The requirements in Sector N apply to stormwater discharges associated with industrial activity from scrap recycling and waste recycling facilities, as identified by the industrial activity code specified in Table 5 of Appendix D.
a. Processing, reclaiming, and wholesale distribution of scrap and waste materials, such as ferrous and nonferrous metals, paper, plastic, cardboard, glass, and animal hides.
b. Reclaiming and recycling of liquid wastes, such as used oil, antifreeze, mineral spirits, and industrial solvents.
Non-stormwater discharges from ferrous and non-ferrous metal turnings containment areas are not authorized by this permit.
4. Sector -Specific Definitions (No Additional Definitions)
5. Stormwater Controls
a. Employee Training (No additional requirements).
b. Erosion and Sedimentation Controls (No additional requirements).
c. Good Housekeeping.
The Permittee shall minimize exposure of recyclables to precipitation and runoff and use good housekeeping measures to prevent accumulation of particulate matter and fluids, particularly in high traffic areas.
1. The Permittee shall minimize acceptance of materials that may be significant sources of pollutants by conducting inspections of the in-bound materials.
2. In addition to the inspection requirements outlined in Part III.G, the Permittee shall ensure that a total of two (2) of the required monthly inspections occur during runoff events, with at least one being performed during snow melt.
Each inspection shall include a visual assessment of the runoff to identify any visible sheens or films that indicate the presence of oil or grease in the discharge. If sheens are present in stormwater discharges, corrective actions to prevent sheen shall be implemented and documented in the SWPPP.
The Permittee is only required to conduct visual inspections of runoff originating from, or passing through, areas of industrial activity and/or significant materials. Any runoff that does not contact industrial activity and/or significant materials (e.g. office buildings, employee parking lots, natural areas, etc) is not required to be inspected.
e. Preventive Maintenance (No additional requirements).
f. Spills and Leaks (No additional requirements).
g. Management of Runoff.
The Permittee shall minimize;
1. Contact of stormwater runoff with stockpiled scrap materials, processed materials, storage of materials and non-recyclable wastes.
2. Contact of surface runoff with stockpiles of turnings exposed to cutting fluids by:
a. Storing all turnings exposed to cutting fluids under some form of permanent or semi-permanent cover.
b. Establishing dedicated containment areas for all turnings that have been exposed to cutting fluids. Stormwater runoff from these areas can be discharged, provided that any runoff is first collected and treated by an oil and water separator or its equivalent. The Permittee shall regularly maintain the oil and water separator (or its equivalent) and properly dispose of or recycle collected residual fluids.
3. Contact of stormwater with residual liquids, particulate matter, and waste materials that are stored either outdoors or under cover.
4. Surface runoff from coming in contact with scrap processing equipment, including operations that generate visible particulate residue (e.g. shredding).
5. Pollutants in discharges from truck and rail car loading and unloading areas, and must include measures to clean up spills and leaks resulting from the transfer of liquid wastes.
h. Other Industry Specific Stormwater Control Measures.
1. The Permittee shall notify major suppliers about which scrap materials will not be accepted at the facility or will be accepted only under certain conditions.
2. The Permittee shall properly handle, store, and manage scrap lead-acid batteries.
6. SWPPP Requirements
The SWPPP may refer to applicable portions of other existing plans, such as SPCC plans required under 40 CFR pt. 112. In addition to the requirements of Part IV, the Permittee shall also comply with the following:
a. Facility Map.
The Permittee shall identify the locations of any of the following activities or sources that may be exposed to stormwater:
1. Outdoor scrap and waste processing equipment.
2. Containment areas for turnings exposed to cutting fluids.
b. Inventory of Exposed Materials (No additional requirements).
c. Potential Pollutant Sources (No additional requirements).
d. Description of Stormwater Controls (No additional requirements).
7. Monitoring and Reporting Requirements
In accordance with the monitoring requirements of Part V, the Permittee shall monitor the applicable parameters in Table N-1, below:
Sector-Specific Benchmark Values and Effluent Limitations: Sector - N. Discharges may be subject to requirements for more than one sector or subsector.
Link to this table
|N1 Scrap Recycling Facilities||Solids, Total Suspended (TSS)||100 mg/L 2|
|COD (Chemical Oxygen Demand)||120 mg/L|
|Aluminum, Total (as Al)||1.5 mg/L|
|Copper, Total (as Cu)||0.028 mg/L 1|
|Iron, Total (as Fe)||1.0 mg/L|
|Lead, Total (as Pb)||0.164 mg/L 1|
|Zinc, Total (as Zn)||0.234 mg/L 1|
|pH 3||6.0-9.0 SU|
1The benchmark values of some metals are influenced by water hardness. For these parameters, the Permittee may determine the hardness of the stormwater discharges to identify the applicable ‘hardness range’ for determining their benchmark value. See Table 4 of Appendix B for hardness dependent benchmark values in accordance with Minn. R. 7050.0222 and Minn. R. 7052.0100.
2If the Permittee is required to comply with Appendix A, part F.1, the benchmark value for Solids, Total Suspended (TSS) is 65 mg/L, instead of 100 mg/L.
3For purposes of benchmark pH monitoring, the Permittee is required to report instantaneous results only, and not a calculation of pH averages. pH measurements are logarithmic, and the Agency will be performing a logarithmic average for this parameter using the instantaneous results submitted.
8. Use of Infiltration Devices and/or Industrial Stormwater Ponds for Stormwater Treatment and Disposal
a. Industrial Stormwater Ponds
1. The Permittee of a sector N industrial facility is authorized to use industrial stormwater ponds for stormwater management provided that any industrial stormwater pond constructed after the effective date of this permit meets the following design criteria. Any Permittee required to comply with this part is not authorized to utilize the benchmark monitoring waiver described in Part V.B.6.a of the permit.
a. The industrial stormwater pond must be lined with a synthetic liner that is chemically compatible with materials expected to enter the pond, must be Ultra Violet (UV) stable, and must be designed to restrict infiltration to less than 500 gallons per acre per day.
b. The industrial stormwater pond must be designed in accordance with accepted engineering practices. (See Agency “Recommended Pond Design Criteria” December 2009, Document number: wq-wwtp5-53 and any applicable supporting technical criteria)
b. Infiltration Devices
1. The Permittee of a sector N industrial facility is authorized to use a designed infiltration device, implemented prior to the effective date of this permit, for stormwater management provided the Permittee complies with the following requirements:
a. The Permittee shall conduct benchmark monitoring in accordance with the terms and conditions of Part V of all industrial stormwater prior to infiltration. However, any Permittee required to comply with this part that is using a designed infiltration device to manage industrial stormwater is not authorized to utilize the benchmark monitoring waiver described in Part V.B.6.a of the permit.
b. If the Permittee has a designed infiltration device operating prior to the effective date of this permit, the Permittee is authorized to continue using that device. However, on or after the effective date of this permit, the Permittee is not authorized to construct new infiltration devices, expand infiltration activities or practices that result in infiltration, or expand volume of infiltration.
a. All vehicle recyclers and vehicle scrap processors shall remove and manage and recycle mercury containing convenience lighting switch assemblies, mercury containing ABS switch assemblies, and mercury containing air bag sensor switch assemblies found in some vehicles manufactured before model year 2002. Under Minn. Stat. 116.92, Subd 4(c), “A person may not crush a motor vehicle unless the person has first made a good faith effort to remove all of the mercury switches in the motor vehicle.”
b. In addition, the Permittee shall also evaluate the facility to identify any additional sources of mercury that may be introduced to, or used at, the facility. This may include but is not limited to mercury containing devices such as float switches, tilt switches, manometers, barometers, batteries, flame sensors (diostats), hydrometers, medical devices, lamps, mercury compounds, pyrometers, displacement relays, wetted reed relays, thermometers, pressure gauges, thermostats, etc. The plan shall describe how the Permittee is removing mercury containing devices, segregating mercury containing devices to avoid spills and contact with stormwater, and the methods used for recycling any mercury generated at the facility (including the specific recycling program used). All mercury and mercury-containing devices must be removed and recycled in accordance with Minn. Stat. §§ 115A.932 and 116.92 and in accordance with state and federal Universal Waste Rules and other applicable water, air, and waste regulations.