In the Pits

November 16, 2014
Oil waste water pit
Andrew Grinberg
Oil and Gas Wastewater Disposal into Open Unlined Pits and the Threat to California’s Water and Air

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As the fourth largest oil producing state in the country, California must responsibly manage the massive waste stream generated by the oil and gas sector. This report examines the risks to California water and air quality associated with just one part of this waste stream: oil and gas wastewater disposal into open-air and unlined pits. The investigation that preceded this report found a long-term ongoing failure on the part of regulatory entities tasked with protecting public health and the environment to properly monitor and restrict the use of these pits, despite demonstrated threats to public health and the environment.

Pipes dumping into an unlined pitIn 2013, industry produced 8 billion gallons of oil in California, and 130 billion gallons of wastewater, or approximately 15 barrels of wastewater for every barrel of oil that is produced. Oil and gas wastewater contains both naturally occurring and added contaminants, including carcinogens, heavy metals, radioactive materials and salts. In California, oil and gas wastewater is disposed of in four different ways: underground injection into class II disposal wells; reinjection for enhanced oil recovery (EOR); irrigation of crops; or disposal into unlined pits, also known as sumps. Each presents its own unique challenges and threats to water quality, health and the environment, but unlined and open-air pits are especially troubling because they are designed to percolate and evaporate toxic chemicals into the environment.

Unlined pits are a commonly used disposal method for an unknown, yet potentially significant, portion of the 130 billion gallons of wastewater produced annually from oil and gas operations. According to Division of Oil, Gas and Geothermal Resources (DOGGR) records, at least 432 unlined pits are currently being used for disposal of oil and gas wastewater in the Central Valley, and most have been operating with significantly out-of-date waste discharge permits, or no permits at all. The discharge of wastewater into unlined pits threatens water resources, including potential sources of drinking and irrigation water, and impacts air quality due to the off-gassing of chemicals from the wastewater. The majority of these pits are near waterways, increasing the likelihood that spills and surface-to-groundwater migration will impact water resources. There has been no comprehensive review of locations of pits in relation to high quality groundwater.

Wastewater in an unlined pitAfter learning about an unlined pit site, Clean Water Action began to investigate one pair of pits located near McKittrick in Kern County. By reviewing public documents, and using citizen collected air quality samples, the investigation found documentation of a plume of wastewater containing heavy metals such as boron, high salinity, and other constituents of concern, that has migrated towards high quality, useable groundwater resources. The Central Valley Regional Water Quality Control Board (CVRWQCB or Central Valley Board) has required groundwater testing near the site since 2004. The test results — all public documents — indicate that a plume of wastewater, matching the characteristics of the wastewater in the pits, extends close to a mile to the northeast of the pits. It extends towards the Kern River Flood Channel, the California Aqueduct and high quality groundwater used for significant agricultural activity. The public documents also indicate a complete lack of enforcement of regulations by the Central Valley Board, which has allowed discharge into these pits since the 1950s, despite its own records indicating industry non-compliance with state and regional water quality laws.

Air quality sampling (analyzed by an independent lab) at the pits identified health-threatening and climate-changing pollution. Samples showed the presence of 24 volatile organic compounds (VOC’s), and methane, as well as Benzene and 2-Hexanone, above the Long Term Effects Screening Levels.* After receiving a complaint of noxious odors at the pits, the San Joaquin Valley Air Pollution Control District (the District) responded with a claim of “no threat,” based on self-reported sampling by the operator of the pits. The District did not conduct independent air or water sampling.

This report focuses on addressing the threats of unlined pits for wastewater disposal and recommends the following policies:

  • DOGGR and the State Water Board should immediately prohibit discharge of oil and gas waste to unlined pits.

These agencies should also investigate and ensure remediation of impacts associated with past discharges into these pits by:

  • Developing an inventory of historic wastewater disposal locations into unlined pits;
  • Investigating whether groundwater quality has been degraded by currently operating and historic unlined pits;
  • Identifying responsible parties and requiring remediation of groundwater degradation that has occurred due to disposal into unlined pits; and
  • Developing a plan for remediation of groundwater for which no responsible party can be identified.

The California Air Resources Board and the San Joaquin Valley Air Pollution Control District should increase oversight of open pits by:

  • Enforcing existing laws such as District Rule 4402, by conducting independent sampling of water and air quality instead of data that is self-reported by operators;
  • Conducting inventories of emissions from open pits; and
  • Exploring whether a statewide rule is needed for limiting emissions from pits.

On September 5, 2014, Clean Water Action made a formal request to the Central Valley Water Board to prohibit the discharge of oil and gas wastewater to unlined pits. The Central Valley Board responded on September 29 by denying the request and stating that staff would continue to investigate pits on a case-by-case basis. This response does not address the numerous concerns outlined in the request for closure and this report, and represents a failure to provide adequate protections for Central Valley groundwater.

This report contributes to a mounting body of evidence of California’s failure to regulate adequately the oil and gas industry. This evidence calls into question the state’s ability to withstand industry influence and meet its statutory mandate to protect public health, private property, and public trust resources.

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