A new report by an East Coast environmental study group concludes that the California agency responsible for monitoring oil production has routinely overlooked serious wastewater injection issues in the oil fields of Monterey and Fresno counties.
The Environmental Action Center, based in Washington, D.C., says its yearlong study found that the state Department of Conservation, Division of Oil, Gas, and Geothermal Resources (DOGGR), has ignored the industry practice of injecting too much wastewater under too much pressure into underground rock formations, which can cause contaminated wastewater to migrate toward underground sources of drinking water. See the study here.
While it cites no examples of contaminated drinking or irrigation water, the center has petitioned the DOGGR to better enforce existing regulations and to reject pending requests for exemptions that would allow dangerous practices to continue, particularly in the Lombardi and Aurignac sands in Monterey County.
The study was performed by David Reed and Hannah Fish of the EAC, a non-profit group that focuses on water pollution issues nationally. Based on the cited source materials, it appears that much of their work consisted of a review of state and federal regulatory records pertaining to the Central California oil fields. Monterey County’s production is centered in San Ardo while Fresno County’s industry is mostly in the Coalinga area.
It was not immediately clear whether the report’s release last week was timed to influence the fate of Measure Z, the Nov. 8 ballot measure that would ban fracking in Monterey County and force the oil industry to adopt more sophisticated methods of treating the wastewater that results from their steam-injection process.
The wastewater issue has become a focus of the Measure Z campaign. While the initial thrust of the ballot measure is to ban fracking in Monterey County, the oil industry’s opposition campaign correctly argues that there has been no fracking here but that the measure would impose costly new regulations on an industry that is already heavily regulated. The EAC study questions the adequacy of the existing regulations.
The report’s executive summary says, “When operators inject too much wastewater, at pressures that exceed the pressures in the injection zone, vertical fractures can form in the rock formations, which results in contaminated oil and gas wastewater migrating out of the injection zone. If allowed to migrate far enough upwards, the wastewater could potentially reach more shallow underground sources of drinking water.
“In injection zones such as the Lombardi and Aurignac sands in Monterey County, which are now being considered for an aquifer exemption, overpressure problems have existed since the beginning of oil and gas wastewater disposal in the area – at least since the 1980’s.”
The report says the state agency has routinely overlooked wastewater issues in violation of state and federal rules.
“There are many significant environmental impacts resulting from oil and gas exploration and production, however, one of the most significant is the disposal of wastewater produced during oil and gas operations. Oil and gas operations use millions of gallons of water each year, and industry operators are faced with decisions regarding how to dispose of that wastewater.
“One of the most economical methods of oil and gas wastewater disposal – injecting the wastewater back into underground injection wells – is also one of the most problematic. In theory, oil and gas operators inject the wastewater into underground rock formations, known by their characteristics as suitable ‘geologic zones.’ Different geologic zones are suited for wastewater disposal based on their depth, permeability, and confinement characteristics. Additionally, geologic zones used for wastewater disposal in theory are not considered as being potential sources of drinking water, because of chemical characteristics of the water already present in the formation.”
The Monterey County oil producers say their wastewater is injected to underground basins that are harmlessly separated from potable water by impermeable rock layers.
The report continues, “An aquifer, or an underground source of drinking water, needs to be exempted by the United States Environmental Protection Agency or equivalent state agency to be used as a geologic zone for underground wastewater disposal. Generally, deep underground aquifers are not suitable for drinking water, while more shallow aquifers are.” The Monterey County and Fresno County operations have not been granted the proper exemptions and, therefore, are operating illegally, the report contends.
“DOGGR must enforce existing legal requirements that apply to well operators. DOGGR must also use reasoned discretion and shut down injection projects where appropriate.”
The report says the DOGGR is currently in the process of reviewing and updating its guidelines for disposal wells pursuant to state legislation and a federally mandated overhaul of its permitting program.
“Historically, DOGGR failed to require oil and gas operators to perform the legally required geologic, hydrologic and engineering studies prior to approving wastewater disposal,” the report says, noting that the process of reviewing approximately 255 drilling sites in its coastal district would be a dauntingly time-consuming task.
One of the issues oil producers must address is the amount of pressure used to pump wastewater back into the ground. Many of the Central California wells, particularly in Monterey County’s San Ardo field, have been flagged by the state agency for “unacceptably high hydrostatic pressure.”