Hydraulic Fracturing for Oil and Gas Production in California — Water Use and Water Quality

Nichols, Eric

Hydraulic Fracturing for Oil and Gas Production in California — Water Use and Water Quality

Thursday, November 13, 2014: 5:30 p.m.

Thomas Johnson, PG(CA), CHG(CA) , Thomas Johnson Associates, Sausalito, CA

Eric Nichols, PE(CA) , Consultant, Newfields, NH

Hydraulic fracturing has been used in California for well stimulation since 1953. In 2013, 830 wells were hydraulically fractured. Most wells are 1000 to 4000 feet deep. The average volume of water used to hydraulically fracture each well in 2013 was 127,000 gallons (0.39 AF), and the total volume of water used in 2013 for hydraulic fracturing was 323 AF.

The oil industry is exploring the potential of the deep Monterey shale at depths of 7000 to 14,000 feet. Initial exploratory wells have used an average 10 AF of water for hydraulically fracturing each well. Based on recent estimates of Monterey oil production, the volume of water expected to be used by 2030 for all hydraulic fracturing in California, including the Monterey Formation, is less than 2500 AF, representing 0.004% of freshwater usage in California.

There have been no documented incidents of groundwater contamination in California caused by hydraulic fracturing because: (1) California has strict regulations for well construction to protect groundwater; (2) hydraulic fracturing fluid consists primarily of non-toxic materials (water, sand, guar, etc.); (3) oil producing zones are isolated from freshwater and separated from overlying aquifers by several thousand feet of sediment; and (4) the practice has primarily been used in the western San Joaquin Valley, where freshwater is absent and groundwater is often naturally saline.

The deep Monterey Formation in the San Joaquin Valley is separated from overlying aquifers by 5000 to 13,000 feet of sediment, and groundwater below a depth of 1000 feet in many areas has been found to be brackish or saline, and commonly contains natural gas.

Current regulations require groundwater monitoring or proof that no protected groundwater is present. Protected groundwater contains less than 10,000 mg/L TDS and is not in an oil- or gas-producing zone. Regulations also require public disclosure of all hydraulic fracturing fluid components, baseline groundwater sampling, and ongoing monitoring.

Thomas Johnson, PG(CA), CHG(CA), Thomas Johnson Associates, Sausalito, CA

Thomas Johnson is Principal Hydrogeologist of Thomas Johnson Associates, a water and environmental expert consulting firm. He has 38 years of experience in groundwater and environmental consulting and research, and has testified as an expert in state and federal courts regarding groundwater and environmental matters for more than 30 years. Johnson formerly was President of the California Groundwater Resources Association, and Chair of the Board of Directors for the National Ground Water Association, Association of Ground Water Scientists and Engineers.

Eric Nichols, PE(CA), Consultant, Newfields, NH

Eric M. Nichols, PE, is an independent consultant and groundwater hydrologist with 27 years of experience interpreting subsurface conditions for groundwater supply, remedial design, upstream water strategy, risk assessment, regulatory compliance, and litigation support. Nichols provides senior technical direction for subsurface remediation and water resource projects. Nichols is an active educator and has served on several panels and committees related to vapor intrusion, fuel oxygenates, LNAPL management, state cleanup policies, risk-based corrective action, and natural attenuation.