Production of natural gas from shale reservoirs is approaching 30% of total natural gas production in the US. Today, the US is not only self-sufficient in natural gas, but it has enough natural gas for the rest of this century on the basis of current demand. In fact, the industry could produce much more natural gas than it does now if demand increases. In early 2011, the US Department of Energy set up a Secretary of Energy Advisory Board (SEAB) subcommittee to evaluate how shale gas reservoirs could be developed safely. The secretary requested that within 90 days of its first meeting it report to SEAB on the “immediate steps that can be taken to improve the safety and environmental performance of fracturing.” In August 2011, the subcommittee issued its first report containing 20 recommendations. In November 2011, the subcommittee issued its final report with a status on the implementation of all 20 of its recommendations. Both reports and tens of thousands of related documents on the subject can be found and downloaded at Shalegas.energy.gov.

Recommendations

Some of the DOE’s major recommendations include:

Improving casing and cementing procedures to isolate the gas-producing zone from overlaying formations and potable aquifers. Loss of well integrity is the result of poor well completion or poor production-pressure management;

Controlling the entire lifecycle of the water used from acquisition to disposal. All water flows should be tracked and reported quantitatively throughout the process;

Limiting water use by controlling vertical fracture growth. Periodic direct measurement of earth stresses and the microseismic monitoring of water and additive needs eliminates rogue methane migration and saves production money;

Using multiwell drilling pads to monitor processes and minimize truck traffic and surplus road construction. The use of mats, catchments, groundwater monitors, and surface water buffers should be industry standard in shale gas production;

Declaring unique and/or sensitive areas off-limits to drilling. Such an abundance of natural gas reserves has come from the fracing revolution that there is no need to drill beneath protected urban or wilderness areas. This recommendation is one of the most difficult to apply as the owners of the minerals in such areas have the right to produce those minerals. Fortunately, with long-reach horizontal drilling, many urban areas can be developed from remote pad sites with appropriate controls; and

Mitigating noise, air, and visual pollution. Conversion from diesel to natural gas or electrical power for equipment fuel is an important first step and can be substantially accelerated.

Air quality and lifestyle disruption

In addition to the familiar concerns about water quality, the impact of hydraulic fracturing on air quality can be challenging. The full cycle of shale gas production – from initial exploration through the capture and transport of the natural gas and final site remediation – can result in the emission of some methane and diesel exhaust from the trucks and drilling rigs required for drilling and completing the wells. Methane is the pollutant that requires the most attention. Some opponents would rather see the methane flared than simply released into the atmosphere. However, most operators would rather not flare methane because it is a commodity. One problem that surfaced during the SEAB subcommittee fact-finding was the problem of “lifestyle disruption.” Most people, especially in the Northeast US, do not like the truck traffic, the compressor stations, the gas pipelines, and other activities that disrupt their day-to-day lives. These are issues the industry can and should address by doing things such as drilling multiple wells from a single pad and converting drilling rigs and trucks to burn natural gas for fuel rather than diesel. Additional suggestions include:

Enlisting a subset of producers in different basins to design and implement measurement systems to col- lect comprehensive methane and other air emissions data from shale gas operations and make those data publicly available;

Launching a federal interagency planning effort to acquire data and analyze the overall greenhouse gas footprint of shale gas operations throughout the lifecycle of natural gas use in comparison to other fuels; and

Encouraging shale gas production companies and regulators to expand efforts to reduce air emissions using proven technologies and practices.

The energy bonanza that comes from the hydraulic fracturing of horizontal wells drilled in shale rock has changed America’s energy outlook dramatically in less than a decade. Shale gas producers need to quickly define and enforce best practices to guarantee public confidence in their stewardship of this technology revolution that could lead to energy security for the US.