In 2019, Broomfield tested and found methane in the soils around the Davis 43-6 plugged and abandoned well, which is located on Graham Peak Way in Anthem Highlands. After requests from Broomfield, the Colorado Oil and Gas Conservation Commission (COGCC) repaired the well. The repair of the well occurred by drilling to a depth of 2,997 feet, recementing numerous zones in the well, and filling voids in the original surface casing. A map showing the location of the well can be viewed here.
The COGCC continued the soil gas testing in the area of the Davis 43-6 plugged and abandoned well through January and February 2020 to determine if the residual methane in the soils would dissipate naturally. The COGCC testing determined there is still methane in the soil at depths of approximately 18 feet that has not dissipated, which the COGCC staff believes is due to the tight compaction of the soil above the well.
It is important to note that the methane readings are subsurface and staff at the COGCC indicated verbally there is not a public safety issue as these are "tiny, pinpoint areas" where the methane readings are higher. The North Metro Fire Rescue District has tested the air in the area and found no issues of concern.
Broomfield has urged the COGCC to take additional steps to address the methane at that depth. In response, the COGCC hired a company to design and install a soil vapor extraction system (SVE) on the site in order to extract the methane vapors via vacuum. The COGCC notes that this process will specifically be designed for the extent and depth of the site as well as the subgrade material.
On March 13, 2020, Broomfield Oil and Gas Division staff participated in a conference call with the COGCC and the company, Antea Group (Antea), contracted to design and install the SVE for the Davis 43-6.
Next steps in this process are:
Antea staff will do a thorough review of the soil gas, groundwater, and well re-plugging information. This data review will occur over the next one to two weeks.
It is anticipated that following the data review, Antea will schedule a site visit with the COGCC and Broomfield staff to better understand the site conditions to aid in the design of the soil gas treatment plan. This meeting is tentatively scheduled for March 30th.
Antea will take the actions determined appropriate, which will likely include the design and install of the SVE
Updates on this process will be provided as additional information becomes available.
For more information, please call Broomfield staff at 303.464.5153 or email firstname.lastname@example.org.