The Department of Justice, the U.S. Environmental Protection Agency (EPA), and the State of Colorado...announced a settlement with Denver-based PDC Energy, Inc. resolving Clean Air Act violations alleged in a civil complaint... [which] alleged that PDC violated requirements to reduce volatile organic compound (VOC) emissions from its oil and gas exploration and production activities in the Denver area... PDC will spend an estimated $18 million on system upgrades, improved operations and maintenance practices, monitoring, and inspections to reduce emissions. PDC will also be required to implement environmental mitigation projects at certain sites to further reduce VOC and nitrogen oxide emissions... The settlement includes a $2.5 million civil penalty, which will be split evenly between the United States and the State of Colorado...