
If you don’t travel to the north side of Broomfield often, you may not even know about the drilling. But if you have traveled on the Northwest Parkway going east or traveled 160th between Sheridan and Huron, you’ve seen the tall, sand-brown sound walls of the Northwest A&B pads, the United Pad, and the Interchange pads. You may have mentally noted the unobstructed proximity to Prospect Ridge Academy, a K-12 charter school, or the Anthem Lake recreation space. You may have even seen the drill rig towering not far from our Nordstrom Open Space, which is now littered with PIG launchers and other industrial-looking pipes and plumbing.
The second round of drilling in Broomfield started at around 6:30 am on 9/14/2021. (For argument’s sake, we’re calling the first round the Livingston and the initial Interchange wells, drilled before Extraction’s bankruptcy announcement.) Local Adams County residents immediately noted strong odors of petroleum, which were alluded to on several Facebook pages. It was reminiscent of 2019 when Extraction drilled the first wells at the Interchange pad and local residents wrote in and spoke at CCOB meetings time and time again, describing a strong petroleum odor that often left them gasping for air. That foul odor ended up being a by-product of the Gibson drilling mud that Extraction was using, and once a significant number of residents near the Livingston pad complained of a similar smell during that drilling process, the mud was changed to Neoflo. Gibson mud is known for its high levels of the cancer-causing VOC (Volatile Organic Compound) called Benzene, which is classified as a “known” human carcinogen (Category A) under the Risk Assessment Guidelines of 1986. Broomfield inspectors have confirmed that Extraction is using Neoflo during the second round of drilling.
But surely we have learned from 2019, right? Broomfield has since spent over $1 million on air quality monitoring systems that track these VOCs and report them in real time. They have instituted a reporting system that allows them to collect feedback about health and other concerns from the community. Extraction has gone bankrupt, reorganized, and somehow been welcomed back into our community. What could possibly go wrong?

But we can’t learn from what we don’t know: we didn’t have the air quality monitoring programs in place when Extraction was drilling the first 8 wells at the Interchange B pad and the Livingston pad in 2019– a multi-well pad located next to a retirement community and several family-centered neighborhoods (Anthem, Anthem Ranch, and Wildgrass to name a few) in northern Broomfield. Air quality monitoring data has only gone live and been producing reports since 2/2020, well after the initial drilling was done at Interchange and Livingston.
Since Extraction/ Civitas has returned, as of the start of drilling on 9/14/2021, there have been a total of 40 air quality monitor triggers in about 45 days. This is an average of one trigger a day. As a comparison, there were only 37 total triggers in the entire YEAR between the start of the tracking in 2/2020 and 3/2021. And in the five months before Extraction began drilling (3/2021- 8/2021), there were a total of 9 triggers. This number of recent triggers is unprecedented in the history of Broomfield’s air quality monitoring program.
The general process for a trigger canister is that the air quality monitoring system detects an elevated level of VOCs and triggers a “canister,” which is exactly what it sounds like : a metal collection mechanism that captures a “snapshot” of the air at the time of trigger. Scientists analyze these canister samples to give an accurate representation of these spikes, usually delivering reports that detail the most worrisome of chemicals like Benzene and Toluene and other BTEX chemicals. These reports are posted on the Broomfield City and County trigger matrix so that local residents can have insight into what is in their air. Usually, turnaround time for these canisters is about two weeks, but because of the overwhelming and unprecedented number of triggers, there is about a one month backlog in the reports. The most recent report as of the time this article was written was the report from the trigger event on 10/8/2021, nearly one month ago.
There are a few major concerns with this reality. The first is the trigger canister results: on both the 9/17 and 9/18 events, acute Benzene levels registered at 13.69 ppb and 14.22 ppb respectively. The canister analysis from 9/20/2021 registered 1-minute Benzene levels at 21.257 ppb, These Benzene levels are exponentially higher than background levels, and according to several health resources, these levels of benzene have the potential to be harmful to community members. According to a Boulder County Public Health document about Benzene (https://assets.bouldercounty.org/wp-content/uploads/2018/02/benzene-health-impacts-monitoring.pdf), 9 ppb is the threshold below which is considered “non-cancer health risk”. Levels above 9 ppb can have significant health impacts. The EPA Cancer Risk Standards from this same document identify that “There is a 1 in 10,000 lifetime cancer risk with benzene concentrations from 4 ppb to 14 ppb. This level of exposure will result in 1 additional incidence of cancer in 10,000 people. The EPA considers this risk level to be unacceptable.”
Tracking with these extreme Benzene levels is the most recent report released on October 26th about an air quality event on October 6th, which we wrote about in a recent article in which we say, “The Air Quality System detected levels of benzene 13.4x higher than recommended health guidelines. This report shows an estimated one-hour average of benzene during this event was 120.48 ppb. For context, the acute health guidelines used by Broomfield is 9ppb for a 1-hour exposure. This information was released almost three weeks after the incident date and is the largest concentration of benzene recorded by Broomfield’s air monitoring system to date.”
During an Oil and Gas community meeting on 11/3/2021, scientist Detlev Helmig hypothesized that for every one chemical spike these monitors record, at least 30 are missing the monitors, floating round our neighborhoods, unaccounted for. We are only capturing and analyzing 3% of the data.
Which brings us to our second concern: these chemicals have often been characterized as traveling in “plumes” that contain very concentrated levels of these highly toxic chemicals. It’s unknown what the impacts of the combination of these chemicals (often called chemical cocktails) and the high level of multiple chemicals may have. For example, Toluene is another dangerous chemical whose exposure has been linked to chronic nosebleeds and other health impacts. What does a Toluene and Benzene spike or plume mean for nearby children on playgrounds or senior citizens in nearby recreation spaces? These impacts, both short-term and long-term, are unknown at the moment. The theory is that these chemicals tend to not immediately dissipate, and can theoretically travel up to a mile or two in these highly-concentrated formations. A notation on the trigger canister report from United 02 on 9/18/21 mentions the presence of such a plume: “
The Apis system at United 02 triggered at 8:20 AM on 9/18. There were a series of elevated
TVOC levels in the 400 mV to 800 mV range over a 1 hour period. Following the event at 8:20
am, a new canister was installed and the system then again triggered around 10:00 AM, likely
capturing compounds of the same meandering plume. A third triggering event occurred at
11:25 pm with a TVOC Indicator reading of 329 mV, just over the 300 mV trigger threshold.”
What we are seeing is a pattern of dangerous toxicity levels confirmed by scientists.
Broomfield does have regular bi-weekly meetings to discuss these oil-and-gas-related concerns, and residents are always welcome to come ask questions and give feedback. You can also register health complaints, general complaints, or questions with the City/ County of Broomfield. If you are noticing changes in your health or your family members’ health, like sore or irritated throats, sore or irritated eyes, more frequent migraines, chronic nosebleeds, or other unusual health impacts, please register a complaint with the CDPHE (Colorado Department of Public Health and Environment) as well as with the city .
In response to a question from Councilmember Jean Lim about whether local residents can be warned about potential upcoming air quality events like Benzene spikes based on patterns related to certain pad activities, the city staff responded with the following answer: “The air quality monitoring program provides real-time air quality data on the Boulder Air and Ajax webpages. An event that triggers a canister doesn’t mean a health guidance value or air quality standard has been exceeded. In addition, as shown in the preliminary and final reports that have been completed through October 2, all of the 1-hour benzene levels were below the 9 ppb health guidance level except for one trigger event on October 1 at Northwest Parkway 2. All trigger canisters capture a point in time observation and the various constituents that make up their contents when the canisters are triggered cannot be differentiated or quantified on a real time basis. Residents can monitor the data on the Boulder Air and Ajax webpages and make their own decisions to stay indoors, close windows or take other precautions.”
What are described as “Daily Data Snapshots” on the Broomfield Oil and Gas page have intermittently been posted (though not daily) that detail much of the oil and gas activity happening in Broomfield. Only 8 snapshots have been posted during the month of October despite the increased trigger canister activity and apparent air quality triggers. The most recent was posted on 11/2/2021.