Injection of Petroleum Waste Program

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Program Information

Injection of Class II waste fluid in connection with conventional oil or natural gas production can result in harm to the environment and contaminate valuable ground water resources. Permits are required, construction plans approved, a monitoring program implemented, and operating standards met. Environmental Health inspects wells and samples fluids that are injected into the wells.

What Are These Wells Used For & Why Are They Regulated? 

When natural gas is pumped from deep below the ground, surface water and natural chemical contaminates are pumped to the surface with it. These are separated before the natural gas is placed into pipelines for transport. Wells formerly used to pump natural gas are often used to re-inject the water and the contaminates back into these deep wells. If these injection wells develop a leak, then drinking water supplies or water used by agriculture could be contaminated. 

How Does This Program Protect The Groundwater? 

The location of the injection wells and depth of injection is strictly controlled. Each well must meet construction standards and must be periodically observed and tested to ensure they cannot leak contaminated water into usable groundwater zones. To prevent the use of these wells for disposal of other toxic wastes, the injected substances are sampled on a regular basis. Environmental Health conducts routine inspections and sampling, and requires submittal of test results conducted by the owners/operators of injection wells. 

Contact Us

 Hazardous Materials Unit
137 N. Cottonwood St. Suite 2400
Woodland, CA 95695

Phone: (530) 666-8646
Fax: (530) 669-1448
Email: Environmental.Health@yolocounty.org