The COGCC_Fields layer represents the approximate boundaries of oil and gas fields in Colorado. These field boundaries are defined by producing and/or plugged and abandoned wells within the field. The appropriate field designation for each well is decided on a well by well basis by COGCC staff. The COGCC_Fields polygons are updated on a periodic basis using an ArcGIS model that reads the field codes from the COGIS database for each well, groups the wells by field code, and creates a series of buffers around the grouped wells. All field polygons are included in this shapefile with the exception of the Wattenberg Field polygon.