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Enforcement

MarkWest Clean Air Act Settlement Information Sheet

WASHINGTON – The Department of Justice, the U.S. Environmental Protection Agency, and the Pennsylvania Department of Environmental Protection announced a settlement today with MarkWest Liberty Midstream Resources, LLC and Ohio Gathering Company, LLC (MarkWest), which is expected to reduce emissions of volatile organic compounds (“VOCs”) by more than 700 tons per year from company facilities in eastern Ohio and western Pennsylvania. The settlement addresses alleged violations of the Clean Air Act and the Pennsylvania Air Pollution Control Act for failure to obtain permits and keep records associated with maintenance activities that resulted in VOC emissions. As part of the settlement, MarkWest will also perform three supplemental environmental projects (“SEPs”) and pay a $610,000 civil penalty.

Overview of Company

MarkWest Liberty Midstream & Resources, LLC and Ohio Gathering Company, LLC are subsidiaries of MarkWest Energy Partners (collectively, MarkWest), which is headquartered in Denver, Colorado. MarkWest is a subsidiary of MPLX LP, headquartered in Findlay, Ohio.

MarkWest and MPLX LP are engaged in the gathering, transportation, and processing of natural gas, the transportation, fractionation, marketing, and storage of natural gas liquids, and the gathering and transportation of crude oil. MarkWest has natural gas operations in the southwest, the Gulf Coast, and the northeast regions of the United States, including the Marcellus and Utica Shale formations. MarkWest provides midstream services in natural gas resource operations, provides services between upstream exploration and production of natural gas, and delivers hydrocarbon products to intermediate or end-use markets, in natural gas resource operations.

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Violations

The United States and the Pennsylvania Department of Environmental Protection (“PADEP”) have filed a complaint against MarkWest for violations of the Clean Air Act and the Pennsylvania Air Pollution Control Act at MarkWest compressor stations and stand-alone pigging facilities in western Pennsylvania and eastern Ohio.

“Pigging operations” are maintenance activities that are performed on a daily, weekly or monthly basis to prevent buildup of natural gas condensates in field gas gathering and transmission pipelines. These operations require a facility to vent and blowdown any pressure in the line prior to removing the device known as a pig used for the maintenance activities, including cleaning the interior of the pipeline from buildup of liquids.

MarkWest failed to apply for, and comply with, the required permits and/or recordkeeping requirements under the Nonattainment New Source Review, Prevention of Significant Deterioration and Title V programs, and the Pennsylvania and Ohio State Implementation Plans, for natural gas pigging and venting activities that released excess VOC emissions.

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Injunctive Relief

MarkWest has agreed to the following elements of injunctive relief for compressor stations (26 facilities) and large stand-alone sources (19 facilities) in the Ohio and Pennsylvania natural gas gathering system: (1) connection of high pressure pig launchers and receivers by jumper lines to a low pressure gathering line; (2) operation of jumper lines to depressurize such launchers and receivers prior to opening the launcher or receiver hatch; (3) installation and use of pig ramps in pig receivers; (4) use of a flare to control VOC emissions, when necessary, to ensure that VOC emissions do not exceed the state permitting threshold or permitted emissions limitations; and (5) submission of non-Title V state-only operating permits, or non-Title V Permits to Install and Operate, that are federally enforceable and will survive termination of the Consent Decree. There are some variations from these requirements at individual facilities. MarkWest will also cease operations at all launchers and receivers at the Drugmand and Stewart Route 50 Stations, and all high pressure launchers and receivers at the Graham Header Station. To resolve violations of the small stand-alone sites (273 facilities) in Ohio and Pennsylvania, MarkWest has agreed to install pig ramps in all pig receivers. The injunctive relief under this settlement is valued at approximately $2.6 million.

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Pollutant Impacts

When fully implemented, EPA estimates that the new controls and requirements would result in emission reductions of 706 tons per year (tpy) of Volatile Organic Compounds (VOCs), and 91.5% annual emission reductions throughout the natural gas gathering system.

This case and settlement is the first to recognize and address the significant noncompliant VOC emissions associated with pigging and maintenance operations in wet gas shale plays, such as the Marcellus and Utica formations.

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Health and Environmental Benefits

VOCs contribute to smog and to sensory irritation symptoms, allergies and asthma, and neurological and liver toxicity. Certain VOCs are also known carcinogens. Through the installation of air pollution controls at over 300 facilities, MarkWest will improve the air quality in western Pennsylvania and eastern Ohio.

As a condition of settlement, MarkWest has agreed to install and operate ambient air monitoring stations near two compressor stations in Pennsylvania and Ohio.  Information gathered about the nature and extent of VOC emissions from midstream oil and gas operations will be shared with the public. In addition, MarkWest will make available royalty-free licenses to use their proprietary pig ramp technologies developed during the enforcement investigation, and share methods for controlling emissions from pigging operations with industry.

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Civil Penalty

The proposed decree requires Defendants to pay a $610,000 civil penalty.

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Comment Period

The proposed settlement, lodged in the U.S. District Court for the Western District of Pennsylvania, is subject to a 30-day public comment period and final court approval.  Information on submitting comment is available at the Department of Justice website.  

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Contact Information

Christopher Williams (Chemical Engineer)
EPA Office of Civil Enforcement, Air Enforcement Division
U. S. Environmental Protection Agency
1200 Pennsylvania Avenue NW, Mail Code 2242 A, Washington D.C. 20460
(202) 564-7889
williams.christopher@epa.gov

Kathryn Caballero (Senior Attorney)
EPA Office of Civil Enforcement, Air Enforcement Division
U. S. Environmental Protection Agency
1200 Pennsylvania Avenue NW, Mail Code 2242 A, Washington D.C. 20460
(202) 564-1849
caballero.kathryn@epa.gov

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