EPA inspected a company and found numerous violations, including “failure to implement corrective actions following continued benchmark exceedances.” According to EPA’s news release announcing settlement of an enforcement action, the company will pay $225,000 in penalties and implement “extensive remedies to come into and remain in compliance.”

Operators Must Act when Benchmarks Exceeded
Stormwater permits, both general and specific, can have effluent limits and benchmark limits. Exceeding an effluent limit is evidence of a permit violation. Exceeding a benchmark limit is not evidence of a permit violation; however, permits require actions when benchmarks are exceeded. Failure to act can lead to enforcement and penalties.

Typical actions required by stormwater permits for a benchmark exceedance include review of existing control measures to determine if any different measures or revisions to the stormwater pollution prevention plan (SWPPP) are necessary. The review should examine sources of pollution, spill and leak procedures, non-stormwater discharges, and selection, design, installation, and implementation of control measures. After reviewing the control measures and SWPPP, the operator must make any necessary changes to the SWPPP and implement the measures necessary to bring the discharged stormwater below the parameter’s benchmark threshold.

Document and Report if No Changes Made
If the operator determines no changes are needed to the SWPPP or to other control measures, the operator must document and include in an annual report why it expects to bring the discharge below the benchmark within the next 12 months without making any changes.

To see the news release https://www.epa.gov/newsreleases/idaho-company-penalized-225000-clean-water-act-violations-along-st-joe-river