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    Ground Gas: Sorting Out the Facts

Summary

With a background in providing independent monitoring and risk assessment services, Ground Gas Solutions Ltd. has been working with Cuadrilla Resources in developing a best practice approach to the continuous monitoring of the well pads at unconventional gas sites in the UK.

by: Drew Leifheit

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Natural Gas & LNG News, News By Country, United Kingdom, Shale Gas , Environment, Featured Articles

Ground Gas: Sorting Out the Facts

When Simon Talbot says that the US Anti-Fracking Documentary Gasland is “misguided,” he knows what he’s talking about.

An engineering geologist by training, three years ago Mr. Talbot founded Ground Gas Solutions (GGS) Ltd., an environmental geology enterprise looking to help European E&Ps in their quest to explore unconventional gas.

Of the flaming taps in Gasland he explains, “Every location will have a certain amount of naturally occurring methane  arising from organic soils, peat deposits, made ground or from carboniferous rocks. When organic rich rocks and soils are intersected by ordinary water wells, it is no surprise you get methane in the water, but the film linking what may be just natural background levels to the deeper exploration, thousands of meters below, is problematic in my view.

“The main difficulty that the US has had is they didn’t require baseline monitoring prior to beginning site operations. Without good quality baseline monitoring data, you can’t refute the claims that the local groundwater is being contaminated.”

Helping clients refute false claims is a part of GGS’ job, monitoring ground gas concentrations around drilling sites. Mr. Talbot described those sites and what his professionals do on the ground.

“The wellpads which we are monitoring are constructed to a high standard. They are located within open fields and the sites are carefully prepared and fully lined out with impermeable membranes and geotextiles before the hard core is laid down for site work.”

He continued, “We install monitoring wells around the edge of the pads, outside of the impermeable membrane, with response zones into the near surface soils to intersect the near surface aquifers. We then install monitoring devices into those monitoring wells to continually monitor the groundwater and ground-gas concentrations. The equipment we use also monitors changes in atmospheric pressure and temperature, which can affect the ground-gas flows through the ground.”

Before actually showing up at a site, said Talbot, an important element of GGS’ service is to do a baseline desk study to identify the site specific conditions and the likely local sources of ground-gas.

“All soils and rocks will have natural concentrations of methane, carbon dioxide and other gases in them and it’s important to understand what these are prior to any site operations occurring. Once the desk study is complete we install the monitoring wells and carry out the baseline monitoring to identify and characterize the ground gas and the groundwater conditions at the site prior to an operator commencing drilling and fraccing work. In addition to the continuous monitoring we take representative samples for laboratory analysis to ‘fingerprint’ the gas and identify its source. Then we do the same throughout the drilling and fraccing operations, recording the changes in ground gas concentration and taking samples for laboratory analysis.

“In that way, we have robust evidence which can be compared against the baseline, pre-drilling conditions to demonstrate that the environmental protection measures used on the site are working satisfactorily, or indeed if they are not. If a pollution event does occur, we will have early warning which we can report back to the operator so that they can take appropriate action in consultation with  the local regulators,” he said.

Via its ground gas monitoring services GGS, he explained, had been playing a crucial role between Cuadrilla Resources and regulatory authorities in the UK.

“They are the first company in the UK to do horizontal drilling and fraccing of the shale gas resources and there’s been understandable concern, both within the local community and within the regulators, as to these technologies which are new to the UK,” he said.

“We’ve worked closely with Cuadrilla in developing what we think is a best practice approach to continuous monitoring of the well pads and we’ve checked and been in regular contact with the local regulators to ensure that they are comfortable with the approach that’s taken. Our background in providing independent monitoring and risk assessment services has probably helped us in that role,” explained Mr. Talbot.

In terms of GGS’ independence and the transparency of its findings, he admitted that his company was paid by the client, not the regulators.

“Hence we are clearly associated with the operator. However, we have our own monitoring wells which only GGS have access to and we also control and operate all of the monitoring equipment at the sites. This gives us a certain amount of independence which we think is important as it demonstrates that actually this is GGS’ data and not Cuadrilla’s. This data is then  written up into independent reports that are  made available to regulators and the local community. In this way we provide confidence to the operator, the regulators and the local community that the operations are not causing contamination. 

But would GGS be willing to release findings that went against a client’s interest?

“We think that’s a very important aspect of our work and one of our policy statements makes reference to the fact that in our role we operate within a strict, professional code of conduct and we require full editorial control of the information we make available to clients and regulators,” said Mr. Talbot.

In its ground-gas monitoring work, GGS uses a special device called the “GasClam” which Mr. Talbot said he had helped develop over eight years.

“In my previous role as Director of the GMGU I was involved in collaborative research with the University of Manchester and a company called Salamander. Together, we looked at better ways for monitoring ground gasses. The conventional monitoring approach is to take periodic samples of gas from a monitoring well once a week or once a fortnight. However, the problem with that is ground gasses respond within minutes and hours to changes in atmospheric pressure, or to changes in the groundwater table and rainfall. The gasses are a fluid and flow through permeable ground quite quickly, so taking a reading once a week just gives you a snapshot in time.

“The GasClam allows for continuous monitoring,” he explained. “The actual drivers which affect the gas concentrations and the hazards associated with it are therefore much better characterized using continuous monitoring techniques and by generating continuous monitoring datasets.

“Because we are looking at the full variation over time, we’ve got a complete picture of the gas regime at a particular location, which means there aren’t any gaps in our knowledge – that is something which is apparent when you look at a conventional spot monitoring data set. At best, you only get a feel for what happens at a particular time on a particular day and you don’t know what happens between the two dates. The conventional approach can be very misleading,” he added.

Mr. Talbot said that for much of his career he had worked in both the public and private sectors, on contaminated land issues.

“At the moment GGS are providing most of its service to the unconventional petroleum market,” he said. “The rest of our work is for regulators, developers and their consultants. This latter work is mainly a troubleshooting service, looking at the monitoring and risk assessment of ground gas contamination issues. 

Given GGS’ experience in the UK, Mr. Talbot offered his advice for others exploring for unconventional gas in other parts of Europe.

“I believe that engagement with the local community is a prerequisite to ensuring the smooth operation of an exploration site, not only in providing transparent information to communities about what is being done and how the environment is being protected, but also to demonstrate the benefits for the local economy and job opportunities as well as securing local energy supplies,” he explained.

“We think the unconventional petroleum market is going to be a real game changer for Europe and we’re looking very much forward to contributing to ensure that the industry is developed in a safe and environmentally responsible way.”