EPA Proposes the 2020 Reissuance of Multi-Sector General Stormwater Permit

Multi-Sector General Permit

Comment period extended until May 31, 2020.

The Environmental Protection Agency (EPA) has announced the proposed 2020 National Pollution Discharge Elimination System (NPDES) Multi-Sector General Permit (MSGP).  The EPA is seeking public comment on the proposed changes until May 31, 2020. Upon approval, these changes would replace the 2015 MSGP for stormwater discharge related to industrial facilities in areas where the EPA is the NPDES permitting authority.

According to the EPAs website, changes to the proposed 2020 MSGP include:

Streamlining the permit

EPA proposed to streamline and simplify language throughout the permit to present the requirements in a generally more clear and readable manner.

Eligibility for stormwater discharges to a federal CERCLA site
The 2015 MSGP requires facilities in EPA Region 10 that discharge stormwater to certain CERCLA or Superfund sites to notify the EPA Regional Office in advance and requires EPA Regional Office to determine whether the facility is eligible for permit coverage. In the proposed 2020 MSGP, EPA requests comment on whether this current eligibility criterion should be applied in all EPA Regions for facilities that discharge to Federal CERCLA sites that may be of concern for recontamination from stormwater discharges. See Part 1.1.7 in the proposed permit and fact sheet, and request for comment 1.

Eligibility related to application of coal-tar sealcoat
EPA proposes that operators, who will use coal-tar sealcoat to initially seal or to re-seal their paved surfaces where industrial activities are located and thereby discharge polycyclic aromatic hydrocarbons (PAHs) in stormwater, would be eligible for coverage under the 2020 MSGP only if they eliminate such discharge(s). Alternatively, operators who wish to pave their surfaces where industrial activities are located with coal-tar sealcoat may apply for an individual permit. See Part 1.1.8 of the proposed permit and fact sheet, and request for comment 2.

Discharge authorization related to enforcement action
EPA proposes to establish a discharge authorization waiting period of 60 calendar days after NOI submission for any operators whose discharges were not previously covered under the 2015 MSGP and who have a pending stormwater-related enforcement action by EPA, a state, or a citizen (to include both NOVs by EPA or a state and notices of intent to bring a citizen suit). See Part 1.3.3, Table 1-2 of the proposed permit and fact sheet, and request for comment 4.

Public sign of permit coverage
EPA proposes that the 2020 MSGP include a requirement that MSGP operators must post a sign of permit coverage at a safe, publicly accessible location in close proximity to the facility. See Part 1.3.6 of the proposed permit and fact sheet, and request for comment 6.

Consideration of major storm control measure enhancements
EPA proposes that operators would be required to consider implementing enhanced measures for facilities located in areas that could be impacted by stormwater discharges from major storm events that cause extreme flooding conditions. See Part 2.1.1.8 of the proposed permit and fact sheet, and request for comment 8.

Universal benchmark monitoring for all sectors
EPA proposes to require all facilities to conduct benchmark monitoring for three indicator parameters of pH, Total Suspended Solids, and Chemical Oxygen Demand, called universal benchmark monitoring. See Part 4.2.1 of the proposed permit and fact sheet, and requests for comment 10 and 13.

Impaired waters monitoring
Under the 2015 MSGP, operators discharging to impaired waters must monitor once per year for pollutants for which the waterbody is impaired and can discontinue monitoring if these pollutants are not detected or not expected in the discharge. EPA proposes to require operators discharging to impaired waters to monitor only for those pollutants that are both causing impairments and associated with the industrial activity and/or benchmarks. The proposal specifies that, if the monitored pollutant is not detected in the discharge for three consecutive years, or it is detected but the operator has determined that its presence is caused solely by natural background sources, operators may discontinue monitoring for that pollutant. See Part 4.2.4.1 of the proposed permit and fact sheet.

Updating benchmark values
EPA proposes to modify and/or requests comment on benchmark thresholds for selenium, arsenic, cadmium, magnesium, iron, and copper based on the latest toxicity information. See Parts 4.2.1 and 8 of the proposed fact sheet and fact sheet, and requests for comment 14, 15, 16, 17, 18, and 19.

Sectors with new benchmarks
The 2015 MSGP does not require sector-specific benchmark monitoring for Sector I (Oil and Gas Extraction), Sector P (Land Transportation and Warehousing), or Sector R (Ship and Boat Building and Repair Yards). Based on the NRC study recommendation which identified potential sources of stormwater pollution from these sectors, EPA proposes to add benchmark monitoring requirements for these three sectors. See Part 8 of the proposed permit, Parts 4.2.1.1 and 8 of the proposed fact sheet, and request for comment 12.

Additional implementation measures
EPA proposes revisions to the 2015 MSGP’s provisions regarding benchmark monitoring exceedances. EPA proposes new tiered Additional Implementation Measures (AIM), that are triggered by benchmark monitoring exceedances. Operators would be required to respond to different AIM levels with increasingly robust control measures depending on the nature and magnitude of the benchmark threshold exceedance. See Part 5.2 of the proposed permit and fact sheet, and requests for comment 21, 22, 23, and 26.

 Revisions to sector-specific fact sheets
EPA proposes updates to the existing sector-specific fact sheets that include information about control measures and stormwater pollution prevention for each sector to incorporate emerging stormwater control measures. See Part 5.2.2.2 and Appendix Q of the proposed permit and fact sheet.

Learn more about these changes: https://www.epa.gov/npdes/stormwater-discharges-industrial-activities

Submit your comment to the EPA on these proposed 2020 NPDES MSGP before May 31, 2020.

If you have any additional questions, NGE has extensive experience with all aspects of stormwater compliance including modification of SWPPP’s and GPP’s and stormwater sampling and reporting.

Contact NGE’s Environmental Services Division for your stormwater compliance needs.

Have a project for NGE?

To team with NGE on your next project, reach out to us using our contact form!