
On 7/29/2022, a Benzene plume on Extraction’s United mega-fracking pad measuring 2518.753 ppb was captured in a canister analysis provided by Ajax Analytics and CSU. As a gauge, 9 ppb is the federal, short-term Minimum Risk Level (MRL) for benzene and has frequently been cited by Broomfield Staff as a threshold for concern. Though canister analysis reports are usually finalized and published as a Broomfield report within a few days of the Ajax report, Broomfield staff members have still not published the 7/29/ 2022 report, now 12 days after the report was finalized by Ajax on 8/4/2022.
Benzene is a known human carcinogen, and according to the ATSDR (Agency for Toxic Substances and Disease Registry), “Benzene causes problems in the blood. People who breathe benzene for long periods may experience harmful effects in the tissues that form blood cells, especially the bone marrow. These effects can disrupt normal blood production and cause a decrease in important blood components. A decrease in red blood cells can lead to anemia. Reduction in other components in the blood can cause excessive bleeding. Blood production may return to normal after exposure to benzene stops. Excessive exposure to benzene can be harmful to the immune system, increasing the chance for infection and perhaps lowering the body’s defense against cancer.” The ATSDR also cites Leukemia and damage to the reproductive organs as possible effects of long-term exposure to Benzene. The World Health Organization is far more conservative and claims that “Benzene is carcinogenic to humans and no safe level of exposure can be recommended.”

Exposure to high concentrations of Benzene results in headaches, dizziness, drowsiness, confusion, tremors, and loss of consciousness. Lower levels of exposure show as eye, throat, and skin irritation.
Including this extremely high benzene plume that was measured at 2518.753 ppb, there have been 8 United pad triggers in the past 2 weeks. According to a comment submitted to the dashboard by Council member Jean Lim, a majority of these exceedances have occurred outside of normal inspection hours. Council member Lim continues to ask questions and track information about these spikes.
In the 8/12/2022 Oil and Gas Snapshot provided by the City and County of Broomfield, the staff communicated some steps they are taking to escalate the issue with the CDPHE: “In the 8/11 oil and gas coordination meeting with the CDPHE, staff reiterated our desire for deployment of air quality monitoring resources in response to the July 29 air quality events at the United pad. CDPHE indicated this could be a possibility pending further data and investigation of those events. CDPHE also shared that a preliminary process has begun to create a statewide formal data reporting structure. Discussions with the Air Pollution Control Division and the operator’s air quality team are pending.”
Concerned citizens, including those who live close to the pad, are wondering how a “closed-loop system” can result in such dangerously high levels of carcinogenic benzene exposure. Citizens in other parts of Broomfield are also concerned, as Benzene and other toxic fracking chemicals travel in “plumes,” or chemical clouds that often contain highly concentrated chemical signatures that do not necessarily dissipate at the same rate as other chemical clouds. There is scientific documentation of these plumes traveling miles and retaining their high chemical concentration, so these plumes could easily travel to parks, schools, and well into densely populated neighborhoods throughout Broomfield. Simply put, these plumes could bring densely concentrated carcinogens miles away from fracking pads, widely impacting the health and safety of our community members.
One anonymous local citizen with whom I spoke questioned why the CDPHE met with and showed (albeit minimal) concern about the 186.479 ppb Benzene spike on 12/4/2021. Questions about whether or not the CDPHE considers the Ajax data to be accurate and/or actionable seem to be floating to the surface.
Council member Laurie Anderson also submitted a comment to the dashboard, expressing her curiosity about the unprecedentedly high levels of benzene and why the state agencies aren’t considering this a problem: “This 1-hour benzene estimate of 2519 ppb is 280x the federal Agency for Toxic Substances and Disease Registry’s (ATSDR) short-term health-based guideline of 9 ppb. I realize the CDPHE prefers to focus on longer term exposures than the 1-hour estimate. However, if this 2519 ppb were averaged out over several days, the average would have been 9 ppb for 11.7 days. [2518.75 ppb ÷ 9 ppb = 279.9 hours = 11.7 days]. That is crude math but worth exploring, if the CDPHE needs to look at longer durations. While the CDPHE investigates the benzene level of 9.9 ppb in a community north of Union Reservoir which was captured by the moose , I would certainly hope they would trust the CSU summa canister analysis which was 653.40 ppb benzene and begin an investigation. Additionally, if the CDPHE desires longer duration captures, it would be helpful if they could include information on the current available technology and that a stationary monitor can only capture the plume when it travels over it in the 3D spatial realm – winds must be heading in the direction of the sensor, but also height of the plume matters. As 7 more United triggers have continued since the 7/29 benzene level of 2519 ppb, these conversations become more urgent as we wait for canister analysis. I look forward to a robust discussion as we determine how to address these spikes of benzene magnitudes above the health-based guideline, and whether the CDPHE has authority to set enforceable limits on HAPs – especially with HB20-1244. Or if, in the absence of state limits, Broomfield has this authority.”
The triggers for the last weeks are as follows:
– 8/16 1:24 United 02
https://trello.com/c/Bg9W9Y16
-8/16 1: 26 United 03
https://trello.com/c/GZZrB802
– 8/15 16:49 United 01
https://trello.com/c/31dIP7bW
– 8/15 4:45 United 01
https://trello.com/c/HtLxVsbK
– 8/9 4:11 United 01
https://trello.com/c/kx8Asthv
– 8/6 19:06 United 01
https://trello.com/c/j0YKiLVZ
– 7/29 1:16 United 02, benzene level 2519 ppb
https://trello.com/c/4UDPvkjd
– 7/29 01:16 United 03, benzene level 2447 ppb
https://trello.com/c/bXzZJj1L
If exposing yourself and your family to carcinogenic chemicals is concerning to you, please reach out to your respective council person.