LBNL-ESD Key Player in Hydraulic Fracturing Study
Source: Jens Birkholzer and Dan Hawkes
On August 28 (2014), the California Council on Science and Technology (CCST) released an independent report reviewing well-stimulation technologies, including hydraulic fracturing, used in on-shore oil reservoirs in the state of California. This study, commissioned by the Federal Bureau of Land Management (BLM), will be used to inform BLM’s oil and gas policies in California.
As stated in the CCST press release, the report describes “current well stimulation activities in California—how, when, and where they are currently applied, where they might be applied in the future, and how this practice differs from other states. The report assesses information relevant to the potential future use of these technologies, and how they might or might not directly impact water supply, water quality, air quality, greenhouse gas emissions, seismicity, ecology, traffic and noise.”
The released statement goes on to describe the key role that LBNL played in the creation of the report. “Lawrence Berkeley National Laboratory (Berkeley Lab), with help from the Pacific Institute, developed the report findings under the guidance of a steering committee of experts chartered by CCST.” The steering committee, chaired by Dr. Jane C. S. Long, consisted of 12 subject-matter experts drawn from many of the major research institutes in the state, as well as experts from other states with experience in well stimulation technology. “The people of California should know that the scientists conducting this study brought a wide variety of expertise, extensive experience and open minds to this assessment,” Long said. “We conducted a careful and fact-based review that achieved consensus on all conclusions.”
ESD Deputy Director Jens Birkholzer, Project Leader for Berkeley Lab, added, “Participating scientists at the lab have been working to understand and ameliorate the impacts of hydraulic fracturing for some time and the lab was pleased this expertise could be of service to BLM and the state.”
The report arrives at a number of important conclusions, including:
- Well stimulation in California is different than in other states. Available data suggest that present-day well stimulation practices in California are different from other states such as Texas and North Dakota, primarily due to differences in the geology of the petroleum reservoirs.
- The most likely scenario for future oil recovery using hydraulic fracturing is expanded production in and near existing oil fields in the San Joaquin Basin in a manner quite similar to the production practices of today. Some of this production will require well stimulation. Current production in the Los Angeles Basin does not depend heavily on well stimulation, and similar future production could likely occur without these technologies.
- It is highly uncertain whether oil reserves exist in the deep source rocks of the Monterey Formation, which would most certainly require well stimulation to enable production. Berkeley Lab investigators found no reports of successful production from these deep source rocks.
- Current hydraulic fracturing operations in California require a small fraction of statewide water use. In California a hydraulic fracturing operation can consume between 130,000 to 210,000 gallons of water per well on average, compared to about 4 million gallons per well used on average in the Eagle Ford Formation in Texas.
- California needs to develop an accurate understanding about the location, depth, and quality of groundwater in oil- and gas-producing regions in order to evaluate the risk of well stimulation to groundwater. There are no publicly reported instances of potable water contamination from subsurface releases in California. However, more than half of the stimulated oil wells in California have shallow depth (less than 2,000 feet). Shallow hydraulic fracturing poses a potential risk for groundwater if usable aquifers are nearby.
- Well stimulation technologies, as currently practiced in California, do not result in a significant increase in seismic hazard. The pressure increases from hydraulic fracturing are too small and too short in duration to be able to produce a felt, let alone damaging, earthquake. In California, only one minor, anomalous earthquake (which occurred in 1991) has been linked to hydraulic fracturing to date.
- Overall, in California, for industry practice of today, the direct environmental impacts of well stimulation practice appear to be relatively limited. If these well stimulation technologies enable a significant increase in production in the future, the primary impacts on California’s environment will likely be caused by the increase in production activities in general.
Over the next year, CCST will lead an expert team, including Lawrence Berkeley National Laboratory and the Pacific Institute, to produce the scientific assessment of well stimulation technology required by Senate Bill 4, which mandates stronger state oversight of well stimulation within California. This report will incorporate and expand the analysis done for BLM and will include more recent disclosure data and a review of offshore and gas well stimulation not covered in the BLM report.
In addition to Birkholzer, a number of ESD scientists made significant contributions to the report, including Preston Jordan, Jim Houseworth, Pat Dobson, Matt Reagan, Will Stringfellow, Ruth Tinnacher, Charuleka Varadharajan, Bill Foxall, and Nate Lindsey. Dev Millstein and Marc Fischer of EETD were also key members of the team. The full report and executive summary can be viewed at http://ccst.us/BLMreport.