HUGHESVILLE – The state Attorney General’s Office has charged an energy company with allegedly dumping more than 50,000 gallons of natural gas drilling waste water onto the ground and into a tributary from the Marquardt well site in Penn Township.

XTO Energy, based in Indiana, Pa., has been charged with three counts of unlawful conduct under the Solid Waste Management Act, and five counts under the Clean Streams Law, according to Attorney General Kathleen Kane.

A subsidiary of ExxonMobil, XTO is alleged to have dumped upwards of 57,000 gallons of waste water onto the ground into an unnamed tributary of Sugar Run sometime between early October and mid-November 2010, according to seven-page affidavit.

The alleged violations were discovered by a water quality specialist with the state Department of Environmental Protection during an unannounced inspection held on Nov. 16, 2010, according to a grand jury.

The Marquardt well site is comprised of two natural gas wells. During production, the wells release toxic waste water that contains substances such as chlorides, barium, strontium and aluminum. Also located at the site were 49 mobile tanks used to store this waste water. Each tank held about 21,000 gallons, according to the affidavit.

On Nov. 4, 2010, XTO hired a company to recycle the waste water at the Marquardt site. However, XTO told the company to move its equipment to another well site in West Virginia on Nov. 11.

Between Nov. 12 and Nov. 16, about 94,000 gallons of waste water were transported to the Marquardt site, although no recycling occurred then, a grand jury found.

Six of the tanks allegedly were connected by a manifold system installed into the front of the tanks, which allowed waste water to flow between them, and essentially turned the group of tanks into one large reservoir. According to testimony, the system was installed some time around Nov. 16, 2010.

The DEP inspector found that the rear drain plugs on six of the tanks had been removed on many of the tanks. Investigators estimate that about 57,000 gallons of the 94,000 gallons of water transported to the site leaked out of the tanks and onto the ground.

When the investigator returned to the site the next day on Nov. 17, he noticed dead vegetation behind several of the tanks, which he had not noticed before. These plants were “was likely killed by chlorides in the discharged waste water,” according to the affidavit.

Shortly after the suspected leak, samples of an unnamed tributary to Sugar Run were collected and analyzed. The water contained elevated levels of chlorides, barium, aluminum and total dissolved solids, according to court records. Repeated testing of the water revealed the pollution was present until March 9, 2011, records state.

The discharged waste water necessitated the excavation and removal of about 3,100 tons of contaminated soil. The excavation process began on Nov. 19, 2010 and lasted until Feb. 8, 2011.

No spill containment system was installed under any of XTO’s tanks at the Marquardt site. The rear valves of the tanks could not be locked, the grand jury found. The company also allegedly failed to place a fence around the site or install guards, alarms, surveillance cameras or any other security measures, records state.

In a statement to the media, XTO called the charges “unwarranted and legally baseless.”

The statement went on to say that “neither XTO nor any of its employees intentionally, recklessly or negligently discharged produced water on the site.”

XTO said it “would challenge the criminal charges,” and that the company “acted quickly and cooperatively with state and federal authorities to clean up the produced water. There was no lasting environmental impact and the site has been fully remediated in according with DEP.”

A preliminary hearing has been scheduled before District Judge Jon E. Kemp.

Philip A. Holmes/Sun-Gazette staff contributed to this story.