Tempering The Witch's Brew: Minimising The Side-Effects Of Shale Gas Drilling

Companies involved in the oil and gas sector, particularly in the field of shale gas, are constantly faced with the issue of ensuring the technical and financial efficiency of drilling and well completions.

Regardless of whether it is horizontal well placement or water management techniques, organisations strive to find cost-effective ways of extracting the substance, which also have minimal side-effects.

Texas in particular is geologically rich in natural gas, and so is a hive of activity among drillers, including those extracting shale gas, but this means there are often unwanted side-effects for those living nearby.

Some of the practices currently being used bring about air, water and noise pollution, leading to residents complaining and subsequent controversy in the media.

In recent years, these environmental concerns have only continued to grow, particularly with activities triggered by technologies that were developed in the gas-bearing Barnett Shale in northern Texas.

Residents and local officials in the area have complained about potential threats such as methane in their water wells and benzene in the air, and these concerns are now being directed towards a new development in Texas.

Operations have begun at Eagle Ford Shale, a geological formation that outcrops at the town of Eagle Ford, near Dallas.

However, it seems that care is now being taken to anticipate and possibly minimise such impacts on the area and the people who live there, thanks to the Houston Advanced Research Center (HARC).

The non-profit institution in the Woodlands says that this is possible through coupling exploration and drilling activities with tools and procedures for preventing harmful side-effects.

For example, previously the Eagle Ford was an area that drillers wanted to avoid, but now directional drilling combined with hydraulic fracturing means that wells can be completed in the ford itself, just as many have been in the Barnett Shale.

So far the economic results are impressive where those techniques are used, with the Barnett Shale now producing around six per cent of all the natural gas in the 48 contiguous states. Meanwhile, drilling in the Haynesville Shale in Louisiana has generated approximately $5.7 billion (£3.5 billion) in new household earnings for residents, with over 57,000 jobs also created.

To address the issues of water, noise and air quality, HARC has pioneered the Environmentally Friendly Drilling (EFD) Systems Program, which takes the form of a scorecard.

According to the company, the scorecard measures the effectiveness of natural gas operators' practices in minimising the impact of drilling in environmentally sensitive areas.

In addition, it assesses operations and technologies concerning air emissions, land disturbance, water pollution, waste management, impact on biodiversity and societal issues.

Rich Haut, a senior research scientist at HARC and director of the EFD Systems Program, wrote in the Houston Chronicle that such methods will change the face of shale gas drilling.

"The scorecard methodology produces an ecological understanding of the trade-offs involved in producing energy, which can help operators plan and implement practices to manage and minimise risks," he explained.

"Operators who use new-generation rigs, low-emission engines, advanced water management systems and small land-surface footprints can potentially earn the highest five-star rating."

The expert added that the scorecard can also help to develop a comprehensive baseline study of the Eagle Ford Shale and produce a detailed profile of the region's air and water quality, soil contamination, biodiversity and economics.

With this information in hand, a consensus can be reached on the key issues that should be monitored and measured as drilling activities multiply, he explained.

Mr Haut said that the programme can be a "valuable tool" for resolving conflicts by providing the structure for stakeholders to exchange ideas, transfer technologies and "develop unbiased science for sound policy".

By deploying such technology at Eagle Ford, it is hoped that an example can be set for any future shale gas projects and ensure that both residents and oil and gas corporations alike can benefit from extraction activities.