The Wyoming Department of Environmental Quality has backed off a plan to allow Moneta Divide oilfield operators to increase pollutants they dump into creeks above Boysen Reservoir, and proposed new monitoring of existing salty effluent.

Aethon Energy and Burlington Resources will not be permitted to dump up to 8.27 million gallons a day and more than 1,000 tons each of sodium and sulfate a month into Badwater and Alkali creeks as they requested last year, according to a revised DEQ draft permit. Instead a “significantly different” plan would maintain existing discharge levels of about 2 million gallons a day.

DEQ would also require additional monitoring below the Moneta Divide oil and gas field east of Shoshoni because of a “reasonable potential” for oilfield discharges of produced water to exceed environmental standards, the revised draft permit states. New monitoring is necessary, DEQ concluded, because the average chloride content of discharged water today is about 10 times more than the environmental limit set for Badwater Creek.

The energy companies in 2019 sought the increase in pollutant flows as they proposed expanding the field from about 800 to 4,250 wells. Discharges would funnel into Badwater and Alkali Creeks, which flow into Boysen Reservoir and then the Wind and Bighorn rivers below.

Residents in Thermopolis, 15 miles downstream of Boysen Reservoir, get their drinking water from the Bighorn River. Many had questioned that 2019 plan.

DEQ received more than 450 comments on the 2019 plan, plus input at two public meetings, the agency wrote. It revised the draft permit based on those comments and on information the agency gathered during the process

“We’re glad to see they took all the public comments seriously,” said Jill Morrison, executive director of the Powder River Basin Resource Council, which challenged the proposal. “We will just have to see whether they went far enough … for protection of the streams and fisheries.”

The permit the companies sought would have authorized larger flows from the Frenchie Draw plant. The facility treats salty water from oil and gas wells, blends it with untreated water and discharges it onto the landscape. That permit, however, is no longer “practical or necessary,” DEQ said in announcing the new proposal.

That’s because the plant hasn’t worked since last March “due to technical issues,” according to the new draft DEQ permit.

“The permittee has no specific plans to re-open the treatment plant at this time,” the DEQ wrote in the draft. “An increase in discharge volume and pollutant load … is therefore not practical or necessary to permit at this time.”

Aethon’s original plan called for pollutants to be diluted in Boysen Reservoir. After mixing with other water there, outflow into the Wind River below would be within the range of normal fluctuation of pollutants, the DEQ said in its original permit analysis that would have allowed more pollution.

The U.S. Bureau of Land Management is still considering Aethon and Burlington’s plans to expand the Moneta Divide field across 327,645 acres in Fremont and Natrona counties. “Aethon Energy will continue to operate in compliance with the existing and future WDEQ permits for Moneta Divide,” Stefanie Scruggs, a vice president at the company wrote WyoFile in an email. Company officials told a radio reporter last year Aethon is in no rush to expand.

The pace of development depends on the price of natural gas, among other factors, and Aethon has no immediate plans for a large-scale drilling program, according to K2 Radio.

The new DEQ permit proposes allowing flows that would discharge 908 tons of salt a month, the historic average for the field. New monitoring requirements would limit the concentration of salt as well, the draft permit states.

Badwater Creek, into which the produced water flows, is protected by standards that allow no more than 230 mg/L of chloride, according to the DEQ. “A review of the long term effluent data from this [Frenchie Draw] facility indicates that the average chloride concentration at the outfalls is around 2,200 mg/L,” the DEQ draft permit states.

The new draft plan sets a limit of 230 mg/L for chloride in discharged water, a limit that wasn’t included on previous permits. Operators, however, won’t have to comply with the new levels until July 1, 2024.

The delay would allow the energy companies time to install additional treatment capacity at its defunct plant and allow the state to reconsider its protection standards for Badwater Creek.

Laws and regulations protect Badwater Creek flows for drinking, fish, other aquatic life, recreation, industry, wildlife, agriculture and scenic values. Protections are less stringent for Alkali Creek. Drinking water and fish are not on its list of values.

Regulators last year began sampling the two creeks with an eye toward reclassifying them to allow more pollutants.

“If the chloride standard on Badwater Creek is revised prior to the final compliance schedule deadline [in the proposed new permit] of July 1, 2024, then the final effluent limit for chloride in this permit will be modified accordingly,” DEQ wrote.

DEQ has set a 30-day comment period for the new draft permit, which was officially released Jan. 17. Citing public interest and the complex topic, a number of organizations are asking for more time.

“The multitude of factors that led you to extend the comment period and hold hearings on the first draft still exist,” the Powder River Basin Resource Council and five other conservation groups wrote the DEQ. “[I]f anything, public interest in the project and its potential impacts to Boysen Reservoir has continued to mount, and the complexities and issues raised during the initial comment period remain, and are without question daunting.”

Even as it considers comments on the new permit, DEQ should further investigate existing flows, the PRBRC told the agency in another letter dated Jan. 17, 2020 (see below). Water samples from oilfield discharge channels and creeks showed the presence of dangerous volatile compounds, the resource council wrote. It based its claim on documents the group and the Wyoming Outdoor Council obtained through records requests.

As the DEQ continues to sample Badwater and Alkali creeks, it is not checking for a certain classification of compounds like benzene, toluene, ethylbenzene and xylene, the PRBRC wrote the DEQ.

It’s extremely important to test for these compounds, PRBRC wrote in its letter, “given the adverse environmental and health effects of these pollutants.” The DEQ should set limits for them in the new permit, the group wrote.

Oilfield operators also violated the existing permit’s effluent levels 15 times between 2015 and 2019, PRBRC wrote. The watchdog group listed violations of standards limiting iron, zinc, oil, grease and pH. In one case, a sample showed oil and grease at 289% the allowable limit, the group wrote.

Despite the apparent violations, the DEQ took no action to bring operators into compliance, PRBRC’s Morrison said. “We’re wondering where is the enforcement from the DEQ,” she said.

DEQ officials were not available on Monday, a holiday, to respond.

An expanded Moneta Divide field would produce about 18.16 trillion cubic feet of natural gas and 254 million barrels of oil over 65 years, the BLM has said. Development could bring $71 million a year in federal royalties, $57.6 million a year in Wyoming severance taxes and $70 million a year in county ad valorem taxes.

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