The Montana Department of Transportation is failing to pay its fair share for an ongoing environmental cleanup, and, in the process, violating Montanans' right to a clean and healthful environment, a lawsuit by natural gas company ExxonMobil alleges.

Cleanup on an east Billings site contaminated by petroleum spills from activity decades ago began in 2011. During the past 15 years, the lawsuit states, Exxon has exclusively paid more than $10 million for the cleanup on property that once housed a Yale Oil refinery. According to the case filed in Yellowstone County District Court on Sept. 9, Exxon believes the Montana Department of Transportation should be responsible for some of the cleanup costs.

The site, which is southwest of MetraPark, is bordered by the Yellowstone River, commercial properties and the railroad. The Yale Oil refinery closed in 1949 and its property was sold to others. Yale Oil ultimately became part of Exxon.

The Montana Department of Transportation has owned and operated on a portion of the site for decades since then, the lawsuit states. The land is currently estimated to be used for gravel storage, equipment maintenance and forming the bases for roads, involving mixing petroleum and gravel piles.

In the 1980s, the Environmental Protection Agency made the location a Superfund site. Petroleum in water and soil can lead to adverse health effects like cancer and liver damage. A ditch running through the property contributes water to the Yellowstone River.

Exxon's lawsuit also suggests MDT might be responsible for some of the contamination at the site. In the 1970s and the 1990s, the lawsuit alleges, the Montana agency removed multiple storage tanks on some of the state-owned land. At the time, water was leaking into the tanks. For other tanks, gasoline and diesel fuel leaked out into the environment from them.

In 1991, another agency reported an open trench on the MDT land reeked of gasoline and was leaking petroleum material. Groundwater testing found petroleum in the water exceeded safe amounts. Lockwood, further east, used to tap into nearby portions of the Yellowstone River at the time.

In 2011, the Montana Department of Environmental Quality identified Exxon as potentially responsible for a petroleum spill that happened on the site decades ago, since they were now the owner of Yale Oil. MDT was also included in the list of potential responsible people and organizations.

In 2014, asbestos and debris were removed from and around a building on the land owned by MDT, alongside topsoil surrounding the property. Furthermore, there is currently monthly removal of residual petroleum on the property, Exxon stated.

Exxon further alleges that MDT failed to properly prevent contamination and manage asbestos-containing materials. Additionally, the state agency missed multiple deadlines set by the Montana Department of Environmental Quality, failed to comply with work plans for the cleanup and interfered with other DEQ-required work at the site. Interference included obstructing monitoring wheels, disturbing contaminated soils and filling in excavations without DEQ approval, the lawsuit stated.

MDT declined to comment because of the ongoing litigation.

Despite being identified as a responsible party, MDT hasn’t participated in funding response actions at the contaminated Superfund site, the lawsuit alleges.

This leaves Exxon picking up a disproportionate share of the costs, the multibillion-dollar company said. The oil company also alleged the state agency violated Montanans’ constitutional right to a “clean and healthful environment in Montana for present and future generations.”

“MDT has violated this constitutional duty by owning and operating the MDT tract for approximately 90 years without remediating contamination on its property and failing to participate in the funding of investigations and response actions at the site,” wrote Michael Manning, an attorney for Exxon.

The company concluded by saying MDT unjustly benefited from Exxon’s cleanup actions and Yellowstone County District Court should order that the state agency pay compensation to Exxon for the ongoing cleanup.

Present-day uses of the contaminated land after the refinery operations ceased include auto sales, warehouse storage, broadcasting company offices and road material fabrication.

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