Editor's Letter: California in Hot Water over Disposal of Drilling Wastewater

A recent Environmental Protection Agency audit of the practices and regulations of California Department of Conservation's Division of Oil, Gas, and Geothermal Resources revealed that its wastewater injection wells had been permitted for disposal into high-quality aquifers, ones that were considered usable for drinking or irrigation. As such, the Department has outlined a plan to ensure that the state achieves full compliance.


Angela Godwin, Chief Editor

Oil and gas production in California is big business, yielding $34 billion a year and employing more than 25,000 people. In fact, producing around 575,000 barrels a day, it's the third largest oil-producing state in the U.S. That's a lot of oil...and a lot of wastewater.

California estimates that over 50,000 oilfield injection wells are in operation in the state. A subset of those -- classified as Class II injection wells -- are for the disposal of fluids associated with oil and natural gas production operations (typically brine produced during the extraction process). In 1983, the U.S. Environmental Protection Agency granted "primacy" to the California Department of Conservation's Division of Oil, Gas, and Geothermal Resources (DOGGR or Division) for Class II injection wells, meaning that the Division is responsible for administering the Underground Injection and Control (UIC) program for Class II wells under the federal Safe Drinking Water Act. This includes the permitting, inspection, enforcement, mechanical integrity testing, plugging and abandonment oversight, data management, and public outreach related to Class II wells.

Fast forward a few decades... In 2010, prompted by concern about DOGGR's oversight of the UIC program, EPA launched an audit of the Division's practices and regulations. The subsequent 2011 report by the Horsley Witten Group revealed a number of serious deficiencies, which the EPA asked DOGGR to resolve. Further review the following year of DOGGR's aquifer exemptions exposed some startling information: wastewater injection wells had been permitted for disposal into high-quality aquifers, ones that were considered usable for drinking or irrigation.

In general, an aquifer is considered usable if total dissolved solids are below 3,000 ppm. To dispose of wastewater into one of these protected aquifers requires an exemption from EPA. But the agency found that DOGGR allowed well permits in eleven non-exempt aquifers. At least, EPA considered them non-exempt.

As it turns out, there were two versions of DOGGR's primacy agreement: one that listed the eleven aquifers in question among those suitable for wastewater injection with a permit; and one that did not. The latter version is what was on file with EPA.

It's not clear (to anyone) how the mix-up happened, but the result is crystal: eleven sources of water -- an especially critical resource given California's prolonged drought -- were exposed to potential contamination.

The word "potential" is very important here: at this juncture, there has been no evidence to suggest contamination of drinking water wells near the eleven disputed aquifers.

Nonetheless, EPA directed state regulators to come up with a strategy to address the growing list of deficiencies with its UIC program and on February 6, the Department of Conservation, in conjunction with the State Water Resources Control Board, outlined a broad plan that, they say, will "ensure California achieves full compliance with the federal Safe Drinking Water Act."

Among the specific milestones outlined in the plan, the Division intends to close any wells injecting into very high-quality aquifers by Oct. 15, 2015. Further, by Feb. 17, 2017, wells injecting into lower quality (but still usable) aquifers, will be shut down unless granted an exemption by EPA. The Division will also update its data management systems, with the ultimate goal of having a fully searchable database of all injection wells.

Pending approval of the plan by EPA, DOGGR expects to begin rulemaking in April.

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