A Republican lawmaker from Libby on Wednesday spoke on behalf of a bill that seeks to strike the existing water quality standard for selenium in Lake Koocanusa and double the limit.

Selenium is a chemical element entering Lake Koocanusa, a reservoir shared by British Columbia and Montana, from Canadian mining company Teck Coal. Even in small quantities, selenium can hamper reproductive success in fish. Selenium toxicity can also lead to spinal and facial deformities in fish.