HOBACK BASIN – State records for the unpermitted 1980s’ Chevron “sludge pit” in Bondurant, on a 10.1-acre site selected by Jackson Fork Ranch owner Joe Ricketts for his resort’s underground 100-car parking garage, show longtime concerns about potential groundwater and soil contamination.

In the meantime, Sublette County officials are holding off on hearing Ricketts’ conditional use permit (CUP) application for the subterranean garage on the site of the Chevron Pit, which was scheduled for their vote on Feb. 2.

The CUP application process before the Board of Sublette County Commissioners’ Feb. 2 meeting stalled, after Rio Verde Engineering’s Mike Jackson cited scheduling conflicts, restarting the process at their first April 2 meeting.

The month of April figured into other citizens’ comments at the Feb. 2 meeting, asking why Ricketts is allowed to build a resort duplex cabin during Wyoming Game and Fish’s recommended critical wildlife winter-range closures.

In the commissioners’ Dec. 21, 2021, resolution to approve Ricketts’ requested rezoning of 56 Agriculture acres to Recreational Services, chair Sam White added a stipulation.

“Construction – No construction between Nov. 15 and April 30 as recommended by Game and Fish in their letter dated Nov. 19, 2021.”

Heavy equipment

Former Sublette County Planning & Zoning Board member Pat Burroughs, who lives on Upper Hoback Road adjacent to Jackson Fork Ranch and across the county road from the planned resort, said last week she called county planner Dennis Fornstrom to ask about heavy construction equipment moving around the resort portion.

Fornstrom told Burroughs staging equipment was not “construction.” He approved the building permit in June 2023; he declined to forward any supplemental building permit materials, citing a new public records request process. Scant planning and zoning data are posted on the Sublette County GIS map, only Ricketts’ building permit.

Anyone asking for a county document must fill out a records request to County Clerk Carrie Long’s office, Fornstrom said.

Dan Bailey, also a neighbor, asked White on Feb. 2 if commissioners would determine if the equipment use violated the intent of his 2021 stipulation. White said he would look into it and that the county was already aware of the topic.

With no one from Ricketts’ camp on any county agenda until April, the potential for Ricketts’ resort and road construction – “ground-disturbing activities – might continue unchecked by county officials in the meantime. At that point, only three weeks remain in the stipulated construction closure to protect moose and elk in critical winter ranges and mule deer and other wildlife migrations through the Hoback Basin.

Asked if he was updated on visible, ongoing heavy-equipments’ travel and uses possibly violating that 2021 stipulation, Sublette County Attorney Clayton Melinkovich said, “I cannot comment on client communications.”

Chevron Pit

As reported last week, Wyoming DEQ had issued a notice of violation (NOV) in 1983 to Chevron for not properly permitting its set of three unlined drilling-waste pits on the McNeel Ranch eventually purchased by Ricketts.

Rather than pursue DEQ’s process for a permit, Chevron chose to abandon the McNeel Pit and hauled off dump-truck loads of contaminated sludge – drilling fluids, saline water and solids. The company was allowed to let the last 10 percent of the “mud” evaporate in place. The 800-by-200-by-7-foot pit, cut into the “terrace remnant” 1/4 mile above the Hoback River, was backfilled and reseeded in 1983.

Next, Chevron installed one monitoring well above and three below the drilling-waste pit, and some DEQ and Chevron- contracted water-quality tests were conducted over the next several years. The pit had been enclosed by a berm dug from the ground that was rolled back into the pit.

Some people revisiting the former pit said it was difficult to tell where it had been, if they hadn’t seen it for themselves.

The Chevron Pit and its potential contamination of the ground and groundwater faded from other people’s minds.

Catching up

DEQ’s Thomas Williams performed the last water tests in 1987, according to the 1997 request by Chevron for a groundwater pollution control system. It quoted Williams’ findings.

“1. Seepage from former oil field waste disposal pits have had an impact on the inorganic quality of the unconfined shallow groundwater aquifer. The dissolved solids concentration in the down-gradient wells are elevated by several hundreds of milligrams per liter total dissolved solids in comparison to the up-gradient well. The concentrations of other cations and anions such as sulfate, chloride and sodium are also above background levels;

“2. No organic contamination, as is evidenced by non-detectable concentrations of benzene, toluene and xylene, has been documented from the sampling analytical results;

“3. The concentrations of inorganic contaminates do not appear to be decreasing over time.”

Land for sale

In 1995, the McNeels had a buyer who wanted a clean slate from the Chevron Pit; the water was still advised for only livestock and agriculture use, not domestic.

Later emails showed the Chevron Pit “had fallen through the cracks.”

In July 1997, Chevron’s Betsy Wagner asked DEQ if the McNeel Pit was “closed.”

The DEQ advised, “As we discussed last week, the McNeel pit site has not been closed. I discussed the issue of closure with Dave Matthews on 11/13/95. At that time, the most current sampling event was in 1987. I told Dave that it may be possible to obtain a ‘No Further Action’ status using the historical data. This status, however, is not the same as ‘Closure;’ it would require a public hearing, and bankers and realtors don't always accept this status. … (I)t would be preferred to obtain current data by resampling the monitor wells. If it can be demonstrated that the groundwater has cleaned up within the class of use, it is probable that ‘Closure’ can be granted. To date, I have not received a response from Chevron.”

Ten years after

Chevron’s lab tested three down-gradient monitoring well samples in 1997.

“TPH and BETX continue to fall below cleanup standards. Background groundwater is assumed to be Class I. TDS, sulfate, chromium and iron exceed Class I. All other constituents analyzed are within class,” the lab reported.

The uphill test hole was long destroyed by snow-removal equipment, Wagner reported.

The DEQ permit sought for additional cleanup required the operator’s strict and accurate monitoring. DEQ would require a “recommended corrective action plan” for “additional subsurface investigation work” to define subsurface and contaminate conditions in both soil and groundwater.

“Corrective measures” included removing any contamination, controlling its migration, storing or containing the dissolved groundwater and restoring groundwater quality to “within Wyoming groundwater quality standards.”

Then Chevron could request the site’s closure or “no further action.”

Then-DEQ Director Dennis Hemmer concluded in the agency’s authorization: “The issuance of this permit does not relieve the permittee from obligations to complete the extent of contamination study and any further remedial work which may be required. Depending on the results of the subsurface investigation, additional site investigations or remedial actions may be required by the WQD.”

In January 1998, Wagner reported Delta Environmental Consultants installed one well uphill from the former pit and three soil borings drilled in the centers of the three smaller pits. Nineteen more soil probes were inserted “east of the pit bluff” and across the center pit. A total of 16 water samples were collected from the soil probes and monitoring well. Fourteen water samples were analyzed for dissolved chromium, dissolved iron, total dissolved solids and sulfate.

One water sample collected from the middle pit area was analyzed for total recoverable petroleum hydrocarbons (TRPH), and one sample from the middle pit area was analyzed for benzene, toluene, ethylbenzene, xylenes (BTEX) and total petroleum hydrocarbons (TPH). Four soil samples were collected from soil borings SB-1, SB-2 and SB-3. Each soil sample was analyzed for TRPH.

Groundwater and soil samples were submitted to American Environmental Network (AEN) of Pleasant Hill, California.

Those and many earlier soil-boring logs and water-quality sample results are included with DEQ records, and were not reviewed. Charts showed higher total dissolved solids, chloride and sulfate while chromium were not detected in every sample at that time except to the northeast and southeast in 1997.

Solidification

In May 1998, Wagner asked if the DEQ or the Wyoming Oil and Gas Commission (WOGC) would take over remediation. DEQ deputy director Robert Bennett wrote to WOGC supervisor Don Likwartz, “It is my understanding that the pits are located on private lands (McNeel property) and were permitted as sludge pits during the drilling of the well. The pits were covered but some or all of the sludge was not removed. We are in full agreement and support of the Commission's pursuit in this matter.”

However, the sludge pit was leased on a private ranch and trucked from Forest Service well pads permitted by the Bureau of Land Management.

Conversations crisscrossed over exactly who was responsible for working further with Chevron.

A DEQ geologist reviewed Jan. 2, 1998, tests in July 1998.

“I. Groundwater sampling results indicate elevated levels of total dissolved solids, chromium, chloride, and sulfate, and occasionally iron in groundwater samples down-gradient of the former pits, and in samples collected in the area of the former pits. However, none of the groundwater samples down-gradient of the former pits contained concentrations of analytes above Wyoming Class I standards for groundwater. Please clarify whether samples identified on Table 1 as MID PIT (Center), PNE-1, and PSE-1 were taken from groundwater or from free liquid in sludge remaining in the former pit area.”

The DEQ replied to Wagner: “As we have discussed on the phone, one round of groundwater samples was to be collected on or about July 23, 1998. Per a subsequent conversation between Mark Thiesse of WDEQ and yourself, an additional round of groundwater samples will be collected in early 1999 after stabilization of remaining sludge has been completed. If the results from groundwater samples collected in early 1999 show no analytes above Class I standards, no additional groundwater sampling will be necessary.”

WOGC stepped up in 1998 to oversee “certain chemical and mechanical treatments” of “reserve pits” as long as they did not disturb a pit’s secured lining – which the McNeel Pit never had.

Wagner informed WOGC that previous “contributors” to the pit, opened in 1997, were Rainbow Resources (Chevron), Chevron and Superior Oil (Rainbow Resources) including five exploratory wells, four in Teton County. “The type of drilling mud placed in the pits contained lignite-sulfonate and chromium but had little hydrocarbon. There is no record in our files as to the total volume of fluids sent to the pits.”

Chevron did find contaminated sludge in the middle pit; it was also found in the south pit, according to Wagner. Chevron’s proposal was to solidify the sludge onsite.

Wagner offered this plan to WOGC – to scrape and store topsoil separately from the underlying soil, dig down to the remaining sludge areas and move it all to the larger pocket in the middle pit. Then the sludge would be “solidified,” the underlying soil replaced and the sludge covered with at least 3.5 feet of soil. The site would be reseeded that fall, she wrote.

WOGC reported the sludge to be 10 inches thick, “black in color and plastic in texture.”

On Oct. 1, 1998, a WOGC geologist stated in a memo, “… I would not recommend that any structure intended for human habitation be build (sic) over the former pit cell because of foundation engineering concerns,” noting a “very negligible” soil foundation.

A week later, Wagner wrote the DEQ that Chevron and WOGC were confident the solidification remedied the remaining sludge, still with concerns about continuing high total dissolved solids and chlorides. “A final report will be sent (and a) closure notice will be sent to you after (further) testing is completed.”

Handwritten, faxed and emailed notes in the DEQ's records imply but do not confirm that DEQ released Chevron from further mediation of the Chevron Pit.

The McNeel Ranch was sold in 1999 with the exception of the Chevron Pit; Joe Ricketts is the current owner of that parcel now with the rest of the former McNeel Ranch.