage, and disposal of significant materials

(h) Landscaping, park, and lawn maintenance

(i) Road maintenance, including pothole repair, road shoulder maintenance, pavement marking, sealing, and repaving

(j) Right-of-way maintenance, including mowing

(k) Application of herbicides, pesticides, and fertilizers

(l) Cold-weather operations, including plowing or other snow removal practices, sand use, and application of deicing compounds

c. Development and implementation of BMPs for MS4 discharges that may affect Source Water Protection Areas (Minn. R. 4720.5100-4720.5590)

The permittee shall incorporate BMPs into the SWPPP to protect any of the following drinking water sources that the MS4 discharge may affect, and the permittee shall include the map of these sources with the SWPPP if they have been mapped:

  1. Wells and source waters for DWSMAs identified as vulnerable under Minn.R. 4720.5205, 4720.5210, and 4720.5330
  2. Source water protection areas for surface intakes identified in the source water assessments conducted by or for the Minnesota Department of Health (MDH) under the federal Safe Drinking Water Act, U.S.C. §§ 300j – 13

d. Pond Assessment Procedures and Schedule

The permittee shall develop procedures and a schedule for the purpose of determining the TSS and TP treatment effectiveness of all permittee owned/operated ponds constructed and used for the collection and treatment of stormwater. The schedule (which may exceed this permit term) shall be based on measureable goals and priorities established by the permittee.

e. Inspections

  1. Unless inspection frequency is adjusted as described below, the permittee shall conduct annual inspections of structural stormwater BMPs (excluding stormwater ponds which are under a separate schedule below) to determine structural integrity, proper function and maintenance needs.

    Inspections of structural stormwater BMPs shall be conducted annually unless the permittee determines if either of the following conditions apply: 1) Complaints received or patterns of maintenance indicate a greater frequency is necessary, or 2) Maintenance or sediment removal is not required after completion of the first two annual inspections; in which case the permittee may reduce the frequency of inspections to once every two (2) years. However, existing permittees are authorized under this permit to continue using inspection frequency adjustments, previously determined under the general stormwater permit for small MS4s No.MNR040000, effective June 1, 2006, provided that documentation requirements in Part III.D.6.h(2) are satisfied.
  2. Prior to the expiration date of this permit, the permittee shall conduct at least one inspection of all ponds and outfalls (excluding underground outfalls) in order to determine structural integrity, proper function, and maintenance needs.
  3. The permittee shall conduct quarterly inspections of stockpiles, and storage and material handling areas as inventoried in Part III.D.6.a, to determine maintenance needs and proper function of BMPs.

f. Maintenance

Based on inspection findings, the permittee shall determine if repair, replacement, or maintenance measures are necessary in order to ensure the structural integrity, proper function, and treatment effectiveness of structural stormwater BMPs. Necessary maintenance shall be completed as soon as possible to prevent or reduce the discharge of pollutants to stormwater.

g. Employee Training

The permittee shall develop and implement a stormwater management training program commensurate with employee’s job-duties as they relate to the permittee’s SWPPP, including reporting and assessment activities. The permittee may use training materials from the United States Environmental Protection Agency (USEPA), state and regional agencies, or other organizations as appropriate to meet this requirement. The employee training program shall:

  1. Address the importance of protecting water quality
  2. Cover the requirements of the permit relevant to the job duties of the employee
  3. Include a schedule that establishes initial training for new and/or seasonal employees, and recurring training intervals for existing employees to address changes in procedures, practices, techniques, or requirements

h. Documentation of the following information:

(1) Date(s) and description of findings of all inspections conducted in accordance with Part III.D.6.e

(2) Any adjustments to inspection frequency as authorized under Part III.D.6.e(1)

(3) A description of maintenance conducted, including dates, as a result of inspection findings

(4) Pond sediment excavation and removal activities, including:

(a) The unique ID number (consistent with that required in Part III.C.2.a) of each stormwater pond from which sediment is removed

(b) The volume (e.g., cubic yards) of sediment removed from each stormwater pond

(c) Results from any testing of sediment from each removal activity

(d) Location(s) of final disposal of sediment from each stormwater pond

(5) Employee stormwater management training events, including a list of topics covered, names of employees in attendance, and date of each event

E. Discharges to Impaired Waters with a USEPA-Approved TMDL that Includes an Applicable WLA

For each applicable WLA approved prior to the effective date of this permit, the BMPs included in the compliance schedule at application constitute a discharge requirement for the permittee. The permittee shall demonstrate continuing progress toward meeting each discharge requirement, on a form provided by the Commissioner, by submitting the following:

  1. An assessment of progress toward meeting each discharge requirement, including a list of all BMPs being applied to achieve each applicable WLA. For each structural stormwater BMP, the permittee shall provide a unique identification (ID) number and geographic coordinate. If the listed structural stormwater BMP is also inventoried as required by Mapping and Inventory Part III.C.2, the same ID number shall be used.
  2. A list of all BMPs the permittee submitted at the time of application in the SWPPP document compliance schedule(s) and the stage of implementation for each BMP, including any BMPs specifically identified for the small MS4 in the TMDL report that the permittee plans to implement
  3. An up-dated estimate of the cumulative reductions in loading achieved for each pollutant of concern associated with each applicable WLA
  4. An up-dated narrative describing any adaptive management strategies used (including projected dates) for making progress toward achieving each applicable WLA

F. Alum or Ferric Chloride Phosphorus Treatment Systems

If the permittee uses an alum or ferric chloride phosphorus treatment system, the permittee shall comply with the following:

1. Minimum Requirements of an Alum or Ferric Chloride Phosphorus Treatment System

a. Limitations

  1. The permittee shall use the treatment system for the treatment of phosphorus in stormwater. Non-stormwater discharges shall not be treated by this system.
  2. The treatment system must be contained within the conveyances and structural stormwater BMPs of a small MS4. The utilized conveyances and structural stormwater BMPs shall not include any receiving waters.
  3. Phosphorus treatment systems utilizing chemicals other than alum or ferric chloride must receive written approval from the Agency.
  4. In-lake phosphorus treatment activities are not authorized under this permit.

b. Treatment System Design

  1. The treatment system shall be constructed in a manner that diverts the stormwater flow to be treated from the main conveyance system.
  2. A High Flow Bypass shall be part of the inlet design.
  3. A flocculent storage/settling area shall be incorporated into the design, and adequate maintenance access must be provided (minimum of 8 feet wide) for the removal of accumulated sediment.

2. Monitoring During Operation

a. A designated person shall perform visual monitoring of the treatment system for proper performance at least once every seven (7) days, and within 24 hours after a rainfall event greater than 2.5 inches in 24 hours. Following visual monitoring which occurs within 24 hours after a rainfall event, the next visual monitoring must be conducted within seven (7) days after that rainfall event.

b. Three benchmark monitoring stations shall be established. Table B-1 shall be used for the parameters, units of measure, and frequency of measurement for each station.

c. Samples shall be collected as grab samples or flow-weighted 24-hour composite samples.

d. Each sample, excluding pH samples, must be analyzed by a laboratory certified by the MDH and/or the MPCA, and:

  1. Sample preservation and test procedures for the analysis of pollutants shall conform to 40 CFR Part 136 and Minn. R. 7041.3200.
  2. Detection limits for dissolved phosphorus, dissolved aluminum, and dissolved iron shall be a minimum of 6 micrograms per liter (µg/L), 10 µg/L, and 20 µg/L, respectively.
  3. pH must be measured within 15 minutes of sample collection using calibrated and maintained equipment.
MS4 Table B-1:Monitoring Parameters During Operation
Link to this table
Station Alum Parameters Ferric Parameters Units Frequency
Upstream-Background Total Phosphorus Total Phosphorus mg/L 1 x week
Dissolved Phosphorus Dissolved Phosphorus mg/L 1 x week
Total Aluminum Total Iron mg/L 1 x week
Dissolved Aluminum Dissolved Iron mg/L 1 x week
pH pH SU 1 x week
Flow Flow Mgd Daily
Alum or Ferric Chloride Feed Alum Ferric Gallons Daily Total Dosed In Gallons
Discharge From Treatment Total Phosphorus Total Phosphorus mg/L 1 x week
Dissolved Phosphorus Dissolved Phosphorus mg/L 1 x week
Total Aluminum Total Iron mg/L 1 x week
Dissolved Aluminum Dissolved Iron mg/L 1 x week
pH pH SU 1 x week
Flow Flow Mgd Daily

e. In the following situations, the permittee shall perform corrective action(s) and immediately notify the Minnesota Department of Public Safety Duty Officer at 1-800-422-0798 (toll free) or 651-649-5451 (Metro area):

  1. The pH of the discharged water is not within the range of 6.0 and 9.0
  2. Any indications of toxicity or measurements exceeding water quality standards
  3. A spill, as defined in Minn. Stat. § 115.01, subd. 13, of alum or ferric chloride

3. Reporting and Recordkeeping

a. Annual Reporting

The permittee shall submit the following information with the Annual Report in [MS4 PART IV. ANNUAL SWPPP ASSESSMENT, ANNUAL REPORTING AND RECORD KEEPING#B. Annual Reporting|Part IV.B]. The Annual Report must include a month-by-month summary of:

  1. Date(s) of operation
  2. Chemical(s) used for treatment
  3. Gallons of water treated
  4. Gallons of alum or ferric chloride treatment used
  5. Calculated pounds of phosphorus removed
  6. Any performance issues and the corrective action(s), including the date(s) when corrective action(s) were taken

b. On-Site Recordkeeping

A record of the following design parameters shall be kept on-site:

(1) Site-specific jar testing conducted using typical and representative water samples in accordance with ASTM D2035-08 (2003)

Baseline concentrations of the following parameters in the influent and receiving waters:

(a) Aluminum or Iron

(b) Phosphorus

(3) The following system parameters and how each was determined:

(a) Flocculent settling velocity

(b) Minimum required retention time

(c) Rate of diversion of stormwater into the system

(d) The flow rate from the discharge of the outlet structure

(e) Range of expected dosing rates

4. Treatment System Management

The following site-specific procedures shall be developed and a copy kept on-site:

a. Procedures for the installation, operation and maintenance of all pumps, generators, control systems, and other equipment

b. Specific parameters for determining when the solids must be removed from the system and how the solids will be handled and disposed of

c. Procedures for cleaning up and/or containing a spill of each chemical stored on-site

G. Stormwater Pollution Prevention Program (SWPPP) Modification

1. The Commissioner may require the permittee to modify the SWPPP as needed, in accordance with the procedures of Minn. R. ch. 7001, and may consider the following factors:

a. Discharges from the small MS4 are impacting the quality of receiving waters.

b. More stringent requirements are necessary to comply with state or federal regulations.

c. Additional conditions are deemed necessary to comply with the goals and applicable requirements of the Clean Water Act and protect water quality.

2. Modifications that the permittee chooses to make to the SWPPP document developed under Part II.D, other than modifications authorized in Part III.G.3 below, must be approved by the Commissioner in accordance with the procedures of Minn. R. ch. 7001. All requests must be in writing, setting forth schedules for compliance. The request must discuss alternative program modifications, assure compliance with requirements of the permit, and meet other applicable laws.

3. The SWPPP document may only be modified by the permittee without prior approval of the Commissioner provided it is in accordance with a. or b. below, and the Commissioner is notified of the modification in the Annual Report for the year the modification is made.

a. A BMP is added, and none subtracted, from the SWPPP document.

b. A less effective BMP identified in the SWPPP document is replaced with a more effective BMP. The alternate BMP shall address the same, or similar, concerns as the ineffective or failed BMP.

This page was last modified on 3 February 2015, at 08:53.

Minnesota Pollution Control Agency | 651-296-6300, 800-657-3864 | Assistance | Web site policy