Air pollution from oil and gas operations is on the wane, the industry says. But communities along the Front Range — with their own air monitors — counter that they are finding repeated spikes of methane and other pollutants.
“Ground-level methane monitoring shows no decline in levels,” Cindy Copeland, an air and climate policy advisor for Boulder County, told a Colorado Air Quality Control Commission hearing Thursday.
In Broomfield, air monitors recorded a dozen spikes where ambient benzene levels were estimated to have exceeded a 9 parts per billion health standard in the fourth quarter of 2021 — in one instance the level reached 223 ppb.
Broomfield identified the peaks as coming during drilling, hydrofracturing, or fracking, and tubing wells — the so-called preproduction phase, Mindy Olkjer, the city’s oil and gas program manager told the commission.
The air commission adopted new regulations in 2020 to cut emissions from the preproduction phase of oil and gas operations.
What the spikes and eddies in emissions means for public health and safety is still undetermined.
In May, two industry groups — the Colorado Oil and Gas Association and API-Colorado — made a presentation to the air commission with data showing that between 2013 and 2019 methane levels had decreased 52% and at the monitor in Platteville operated by the state, ethane concentrations were down 65%.
The Platteville Atmospheric Observatory is about 5.5 miles southeast of Platteville, in Weld County, the most actively drilled county in the state.
On Thursday the industry groups’ findings were challenged by air quality officials from Longmont, Erie, Broomfield and Boulder County, where some of the drilling closest to neighborhoods has taken place.
The industry methane measurements were done by satellite for a large section of the Front Range, but the monitors located in communities — the Erie monitor is located next to the baseball field at the town’s community center — offer some “ground truthing,” Copeland said.
The Platteville monitor, the local air officials also argued, is no longer representative since the area has already been drilled and operators have moved to new locations.
Industry representatives pushed back.
“The anti-oil and gas politicians in Boulder and the Boulder suburbs have made clear through their political campaigns, litigation, rulemakings and more that they want to ban oil and natural gas development in Colorado,” Dan Haley, president of the Colorado Oil and Gas Association, said in a statement.
“So it’s no surprise they have found cherry picked data that supports their predetermined outcome but serves as an outlier to our industry data and the state’s data,” Haley said.
Courtney Taylor, an air quality scientist with Ramboll Group, a consultant advising Weld County, said that the local government analysis was “inaccurate and uninformed.”
Taylor said that the Platteville monitor remains representative for the Front Range area of prime drilling activity and that satellite data was state of the art. Atmospheric measurements — so called top-down surveys — can capture emissions missed on the ground.
In 2012, atmospheric measurements — from aircraft — discovered that Colorado methane emissions were being underestimated. Satellites are now increasingly being used to identify super-emitters and methane hot spots.
And while there may not be new drilling in Platteville, at least five new drill sites have been approved around the town, according to a map submitted by the four local goverments.
Still, the Colorado satellite measurements looked at the air mix happening at 10,000 feet for just three summer months and the Platteville samples are taken from 6 a.m. to 9 a.m., not the most active period for oil and gas operations, Jane Turner, Longmont’s oil and gas air quality program manager, said.
The ground monitors, local officials said, more realistically represent what the residents of their communities are exposed to from oil and gas operations. “Our residents are living close to multiple sites,” Olkjer said.
Looking at the battling data, Commissioner Curtis Reuter said, “they don’t tell the same story. I guess the truth is somewhere in the middle.”
The four communities collectively have six real-time monitors and 22 sensors periodically collecting samples, all funded through municipal and county budgets.
Broomfield’s program, which includes two real-time monitors and 12 sensors stations, costs about $1 million a year.
Both Copeland and Turner said that their monitors record methane spikes when the wind is blowing from the northeast — coming from deep in the heavily drilled DJ Basin.
And composition of the emissions reveal a chemical fingerprint linking them to oil and gas operations, Bill Hayes, Boulder County air quality coordinator, said.
Boulder’s monitor is at the Boulder Reservoir and Longmont’s is at the Union Reservoir. The Longmont site has record spikes in methane of more than 3,600 ppb, almost double the average methane concentration based on National Oceanic and Atmospheric Administration data.
These plumes may also contain ethane, butane and benzene, Detlev Helmig, principal in Boulder Air, which oversees some of the air monitoring for the four communities, said in an interview.
The granular nature of the local monitors sometimes can pick up unseen problems. In Erie, which has 400 producing oil wells in the town or within 2,000 feet of its borders, a sudden jump in total volatile organic chemicals recorded at the Kenosha Farms Station, the monitor farthest away from oil and gas operations, led to the discovery of a leaking pipeline.
The readings went to 61.9 ppb from 12.5 ppb and then dropped to 8.7 ppb after the pipeline was repaired, said David Frank, Erie’s energy and environmental program specialist.
Similarly a sudden rise in readings at two Broomfield monitors when there was a wind from southwest — an area with no oil and gas operations — led to the the discovery of a leaking gathering line, which brought out inspectors from the Colorado Public Utilities Commission.
“It was determined to not be reportable or otherwise pose a hazard to public safety,” Gail Conners, a PUC spokeswoman, said in an email.The owner was ordered to repair the line.
As for the question of health risks, the state’s Toxicology and Environmental Epidemiology Office says risk of harmful health impacts from exposures measured near oil and gas operations is low, based on available monitoring data and health risk assessments.
Once again, towns and counties are less sanguine about those risks. A health study done by Broomfield found that adults living within 1 mile of well sites report greater frequency of upper respiratory problems as well as nosebleeds and nausea than those living more than 2 miles away.
UPDATED: This story was updated at 9 a.m. on July 22, 2022, to add a comment from the Colorado Oil and Gas Association.