EPA aims to get tougher on stormwater permitting

The Environmental Protection Agency (EPA) is about to announce revisions to the permits various metalworking sectors need to obtain for stormwater discharges.

Companies in these industrial segments have to deal with unique sector subpermits, each with some general and then specific monitoring and reporting requirements. For instance, permits for scrap recycling facilities fall under Sector N and fabricated metal products fall under Sector AA. The permits last for five years, and the one issued in 2015 expired on June 1, 2020, ensuring that the EPA will publish a new five-year permit soon.

That new permit will reflect changes suggested by a National Academy of Sciences (NAS) panel that was set up as a condition of the settlement of a number of lawsuits filed by industry and environmental groups after the 2015 permit was published under the Obama administration. What makes this a very important issue for the fabricated metals sector is the NAS report found several industries, including fabricated metals, exceeded annual benchmarks for aluminum 36% of the time and zinc 74% of the time. Moreover, each sector, including fabricated metals, has to test for the presence of various metals in discharged wastewater, and the testing methods the EPA wants to prescribe have come under heavy fire for various reasons.

Each permit has a benchmark level for particular chemicals and metals, and if those benchmarks are exceeded, the company is required to take certain steps. In the new proposed permit, whose formal moniker is the 2020 Multi-Sector General Permit (MSGP), the EPA would affect metals-related businesses in a couple of ways:

1. It would modify benchmark thresholds for selenium, arsenic, cadmium, magnesium, iron, and copper based on the latest toxicity information.
2. EPA-proposed additional implementation measures (AIM) would be triggered if benchmark thresholds are surpassed. Each of the three AIM tier levels is marked by increasingly more robust control measure requirements. EPA’s proposed AIM for Tier 2, for instance, requires facilities that exceed benchmarks by modest thresholds to adopt all feasible controls identified on EPA’s proposed sector-specific fact sheets. For the scrap recycling sector, that would mean nearly 200 requirements.

Denny Wene, senior environmental consultant, Howmet Inc., which fabricates metal parts for the aerospace industry, is not a big fan of the proposed changes.

“Howmet believes that the implementation of the AIM methodology is not justified because the derivation of the benchmarks is questionable, the manner in which some benchmarks are derived is overly conservative, the risk to aquatic life is minimal, and the costs for complying with incorrect science are quite high,” he said.

Last, the EPA proposes to require all facilities to conduct what is called universal benchmark monitoring for three indicator parameters of pH, total suspended solids (TSS), and chemical oxygen demand (COD). The Steel Manufacturers Association and the Specialty Steel Industry of North America submitted joint comments that took issue with two of the changes.

“The requirement for universal benchmark monitoring of pH, TSS, and COD is not necessary to assure the effectiveness of stormwater control measures at facilities operated by members of the steel associations,” they wrote in a public statement.

The National Association for Surface Finishing (NASF) pointed out that the quarterly monitoring frequency for universal benchmark monitoring is excessive, burdensome, and unnecessarily expensive, especially for small businesses that make up the surface finishing industry. The NASF is pushing the EPA to consider effective and less burdensome ways to address these benchmark parameters, including visual monitoring and inspections.