The presentation and comments run approximately 50 minutes from 3:14 to 4:05. Lisa Bracken’s comment begins at 3:51:30.
This webpage contains links to documents related to the study:
Phase III Hydrogeologic Characterization for the Mamm Creek Field Area
While this was billed as a study, it was rolled out more like a PR campaign through articles in two local newspapers. For the most part, everything that was presented at the BOCC meeting had already appeared in the press. Except the articles reported only about methane and benzene found in the water samples. At the BOCC meeting we learned that high levels of chloride were also found.
The first article was published in The Daily Sentinel on November 9: Water study finds naturally occurring methane south of Silt [subscribers only].
So, Kirby Wynn chose a newspaper that isn’t circulated in Garfield County and its content is for paid subscribers only, to leak information and results of the study in an article that also included comments from the hydro-geologist who has been hand-picked to “peer review” the study. Commissioner Jankovsky even read from the article at the meeting.
In this Sentinel article we learned —
Who: Tetra Tech, a consulting firm (more on them later)
Where: The Wasatch formation, which is the region south of Silt from West Divide Creek west toward Rifle and Mamm Creek
What: Three sets of two monitoring wells, one at 400 feet and the other at 600 feet, were drilled in the area of the West Divide Creek seep. The article does not mention that the study also included water samples taken from a nearby residential well.
Methane was found in all of the wells in the latest study. However, it determined that the gas in the shallower wells appeared to be of a biogenic source, meaning it’s a result of microbial activity. Methane in the deeper wells appears to be thermogenic, meaning it was created through geologic processes involving heat and pressure.
Thermogenic gas is the kind being targeted by energy companies. But [Dr. Geoffrey] Thyne, who provided the county with a technical review of the latest study results, said the monitoring well test locations are believed to have little or no connection to surrounding aquifers. That means they should be isolated from possible impacts of oil and gas development.
As a result, the study provides valuable information about what natural background levels of gas in the Wasatch formation look like, including thermogenic gas.
“This is kind of what the natural background is. We do have some naturally occurring methane in the background,” Thyne said.
Thyne also previously had theorized that some biogenic gas showing up in domestic groundwater had a thermogenic origin. But given the study results, “it looks like it’s not (thermogenic). It looks like it’s naturally occurring.
“… It’s now not a surprise to me that we occasionally see some biogenic methane, and we know it’s biogenic,” he said.
Thyne still is concerned that some domestic water wells may be impacted by gas development. But he said he’ll be able to use the new information, including the chemical fingerprint of natural, background gas, to go back and re-evaluate his past analysis, and possibly remove some wells from the list about which he has concerns.
He said the latest results should provide “big relief” to people concerned about methane in water.
“Hopefully people will be able to go ‘ahh, good,’” in learning about the natural explanation for at least some of the Wasatch-level methane, he said …
… Thyne said they also help indicate the limits of the extent of that contamination by clarifying what levels of naturally occurring methane exist in the area.
“We now know that West Divide is a very well-contained, very distinct or small leak. We really know that now — that’s what we got out of this study,” he said.
He said it indicates the methane impact at the nearby property of Lisa Bracken “was relatively minor” …
… The study also found benzene, a carcinogen, in several wells. Just one sample exceeded the drinking water standard of 5 parts per billion, being measured at 5.3 ppb. The study theorized that the presence of low benzene levels in several wells suggests benzene may be present naturally in the Wasatch formation.
How thoughtful of Dr. Thyne to tell us all how to feel about this. But – “big relief”? Seriously? Why would anyone think it’s a “big relief” to know there are significant levels of methane and benzene in the groundwater whether it’s naturally occurring or caused by oil & gas development? Unless we’re planning to change then name of Silt to Farting Springs, that doesn’t even make sense.
The study concludes that the methane and benzene are naturally occurring but the study does not explain how that is possible.
Dr. Thyne’s comments about the West Divide Creek seep being a “small leak” do not coincide with his Analysis of the West Divide Creek Seep. Dr. Thyne investigated the West Divide Creek seep from 2004-2009. Back then he didn’t come to the conclusion that the methane was naturally occurring. Thyne reported: “The data support the basic observations of Ms. [Lisa] Bracken. In fact, the data indicate there has been continued seepage of methane and associated hydrocarbons with the only significant decreases in gas and associated hydrocarbon concentrations in groundwater and stream samples during peak stream flow.”
Another result of the Phase III study which was not included in any of the pre-meeting press, was the presence of high levels of chloride in all the monitoring wells.
Dr. Thyne did not participate in Phase III of the study. However he has previously participated in the Mamm Creek Study and in his Review of Phase II Hydrogeologic Study, he linked methane and chloride found in water wells to gas drilling: “Concurrent with the increasing methane concentration there has been an increase in groundwater wells with elevated chloride that can be correlated to the number of gas wells. Chloride is derived from produced water.”
After the presentation on Tuesday, the Commissioners discussed having Dr. Thyne do a “peer review” of the study, which was also the subject of an article in the Post Independent the next day (11/13): Garfield County to seek follow-up ‘peer review’ of water study
However Dr. Thyne’s present opinions appear to contradict his past conclusions. Dr. Thyne previously participated in the Mamm Creek Study. Dr. Thyne is not an independent peer reviewer.
Then there’s Tetra Tech, the company that Garfield County hired to do the Phase III study.
The day after (11/13) their Phase III presentation at the BOCC meeting, Tetra Tech announced that it had been “awarded an Engineering, Procurement, and Construction (EPC) contract with Chevron Mining, Inc.”
In a November 9 article in The Greeley Tribune, Tetra Tech construction manager Lew Ladwig extolled the virtues of the oil & gas industry.
Methane, benzene, and chloride are all by-products of oil and gas drilling operations. Tetra Tech’s clients are oil & gas companies. It doesn’t take a hydro-geologist to figure out that they’re not going to point to oil & gas development as the source of the methane, benzene, and chloride in the Wasatch formation aquifer south of Silt.
Tetra Tech is not an independent consulting firm.
The day before the BOCC meeting an article in the Post Independent highlighted the results of the study [this one is free]: Garfield County commissioners, public hear water study today. (In case you don’t feel like watching the video.)
In addition the article summarized the context of the three-phase, 9-year long study this way:
The three-phase study has been in the works since 2004 after a faulty gas well operated by Encana Oil and Gas was determined to be the source of methane gas that was bubbling up in West Divide Creek.
However, the latest study determined that there is a significant amount of naturally occurring biogenic methane contributing to the methane gas that has been showing up in domestic water wells in the larger Mamm Creek region.
That’s according to a summary report on the Phase III findings from hydrologic consultants Tetra Tech out of Louisville.
The first two phases of study was paid for in part using funds from a $371,200 Colorado Oil and Gas Conservation Commission fine levied against Encana as a result of the faulty well. Garfield County paid for the Phase III study.
At the time that the $371,200 fine was levied against Encana – 2004 – it was the state’s highest penalty in the history of ever for a single drilling incident.
As John Martin wrapped up the study presentation at Tuesday’s meeting, he pointed out individuals in the room, like Lisa Bracken and Marion Wells who lived here when the Mamm Creek study began and are still here. He remarked that this document represents “nine years worth of change.”
So check out this blast from the past: EnCana fine ‘sizable’
Ironically it’s written by Dennis Webb, the same reporter who wrote the Sentinel article quoted in the beginning of this post. You MUST read the article.
The August 2004 COGCC hearing was held at the Ramada Inn in Glenwood Springs. Garfield County Attorney Don DeFord and Western Colorado Congress Attorney Carol Lamb shared the same concerns about the continued benzene contamination showing up in the monitoring wells. It’s amazing. Like a journey to Oz.
And Garfield County Commissioner John Martin was there, too. A champion of the people, he was “disappointed that EnCana, while admitting to violations, is not admitting any liability related to the gas seep.”
“If they take the responsibility, how is it that they don’t have the liability?” [John Martin] asked. He speculated that the company fears leaving itself legally exposed in the case of any lawsuits filed in connection with the suit if it admits liability.
Boy howdy — that there is “nine years worth of change” all right.