The federal government has signed off on a controversial proposal to change the way Kentucky measures selenium pollution in state waterways. The Environmental Protection Agency sent a letter with its decision today.
Selenium is a naturally-occurring substance that’s released into waterways during strip mining. In large amounts, it’s toxic to both aquatic life and humans. The substance also bioaccumulates up the food chain, so as fish eat other fish, levels of selenium rise.
Right now, Kentucky’s water quality standard for selenium is based on the amount of the substance that’s in the water. If testing reveals levels of selenium that are higher than is allowed, there’s a problem. But the new standard changes the chronic selenium standard into a two-part process: if water testing reveals levels that are above a certain benchmark, that will trigger fish tissue testing.
This new standard was touted by the commonwealth and supported by the coal industry, but was actively opposed by environmental groups. That fish tissue sampling was a sticking point; environmental advocates argued that high levels of selenium could making finding fish to sample difficult. Here’s what attorney Mary Cromer of the Appalachian Citizens Law Center in Whitesburg told me in August:
“So if you have any kind of chronic selenium problem, in a very short period of time you’re going to be extirpating the sensitive fish,” she said. “Let’s say you’re going a mile downstream or two miles downstream until you can find these fish. Well, what if you have five valley fills upstream? What if you have 20 valley fills upstream? There’s been no answer as to what enforcement would look like for those valley fills. It becomes an attenuated causation problem.”
But the EPA agreed with the Kentucky Department for Environmental Protection that the new standard is based on the latest scientific research. And clarifies: “in the event that sufficient fish tissue cannot be obtained, the permit holder will be deemed to be in non-compliance with the proposed KPDES permit for exceeding the chronic trigger level of 5.0 µg/L.”
The EPA didn’t, however, agree to the way Kentucky proposed to measure the short-term, or acute, selenium standard. In a blog post, the Kentucky Department for Environmental Protection says that means the previous standard of 20 µg/L will remain in place.