Data without context is detrimental
Published on May 23, 2025
by Dr. Annareli Morales, Weld County Air Quality Policy Analyst,
Weld County Department of Public Health and Environment
When the Bishop Well incident in Galeton occurred in April, my initial concern was for the potential community exposure to air toxics like benzene. As the Air Quality Policy Analyst for the Weld County Department of Public Health and Environment, air quality monitoring, modeling and data analysis is my job. So, our local health team started reviewing the initial air monitoring results shared to us by Colorado State University (CSU) and the Colorado Department of Public Health and Environment (CDPHE) from locations around the well site and confirmed those results never reached levels of health concern as set forth by the U.S. Environmental Protection Agency (EPA) for short-term exposure – good news for residents.
Recently however, the CSU and CDPHE data were reported in local news stating researchers sampled air from the plume “about one mile downwind from the well, with the highest reading of 35.5 parts per billion [ppb] of benzene at the plume’s edge … ” – that sounds like not good news for residents, but is it?
Air quality is a complex topic. Air toxics are pollutants that, at sufficient concentrations and exposure, are known or suspected to cause serious health impacts, but the impacts of these pollutants on health varies depending on how much you’re exposed to, how long the exposure and how you come into contact with it, such as breathing or through touch. That is why context is so important when discussing this topic. And that is what’s missing in the discussion prompted by local and national reporting of initial air measurements: where were the sampling locations relative to the well pad and to other sampling locations; what was the wind direction; what time of day and on which day were the samples taken; were there other sources that could have contributed to the readings? Without full context and thorough analysis to explain the data, a disservice to public health messaging occurs – not good news for anyone.
Hearing that benzene (which is emitted from gasoline, vehicle exhaust, glues, paints, furniture wax, and yes, oil and gas production) levels are high is scary. But when we compare the EPA guideline
levels to protect public health during emergency situations – which say exposure to benzene at a level of 130,000 parts per billion (ppb) for 10 minutes (or 52,000 ppb for 60 minutes) could result in mild, non-disabling health effects – to the CSU report of recording 35.5 ppb, it is a much smaller amount than what the EPA listed as a health guideline level.
The CSU measurements of benzene concentrations, as reported, never exceeded the health guideline levels for short-term exposure; in fact, none of the air quality measurements taken by responding agencies we are aware of exceeded the health guideline levels for short-term exposure to benzene.
As Colorado embarks on several upcoming Air Quality Control Commission rulemakings on Priority Air Toxics, health-based standards, and assesses the need for an air toxics permitting program, it is crucial that clear and consistent communication must be the goal. Being transparent with data is important; however, data only becomes meaningful and actionable when combined with context.
That’s why Weld County is advocating for open and transparent sharing of data as well as active discussions among all the air monitoring agencies – especially when it comes to the Bishop Well incident. Science should be neutral; numbers and data, with context, provide actionable results that benefit all of Colorado. As scientists and researchers, we all need to be on the same page about what we are seeing and what we are doing when it comes to air quality. We are all on the same team; we all want clean air; and, we all want to get to the truth. Our residents deserve nothing less.