A public interest law firm and a group of citizens on Thursday asked Cathy Stepp, regional administrator of the U.S. Environmental Protection Agency, to step aside from any involvement in the federal agency’s ongoing review of Wisconsin’s water pollution program. Stepp, a Republican, oversaw all environmental regulations in Wisconsin, including water issues, as secretary of the Department of Natural Resources from 2011 until August of last year. She was appointed to the post by Gov. Scott Walker. The EPA has been monitoring the state’s water program for years. In July 2011, the federal agency cited 75 shortcomings, or deficiencies, and ordered the DNR to fix the problems within two years. Some matters date back to before the start of the Walker administration. The deficiencies largely involve technical issues designed to assure Wisconsin is properly enforcing water regulations. The issues range from allowable limits for pollutants and management of storm water to an examination of whether the DNR has adequate state authority to carry out its work. Frustrated by the pace of the state’s response, Midwest Environmental Advocates and a group of 16 citizens asked the EPA in October 2015 to conduct a formal review of the DNR’s water pollution program. The groups filed what is known as a petition for corrective action that could strip the DNR of its oversight of state water programs, if the EPA concluded that the state’s efforts were falling short. In October 2016, EPA personnel inspected DNR records at its headquarters in Madison as part…