Task Force Report: Key Impact Areas of Shale Development in Texas

The environmental and socioeconomic impacts of shale oil and gas development in Texas have been assessed(Source: TAMEST) by The Academy of Medicine, Engineering & Science of Texas (TAMEST) Shale Task Force. Seismicity, land, air, water, transportation, and economic and social impacts were considered.

Seismicity

The majority of known faults in the subsurface in Texas is stable and are not prone to generating earthquakes. However, there has been an increase in the rate of recorded seismicity in the state over the last several years. Between 1975 and 2008 there was, on average, one to two earthquakes per year with a magnitude greater than M3.0. Between 2008 and 2016, the rate increased to an average of about 12 to 15 earthquakes per year.

To date, potentially induced earthquakes in Texas, felt at the surface, have been associated with fluid disposal in Class II disposal wells, not with the hydraulic fracturing process.

Recommendations

• Future geologic and seismological research initiatives should develop improved and transparent approaches that seek to balance concerns surrounding data handling and sharing, and that promote sharing of data.

• Development of a common data platform and standardized data formats could enable various entities collecting data to contribute to better data integration. It also could facilitate interdisciplinary collaboration directed toward mitigation and avoidance of induced seismicity.

Land Resources

Shale development in Texas takes place largely on private lands, which generally are not sites of formal environmental impact studies. The few studies that have been conducted on erosion and soil contamination from oil and gas development in Texas indicate that well pad development has an increased potential for erosion, and that soil contamination is possible from oil and gas production.

The vast number of new wells drilled in shale formations in Texas since 2007 have had substantial spatial impacts on the landscape. However, horizontal wells have a smaller impact than the equivalent number of vertical wells would have had. When operators use a single well pad for multiple wells, surface impacts are significantly reduced.

Recommendations

• Baseline land and habitat conditions at the oil and gas play level should be characterized, and changes to wildlife populations and vegetation should be tracked over time where there are opportunities on both private and public lands.

• The effectiveness of voluntary programs to conserve at-risk species should be studied, along with options for incentives to conserve at-risk species and reduce effects on land resources by oil and gas development activities.

Air Quality

Emissions from oil and gas operations in Texas roughly scale with oil and gas production rates.

The production of shale resources results in emissions of greenhouse gases, photochemical air pollutants, and toxic air pollutants. Shale resource development both directly and indirectly impacts air quality. Indirect impacts include reductions in emissions associated with the substitution of natural gas for coal in electricity generation.

Recommendation

• There is limited information concerning exposures to air toxics emissions and their corresponding health impacts. Targeted research in this area should be conducted.

Water Quantity and Quality

Some of the most significant public concerns surrounding the application of hydraulic fracturing operations regard possible effects on both the available supply of water and possible effects on water quality. Millions of gallons of water are used to fracture a single well. Nevertheless, overall water use by hydraulic fracturing is small compared to that used by agriculture or municipalities. Water used in hydraulic fracturing processes in Texas represents a small fraction—less than 1 percent—of total water use state-wide.

The amount of water used for hydraulic fracturing can be important, however, in areas where water use is otherwise low, such as rural energy-producing counties. The impact of water use on supply can be reduced by limiting freshwater use and using brackish groundwater or produced water for hydraulic fracturing.

Hydraulic fracturing is also a potential concern to drinking water supplies. There is little chance of migration of hydrocarbons or brines from producing formations to drinking water aquifers, but near surface and surface spills or leaks may pose the dominant risk of hydraulic fracturing operations to water resources. The depth separation between oil-bearing zones and drinking water-bearing zones in Texas makes direct fracturing into drinking water zones unlikely, and it has not been observed in the state.

Increased complexity of surface fluid management -- for example by treatment and use/reuse operations -- may increase the potential for spills or leaks and therefore the risk to land and water resources.

Recommendations

Water Availability and Supply

• Research and testing to enable the use of brackish groundwater and produced waters for hydraulic fracturing should be encouraged.

• Aquifer investigations including pumping tests and chemical analyses should be used to better characterize the productivity and chemical composition of brackish groundwater, and variability of these properties, in oil and gas producing areas.

Subsurface Contamination by Fracturing or Formation Fluid

• The collection and sharing of pressure data relevant to communication between water-bearing and producing strata — including non-commercial flow zones or across wells -- could help identify and avoid potential concerns.

Spills of Flowback Water, Drilling Fluid, and Formation Water at the Surface

• Statewide leak and spill reporting requirements for produced water should be considered. For all spilled substances, reporting requirements should be improved to aid identification of the primary sources of leaks and appropriate management responses.

• Texas regulators and industry should continue to develop and apply best management practices relative to well casing design and construction, and surface management of oil and gas operations, to reduce inadvertent release of fluids.

Wastewater Treatment and/or Disposal

• Research on techniques for treating produced water cost-effectively -- particularly for uses that have minimal quality requirements, such as for hydraulic fracturing -- should be continued.

Transportation

Development of the abundant shale resources across Texas through hydraulic fracturing and multi-stage, horizontal drilling has involved increases in the volumes of equipment and personnel at well sites across the state. Not only have there been considerable increases in truck traffic across the state, other modes of transportation have also experienced a surge in traffic, as evidenced by the significant increase in energy-related activities at transportation facilities such as ports, railroads and pipelines.

These increased traffic volumes have accelerated the degradation of pavements and roadside infrastructure. The accelerated damage of pavement structures along secondary state highways and local roads has been estimated at $1.5 to $2 billion per year. Costs to the trucking industry are also significant. A preliminary evaluation of the cost in the form of additional vehicle damage and lower operating speeds estimated the cost at $1.5 to $3.5 billion per year.

There also have been increases in accidents associated with the increased traffic volumes. Traffic increases —especially truck traffic, associated with the development and production of oil and gas from shale formations in Texas -- have resulted in increases in the frequency and severity of traffic crash incidents.

Recommendations

• Enhanced efforts and support of the following research programs and strategies will improve preparedness of the state’s transportation systems for oil and gas development and production:

• improved availability and quality of data related to ongoing and forecasted drilling activities;

• development of integrated, multimodal transportation infrastructure strategies and solutions; and

• provisions for reliable, sustainable funding for proactively preparing the state’s transportation infrastructure for future drilling activities.

Economic and Social Impacts

Shale energy development primarily contributes positively to local, regional and state economies, but not all economic effects have been positive. Limited published data exist on the net economic benefits and costs of shale energy development to the institutions and residents in Texas counties and communities.

Public school districts and universities across Texas benefit substantially from the taxes and royalty revenue paid by the oil and gas industry, but these benefits are unevenly distributed.

Traffic-related issues—including increased truck traffic, traffic accidents, and traffic congestion—are of primary concern to leaders and residents in and around communities experiencing shale development.

Recommendations

The following items represent areas where knowledge of potential economic and social implications of shale development is severely limited, and should be considered as future research priorities.

• Additional research on the economic benefits and costs and associated equity issues, or “winners and losers,” in shale energy development is warranted. The broad implications of shale development for local governments and public school districts also should be investigated.

• Additional research on the underlying factors accompanying the formation of both positive and negative perceptions of shale development is needed.

• Additional research is needed to examine the potential environmental and health effects associated with varying setback distances.

• Additional research on the uneven distribution of benefits and costs associated with development is warranted.