Extraction’s Response on Drilling Mud Leaves Unanswered Questions

In a June 5 written response to City Staff, Extraction claimed that Gibson D822 drilling mud being used at its Interchange B Pad since April 18 “hasn’t been correlated to any instance of odor.”  This completely contradicted the fact that Extraction added odor neutralizer Benzaco Odor-Armor and a second mud chiller to be used at the site.  Extraction’s action was after a Colorado Oil and Gas Conservation Commission (COGCC) inspector smelled the odor of the drilling mud on May 13 and ordered corrective action be taken by Extraction.  Additionally, questions about the drilling mud’s carcinogenic components remain unanswered as drilling continues on Interchange B and the use of this drilling mud is scheduled to begin on the Livingston Pad by about mid-July. 

It has been almost a month since residents living near the Interchange B Pad stood in Council Chambers to report both short-term health impacts and long-term questions about the odorous, carcinogenic drilling mud Gibson D822 that Extraction has been using to drill there since April 18.  At that May 14 Council Meeting, Director of Strategic Initiatives Tami Yellico reported that the COGCC Inspector who had been onsite the night before smelled the odor and that the COGCC would be issuing corrective action.  Ms. Yellico also added in response to questions from Council Member Castriotta that, “We will talk to them [Extraction] about it.”

In response to Extraction’s June 5 statement which contradicts the corrective action that Extraction took, Ms. Yellico stated in a June 7 email that she has “asked COGCC for further detail on the corrective action, and their opinion as to the correlation of the drilling mud to the odor in particular.”  Ms. Yellico also stated that Extraction’s response was public information, although it has not been published as an Oil and Gas Update.  Here is the text of Extraction’s response, followed by points that are refuted by residents:

“Per our conversations today, please reference the below clarification of questions that we have discussed regarding Gibson D822 base mud fluid. We are continuing to discuss with Gibson, and hope to be able to provide more clarifying information soon. Please forward to other city staff as necessary.”

“Question: Explanation of how neutralizing agent neutralizes odor.”

“Benzaco Odor-Armor is blended with the existing mud constituents allowing it to directly contact potentially odorous components, changing them at the molecular level. Unlike masking agents that add to the overall odor intensity by introducing an odor stronger than the offending malodor, Odor-Armor is true neutralizing technology that reduces and eliminates odors.”

“Question: Have we considered other fluid bases. Why is Gibson D822 still preferable?

“Yes. The base fluid Gibson D822 meets all requirements under Extraction’s Operator Agreement with Broomfield and has not been correlated to any instance of odor with respect to Extraction’s operations in Broomfield. Gibson D822 offers preferable health, safety and environmental properties comparative to other available OBM, including low aromatics, a high flashpoint, and low to trace BTEX constituent mole fractions.” 

“To our knowledge, the data available publicly through Broomfield’s own air monitoring program have not detected any elevated levels of pollutants at the numerous air monitoring sites surrounding the Interchange Pad.”

“Question: Why Crestone’s base is not preferable?”

“We believe that Crestone is utilizing Neoflo. The associated product safety data sheet identifies Neoflo as a Category 4 flammable liquid. Gibson D822 is not rated (i.e., flammability risk is so low that hazardous materials signage is not even required on trucks carrying Gibson D822).”  

“Additionally, in the view of Extraction, the following hazards noted on the Neoflo SDS are problematic:”

  • “Electrostatic charges may be generated during pumping. Electrostatic discharge may cause fire.”
  • “Even with proper grounding and bonding, this material can still accumulate an electrostatic charge. “
  • “Flammable vapours may be present even at temperatures below the flash point.”
  • “Flammable vapour is heavier than air, spreads along the ground and distant ignition is possible.”
  • “Will float and can be reignited on surface water.” 


Claude Boiteau

Extraction Oil & Gas”

In response to Extraction’s statement, residents living near Interchange B pointed out that Extraction’s response was not only contradictory to the actions they took but Extraction also ignored the fact that the neutralizer only impacts the odor.  It does not eliminate the underlying volatile organic compounds (VOCs) or polycyclic aromatic hydrocarbons (PAHs) which are exposing them to short-term eye and lung irritation and long-term cancer risk.  Residents are concerned that Extraction is just masking the odor while the toxic chemicals are still being dispersed through the air.

Use of this drilling mud will continue while two more previously unannounced wells are drilled by Extraction on Interchange B, bringing the total number of wells drilled to twelve in the current phase.  Spudding for nineteen wells on Livingston has started and the use of drilling mud with the 100 foot rig there might begin about mid July, based on rough estimates. 

According to the Operator Agreement, Extraction was required to drill at least eight wells on Interchange B before drilling on Livingston in what has been widely referred to by Mayor Ahrens and Council as a “test” case.  The Operator Agreement between Extraction and the City states:

“48. Odor. Odor emitting from Well Sites must be controlled. Operator to prevent odors from  oil and gas operations by proactively addressing and, to the extent possible, resolving complaints filed by impacted members of the community, in coordination with City public health staff. Operator must use a filtration system or additives to the drilling and fracturing fluids to minimize odors. Operator is prohibited from masking odors from any oil and gas facility site by using masking fragrances.”