Through U.S. Department of Interior funding as part of the Infrastructure Investment and Jobs Act (Bipartisan Infrastructure Law), the Arizona Department of Environmental Quality is working in partnership with the Arizona Oil and Gas Conservation Commission to plug, abandon, and reclaim orphaned oil and gas wells and well sites on State and private land to reduce greenhouse gas emissions, protect groundwater, and restore the land. As part of these efforts, Weston has performed site assessment/characterization of 21 abandoned or orphan wells in Maricopa County, AZ. Weston faced many site challenges from open desert rangeland, irrigated farmland, to mixed-use commercially developed areas, and residential subdivisions.
Additionally, most of these wells did not have commercial oil and gas production, and as a result had little or no surface infrastructure to assist in locating the well or boring. To more efficiently locate and understand the well conditions, Weston compiled all available hard copy and electronic files and reports, historical aerial photographs, and environmental database information; conducted land and mineral title searches to evaluate whether the wells met orphan well criteria; interviewed stakeholders; performed walking inspections; conducted drone and hand-held geophysical surveys; and identified property owners to secure rights of entry for assessment and plugging activities. Because the wells were drilled before global positioning satellite data existed, Weston aligned historical data with modern coordinates to better approximate actual well locations. Using all the information gathered, we prepared a summary report for each well that determined 7 of the 21 wells did not meet orphan well criteria, and therefore were excluded from response actions. Weston is now preparing initial assessments for an additional 41 wells. Subsequent work will include collection of soil and groundwater samples for site investigation, plugging orphan wells, and site restoration.
