A crew chief for a Houston-based drilling contractor is facing up to a year in prison and a $100,000 fine for negligently violating the Clean Water Act in 2007.

Gabriel Henson pleaded guilty Wednesday to the misdemeanor charge in federal court in Muskogee, according to federal officials.

Henson had been accused of driving a pickup owned by employer Integrated Production Services through an earthen berm on May 24, 2007, allowing water contaminated with up to 700 gallons of hydrochloric acid to flow into Dry Creek in Atoka County, according to court papers.

Henson was the supervisor of a crew performing hydraulic fracturing at the Pettigrew 18-3H well owned by Antero Resources Corp.