Garfield County Air Monitoring

We received the following post from an O&G industry worker on our Facebook page:

Results coming in from air quality tests near Parachute, CO shows “little risk”…”According to the data, all air concentrations of individual and combined volatile organic compounds (VOCs) were below long-term, non-cancer health guideline values established by state and federal agencies.” But I’m sure you and ECBU will find some flaws with the tests to discount the results… Still, it is good to have more data points.

For the purposes of this discussion, let’s refer to the following documents:

Read on for some comments.

The Health Effects of VOCs

It’s correct that the CDPHE report asserts that “all air concentrations of individual and combined VOCs were below long-term non-cancer health guideline values established by state and federal agencies.” However, the EPA lists the following possible heath effects:

  • Eye, nose and throat irritation
  • Headaches, loss of coordination and nausea
  • Damage to liver, kidney and central nervous system
  • Some organics can cause cancer in animals, some are suspected or known to cause cancer in humans.

Key signs or symptoms associated with exposure to VOCs include:

  • conjunctival irritation
  • nose and throat discomfort
  • headache
  • allergic skin reaction
  • dyspnea
  • declines in serum cholinesterase levels
  • nausea
  • emesis
  • epistaxis
  • fatigue
  • dizziness

So yes, the CDPHE says that the VOC levels from this site are unlikely to cause cancer, but cancer risk is just one aspect of the risks that VOCs pose to our health. This embodies the back-and-forth between “we’ll drill because you can’t prove it’s unsafe” vs “you should only drill if you can prove it’s safe.” We’ll be able to make stronger correlations in the next 30-100 years, but assigning causality for a geriatric cancer to a childhood exposure event at a school will be impossible, especially when operators say they’re doing nothing wrong.

Ethane and Propane Concentrations

Setting the cancer discussion aside, let’s now look at ethane and propane levels in the report:

Canister 1 (Downwind) Canister 2 (Upwind)
Jul Aug Sep Jul Aug Sep
Ethane 19.55 20.45 23.05 8.45 9.80 8.00
Propane 5.97 6.20 7.13 2.55 2.93 2.57

If we look at the ratios of the downwind vs upwind samples over the three months, we see that the operation is leaking enough ethane and propane to more than double the ambient levels:

Jul Aug Sep
Ethane 2.31 2.09 2.88
Propane 2.34 2.12 2.77

This is particularly worrisome given ethane’s role in ground-based ozone production and how natural gas isn’t actually better for global warming than coal, given how much of it leaks during production and transportation.


Some “good” news, some bad news. We battle on.

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