EPA is expected to propose a revised system of benchmark monitoring and corrective action requirements to replace those of the current 2015 Multi-Sector General Permit for Stormwater Associated with Industrial Activities (MSGP). EPA has just entered into a settlement agreement with environmental groups that challenged EPA’s issuance of the 2015 MSGP, under which EPA has agreed to propose a number of new conditions for incorporation into the next version of the permit. The settlement agreement has no effect on the terms and conditions of the current 2015 MSGP, which remains in place until June 2020, however, facilities subject to benchmark monitoring should take note of the changes expected to be proposed, particularly for those facilities consistently facing benchmark exceedances. Under the current permit, benchmark exceedances do not on their own result in non-compliance but can trigger the need for enhanced stormwater management practices.

Benchmark Monitoring

The settlement agreement covers several stormwater management issues but places a strong emphasis on benchmark monitoring. EPA has agreed to both study the effectiveness of the 2015 MSGP’s benchmark monitoring provisions and to propose a tiered set of corrective action measures. The proposed tiered system’s structure builds on sample results from year-to-year, and its increasingly sophisticated action requirements will translate into a need to make greater capital expenditures and to consult more regularly with professional engineers.

We summarize the proposed tiers in the attached table, with a comparison point to the 2015 MSGP’s requirements in the first row of the chart.

Eligibility Under MSGP

EPA has also agreed to propose a provision extending the discharge authorization date from 30 to 60 days for new dischargers (i.e., facilities not covered under the 2015 MSGP) that submit an NOI while subject to a pending stormwater enforcement action by EPA, a state, or a citizen group, including any facility that has received a citizen group’s Notice of Intent to Sue. This means that EPA would be alerted of alleged stormwater violations at the time of a facility’s application for permit coverage and may take the opportunity to impose additional stormwater control requirements.

EPA will also propose that facilities with pavement coated with coal tar sealant will not be eligible for permit coverage under the MSGP. Facilities would need to eliminate the discharge of PAHs from the coal tar sealant before seeking permit coverage, which would likely require repaving.

Other Provisions

In addition, EPA also agreed to the following:

• Fund a study by the National Resource Council to evaluate and provide recommendations on:
  • Suggested improvements to the current MSGP’s benchmark monitoring requirements; 
  • Feasibility of numeric retention standards; and
  • Identification of the highest priority industrial facilities or industrial sectors to consider for more stringent discharge requirements;
• Revise EPA’s sector-specific fact sheets to incorporate emerging stormwater control measures that reflect industry practices for Best Available Technology (BAT) and Best Control Technology (BCT);
• Propose in the next MSGP to extend the eligibility criterion for facilities discharging to federal CERCLA sites to all EPA Regions; and
• Propose in the next MSGP annual monitoring requirements for stormwater discharging to impaired waters without a TMDL.

While the proposed MSGP will not be issued for at least three years, facilities subject to the 2015 MSGP should be aware that the study recommendations together with the conceptual benchmark and eligibility provisions described above could significantly change facilities’ response obligations to monitoring and sampling requirements under the permitting program. It could also widen the net of facilities subject to the permitting program, or even result in a shift in focus to specific “high-priority” industrial sectors.

Facilities currently struggling to meet benchmark thresholds may want to start the planning process to consider the steps that can be taken to reduce benchmark exceedances. If EPA ultimately adopts the proposed conditions, facilities with consistently high benchmark exceedances may expose themselves to increased federal or citizen group oversight.