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State detects benzene levels above health guideline in Weld County

Colorado Department of Public Health and Environment
Posted at 10:07 PM, Dec 15, 2021
and last updated 2021-12-16 00:07:33-05

DENVER — The Colorado Department of Health and Environment is investigating after the level of benzene measured at an oil and gas industry site in Weld County was higher than the health guideline last week.

The Colorado Air Monitoring Lab measured a benzene level of 9.9 parts per billion in a community north of Union Reservoir on Dec. 11, and the results were confirmed on Dec. 13. The federal Agency for Toxic Substances and Disease Registry’s short-term health-based guideline is 9 parts per billion.

Benzene is a volatile organic compound that can be released into the air from sources like vehicles, landscaping tools, cigarette smoke and household products. People are exposed to low levels of benzene daily, but exposure at higher levels can cause headaches, skin and eye irritation and respiratory issues.

The measurement in Weld County does not reflect an immediate health risk to the community, according to CDPHE, however, it does indicate the need for further testing. The health-based guidelines are set much lower than the levels that could lead to negative health impacts, CDPHE says.

The state’s new Mobile Oil/gas Optical Sensor of Emissions was sent to the community to gather more information about emissions near Cub Creek Energy’s Knight operating in Weld County. The mobile monitoring van detected the elevated benzene measurement approximately 600 feet from the operation.

The state said there is not enough information to determine the exact source of the elevated benzene level.

In more than 400 hours of monitoring the site, CDPHE says it’s the only elevated level that has occurred.

CDPHE will investigate with the assistance of the Colorado Oil and Gas Conservation Commission. This investigation will include:

  • Inspecting the Cub Creek Energy Knight operation and evaluating other potential sources nearby.
  • Continuing to measure benzene and other volatile organic compounds at the site.
  • Determining whether elevated benzene levels are occurring more frequently and notifying the public accordingly.
  • Analyzing all the data collected during the elevated measurement.

Anyone experiencing serious or persistent symptoms that may be related to benzene should contact a health care provider. Anyone with health concerns or questions about the oil and gas operations and recent measurement can contact the Oil and Gas Health Information and Response Program at (303) 389-1687 or