Dimock Gas Migration Investigation

This page contains information associated with DEP's investigation, beginning in January 2009, into a gas migration incident affecting private water supplies and involving nearby Cabot Oil & Gas Corporation (“Cabot”) gas wells. This page will be updated periodically as selected information of potential public interest becomes available. Information will be posted chronologically with newest material at the bottom.

Case Background (2009-2021)

As a result of the gas migration investigation beginning in January 2009, DEP and Cabot entered into a Consent Order and Agreement (“2009 COA”) on November 4, 2009. That agreement was replaced by a new Consent Order and Settlement Agreement (“2010 COSA”) on December 15, 2010. Both the 2009 COA and 2010 COSA prohibited the drilling of any new gas wells by Cabot within the defined “Dimock/Carter Road Area” until certain conditions were met as established in the agreements.

In the 2010 COSA, the Department identified 18 water supplies serving 19 homes that the Department determined were affected by Cabot’s gas drilling activities in the Dimock Carter Road Area. Cabot was required to take certain actions to restore those water supplies as described in the 2010 COSA.

Following the execution of the 2010 COSA, Cabot conducted evaluation and remedial activities at some of the gas wells in the Dimock/Carter Road Area. As a result, Cabot requested to drill new wells in the Dimock/Carter Road Area. See correspondence between Cabot and the Department regarding Cabot’s compliance with the 2010 COSA here:

Department letter to Cabot (June 11, 2018) (PDF)

Cabot letter to the Department (September 14, 2018) (PDF)

Department letter to Cabot (February 8, 2019) (PDF)

Cabot letter to the Department (March 15, 2019) (PDF)

Department letter to Cabot (April 25, 2019) (PDF)

On February 8, 2019, the Department determined that six of the affected water supplies identified in the 2010 COSA had returned to background conditions or otherwise met the requirements of the 2010 COSA. See letters here: Determination Letters (February 8, 2019) (PDF).

On October 1, 2021, Cabot Oil & Gas Corporation became Coterra Energy Inc. (“Coterra”) through a merger of Cabot and Cimarex Energy Company.

2022 COA to Present

On November 29, 2022, the Department and Coterra entered into a new Consent Order and Agreement (“2022 COA”) which replaced the 2010 COSA.

Requirements of the 2022 COA:

Coterra was required to make a one-time payment of $16.29 million to the Pennsylvania Attorney General’s Office to fund the construction of a community water well system and distribution system, which will be constructed and operated by Pennsylvania American Water Company. The payment includes the connection of 19 identified impacted properties to the public water system, and a credit of $50,000 for each of those properties, which is the estimated cost to purchase water for approximately 75 years. It is expected that the public water system will be complete by December 31, 2027.
Coterra was required to offer and install interim water supply treatment systems at the identified properties within 180 days of the 2022 COA, or set aside money to do so in the future, should anyone refuse interim treatment.
Funding Notice (May 1, 2023) (PDF)
Department Approval (May 19, 2023) (PDF)
Coterra is required to submit a Long-Term Operation and Maintenance Plan if, for some reason, it is determined by the Pennsylvania Attorney General’s Office that the public water system is unable to be completed. The Long-Term Operation and Maintenance Plan will provide for operation and maintenance of the installed interim treatment for a period of 30 years.
Coterra is required to conduct quarterly wellhead screening and raw water sampling of each of the Subject Water Supplies each calendar quarter until the public water system is available, subject to landowner consent
Coterra was required to evaluate the feasibility of actions to alleviate potential gas pressure and volume in the vicinity of the Gesford 3 gas well and the Gesford 9 gas well.
Gesford Report (May 24, 2023) (PDF)
Coterra is required to plug 18 gas wells in the Dimock/Carter Road Area identified in the 2022 COA by December 31, 2032.

Upon providing written confirmation to the Department that Coterra had made the one-time payment to the Attorney General’s Office, installed interim water supply treatment systems where permission was granted, and established the mitigation fund (Confirmation Letter (May 22, 2023) (PDF)), the 2022 COA allows Coterra to submit permit applications to drill new wells and to drill, complete, and produce permitted wells from surface hole locations outside the Dimock/Carter Road Area that have horizontal wellbores that traverse under the Dimock/Carter Road Area. Such drilling and completion shall be done in accordance with Department-issued permits, the applicable laws and regulations of the Commonwealth, and an Operations Monitoring Plan as defined in the 2022 COA.

Well Permits Issued to Coterra pursuant to the 2022 COA with horizontal wellbores that traverse under the Dimock/Carter Road Area:

115-23099
ePermitting Public Review - BUSHNELL R PAD 1 OG ESCGP - 115-23099 - Approved - 7/31/2023

115-23100
ePermitting Public Review - BUSHNELL R PAD 1 OG ESCGP - 115-23100 - Approved - 7/31/2023

115-23101
ePermitting Public Review - BUSHNELL R PAD 1 OG ESCGP - 115-23101 - Approved - 7/31/2023

115-23102
ePermitting Public Review - PALKO J PAD 1 OG ESCGP - 115-23102 - Approved - 7/19/2023

115-23103
ePermitting Public Review - PALKO J PAD 1 OG ESCGP - 115-23103 - Approved - 7/19/2023

115-23104
ePermitting Public Review - PALKO J PAD 1 OG ESCGP - 115-23104 - Approved - 7/19/2023

115-23105
ePermitting Public Review - PALKO J PAD 1 OG ESCGP - 115-23105 - Approved - 7/19/2023

115-23106
ePermitting Public Review - RAYIAS, E. PAD 2 - 115-23106 - Approved - 7/19/2023pdFHandler.ashx (pa.gov) (Alternate method approval for this well)

115-23107
ePermitting Public Review - RAYIAS, E. PAD 2 - 115-23107 - Approved - 7/19/2023pdFHandler.ashx (pa.gov) (Alternate method approval for this well)

115-23108
ePermitting Public Review - RAYIAS, E. PAD 2 - 115-23108 - Approved - 7/19/2023pdFHandler.ashx (pa.gov) (Alternate method approval for this well)

115-23109
ePermitting Public Review - RAYIAS, E. PAD 2 - 115-23109 - Approved - 7/19/2023pdFHandler.ashx (pa.gov) (Alternate method approval for this well)