A Tennessee worker who supervises the state’s regulation of oil and gas production says opponents of hydraulic fracturing are, in his words, “stupid.” Michael Burton’s comment was found in handwritten notes on emails sent to the Tennessee Department of Environment and Conservation. The emails solicited public comment on new regulations for hydraulic fracturing. The process, also known as fracking, extracts natural gas from rock by injecting high pressure mixtures of sand, water or gravel and chemicals. Burton says his notes were not intended to go public and that he was venting his frustration on paper. He has since apologized. The TDEC disapproves of his comments and has talked with him about them, but Burton has not been formally disciplined.