State: Hydrogen sulfide gas found at near-fatal levels south of Parachute
Post Independent Staff
Glenwood Springs, CO Colorado
RIFLE, Colorado – State regulators confirmed in a public meeting on Thursday that near-fatal levels of hydrogen sulfide gas were detected at a Noble Energy drilling pad earlier this year.
A report from the Colorado Oil and Gas Conservation Commission (COGCC) revealed that hydrogen sulfide had been detected at levels of up to 450 parts per million at four separate well pads south of Parachute.
The gas is considered lethal at 500 parts per million, and can cause sickness, respiratory distress and irritation of the eyes at lesser levels, according to the U.S. Centers for Disease Control and other sources.
None of those wells are venting hydrogen sulfide gas, or H2S, into the atmosphere, said Stuart Ellsworth, engineering manager for the COGCC.
Ellsworth’s remarks were intended to assure the public that there is no public health risk from the presence of H2S in the Piceance Basin gas fields.
He also reported that the closest occupied structure to any of the four wells is 980 feet away. COGCC data indicates the gas would not spread beyond a 60-foot radius from its source.
Ellsworth’s remarks came during a presentation at the Northwest Colorado Oil and Gas Forum held at Colorado Mountain College in Rifle, in which he reported on a COGCC investigation into H2S encountered at Noble well pads beginning in 2009.
In March 2009, Noble notified the state regulatory agency that it had found H2S at 312 of its 353 gas wells in the area south of Parachute.
But those reports indicated only that the gas had been encountered at levels of either less than 10 parts per million or more than 10 parts per million, as COGCC Executive Director David Neslin and Ellsworth told the Post Independent in early August.
Neslin and Ellsworth researched Noble’s reports in response to allegations from a former gas industry worker, Carl McWilliams of Silt Mesa, that he was poisoned by H2S while working on a Noble gas pad in 2009.
Further investigation by the COGCC, Neslin said on Aug. 26, showed that “Noble has reported hydrogen sulfide in the neighborhood of 100 parts per million,” a level that is considered hazardous enough that federal and state regulators require companies to have a special operations plan to deal with the gas.
At that level of exposure, according to Ellsworth’s public presentation on Thursday, humans experience coughing, eye irritation and loss of the sense of smell after 15 minutes or more.
If the exposure continues at 100 ppm for several hours, Ellsworth reported, “death may occur within the next 48 hours.”
According to Ellsworth, tests at four well pads south of Parachute, two on March 12, one on March 16 and one on April 5 of this year, showed H2S levels at 100, 170, 200 and 450 ppm at the different wells.
Noble, according to Ellsworth and the company’s Rocky Mountain business manager, Bob Ovitz, has long had a safety plan in place to protect its workers from hydrogen sulfide gas.
But at least one former well-services worker has accused to company of not having such a plan when he was on the rigs.
McWilliams, who worked for a contractor called Lonkar Services US (operating locally as Lightning Wireline of Rifle), has said he was poisoned by exposure to hydrogen sulfide at a Noble well pad south of Parachute in February and March of 2009.
The federal Occupational Safety and Health Administration backed him up in August of 2009, citing Lonkar for violating worker safety guidelines and not providing adequate training for its workers.
McWilliams has said that he and a partner, Troy Orth, were operating a “workover rig” on a production well in late February and early March of that year, when they were exposed to H2S as concentrations of between 60 ppm and 100 ppm.
McWilliams suffered severe double vision and what he called “stroke-like symptoms” in the days following the Feb. 27, 2009 exposure.
Orth died on March 10, 2011, and McWilliams maintains Orth’s death was a consequence of exposure to H2S during the same period.
The Garfield County Coroner’s Office ruled that the cause of death was a heart attack, but Orth’s widow, Kim Orth, has said publicly that she now feels that may not be true.
Start a dialogue, stay on topic and be civil.
If you don't follow the rules, your comment may be deleted.
After bowing out of the 3A state soccer playoffs in the quarterfinals and semifinals the past two seasons, the Roaring Fork Rams finally get their shot at a state title on Saturday.