PA Environment Digest Blog: DEP: MarkWest Liberty Midstream Reports 69,000 Gallon Pipeline Construction Fluid Loss Into Mine Voids Under Washington County; 476,600 Gallons Lost So Far

On December 13, the Department of Environmental Protection was notified by MarkWest Liberty Midstream & Resources LLC that horizontal drilling operations on the construction of the shale gas-related Chiarelli to Imperial pipeline resulted in a 69,000 gallon loss of drilling fluids into coal mine voids under Mount Pleasant Township, Washington County.

Click Here for notification.

This was the eighth reported incident bringing the total amount of fluids lost into the voids to at least 476,000 gallons on this drilling project.

DEP did an onsite inspection of the construction site on December 15, however, the site was shut down due to weather conditions and snow cover.

DEP said no fluid returns were observed on the surface along the path of the drilling or at the abandoned mine discharge point nearest the drilling. DEP inspection report & photos.

Based on the December 15 inspection, DEP said “violations may be forthcoming pending further investigation.” Read more here.

Also on December 15, MarkWest Liberty responded to a series of questions DEP asked about the incident, including the total amount of fluid lost to date. Read more here.

As part of its investigation of the last fluid loss incident on December 4, DEP staff from the Oil and Gas Program and the Bureau of Abandoned Mine Reclamation took water samples at a variety of points along the drilling route and of the drilling fluid itself. Read more here.

Report Violations

To report oil and gas violations or any environmental emergency or complaint, visit DEP’s Environmental Complaint webpage.

Text photos and the location of abandoned wells to 717-788-8990.

Check These Resources

Visit DEP’s Compliance Reporting Database and Inspection Reports Viewer webpages to search their compliance records by date and owner.

Sign up for DEP’s eNOTICE service which sends you information on oil and gas and other permits submitted to DEP for review in your community.

Use DEP’s Oil and Gas Mapping Tool to find if there are oil and gas wells near or on your property and to find wells using latitude and longitude on well inspection reports.

[Note: If you believe your company was listed in error, contact DEP’s Oil and Gas Program.]

[Note: These may not be all the NOVs issued to oil and gas companies during this time period. Additional inspection reports may be added to DEP’s Oil and Gas Compliance Database.]

PA Oil & Gas Industry Public Notice Dashboards:

-- PA Oil & Gas Weekly Compliance Dashboard - Dec. 13 to 19 -- Shale Gas Abandoned Well Violations Hit 70; Conventional Well Not Plugged For 2,045 Days; MarkWest Loses Another 69,000 Of Pipeline Drilling Fluid To Mine Voids [PaEN]

-- DEP: MarkWest Liberty Midstream Reports 69,000 Gallon Pipeline Construction Fluid Loss Into Mine Voids Under Washington County; 476,600 Gallons Lost So Far [PaEN]

-- PA Oil & Gas Industrial Facilities: Permit Notices, Opportunities To Comment - December 20 [PaEN]

-- Susquehanna River Basin Commission Approves 3 Shale Gas Water Withdrawal Requests; 22 Total For 2025 [PaEN]

-- Susquehanna River Basin Commission Approved 31 Shale Gas Well Pad Water Use General Permits In November; 429 In 2025 [PaEN]

-- DEP Posted 51 Pages Of Permit-Related Notices In December 20 PA Bulletin [PaEN]

-- DEP Invites Comments On Renewal Of The NPDES Wastewater Permit For The BET Associates IV, LLC Anthracite Mining Discharge In Schuylkill, Carbon Counties Affecting 7,479 Acres [PaEN]