NYT: A power plant has overexposed its workers to radiation, and the Nuclear Regulatory Commission is proposing a fine. The plant, though, is not a reactor; it runs on coal. The commission said on Monday that it was proposing a fine of $24,700 against the Basin Electric Power Cooperative, which exposed 17 workers, six of them above regulatory limits, at a three-unit coal plant in Laramie, Wyo. The workers were exposed to a radioactive element, cesium 137, that is common in nuclear …