Friday, August 5, 2011

British Parliament issues report on hydraulic fracturing

British Parliament issues report on hydraulic fracturing

The Energy and Climate Change Committee of the United Kingdom's House of Commons issued a report on hydraulic fracturing.  The report provides an interesting, foreign perspective on an issues that have become the subject of heated debate here in the United States.  The report includes a thorough discussion of several issues relating to hydraulic fracturing, as well as numerous specific recommendations and conclusions.  One of the Committee's conclusions is that hydraulic fracturing should be allowed to proceed in Britain:
On balance, we feel that there should not be a moratorium on the use of hydraulic fracturing in the exploitation of the UK's hydrocarbon resources, including unconventional resources such as shale gas."
The Committee analyzed both the benefits of hydraulic fracturing and the environmental concerns that have been raised.  The Committtee's report identified economic gains and decreased dependence on foreign sources of energy as being two of the benefits.  The Committee concluded that UK shale gas resources "could be considerable," though "it is unlikely that shale gas will be a 'game changer' in the UK to the same extent it has been in the U.S."  An interesting part of the report was a statement that Britain may have greater shale resources offshore than under land.
The report noted that hydraulic fracturing also has a potential environmental benefit because the process often is used to facilitate the production of natural gas, the cleanest burning of all fossil fuels ("shale gas" is simply a term for natural gas produced from shale).  The Committee stated:  "Shale gas could lead to a switch from coal to gas for electricity generation, thereby cutting carbon emissions, particularly projected emissions from developing countries."
The report acknowledged that a countervailing concern raised by some environmentalists is that there are fugitive emissions (small leaks) of gas during the production and transport of shale gas.  Fugitive emissions are a concern because the main component of natural gas is methane, and methane (like carbon dioxide) is a greenhouse gas.  The report concluded, however, that fugitive emissions can be minimized through proper regulations.  The report also noted another concern -- that production of large quantities of shale gas might distract from efforts to develop renewable sources of energy.
But the main environmental concern that people express is a fear that hydraulic fracturing might harm the quality of underground sources of drinking water.  On this issue, the UK report reached conclusions similar to those stated previously in this blog.  The report noted that most shale formations are thousands of feet below drinking water aquifers, and that the fractures created by hydraulic fracturing are much shorter in length.  That leaves two other potential mechanisms for contamination to occur.  One would be for hydraulically-induced fractures to link with natural faults or fractures, leading to a pathway between the formation being fractured and a drinking water aquifer.  But most analysts in the United States think this is very unlikely, and the Committee seemed to agree.
The general consensus is that, if contamination were to occur, it likely would be as a result of the other potential mechanism for contamination -- a well construction failure.  Most oil and gas wells, including both those that are hydraulically fractured and those that are not, are drilled to formations that are located deeper beneath the surface than drinking water aquifers are.  Oil or gas wells pass through the drinking water aquifer, and casing and cementing of the well are used to seal the drinking water aquifer from deeper formations.  Such casing and cementing has been done on millions of wells.  The UK report stated:
There is no evidence that the hydraulic fracturing process poses any risk to underground water aquifers provided that the well-casing is intact before the process commences.  Rather the risks of water contamination are due to issues of well integrity, and are no different than concerns encountered during the extraction of oil or gas from conventional reservoirs."
For that reason, the report concluded that care should be given to well construction standards and inspection.  The report expressed a belief that Britain's existing regulations for well construction are adequate.
Another issue of occasional concern in the United States is water supply.  Typically, a few million gallons of water are used in fracturing an oil or gas well drilled into a shale formation.  That amount is fairly modest compared to some other industrial and agricultural uses.  Nevertheless, this amount of water use can put a strain on supplies in areas that already are facing water shortages.  The UK report stated that water supply generally should not be a problem if fracturing is performed in Britain, but that fracturing "could challenge resources in regions already experiencing water stress."
The report also weighed-in on the issue of whether regulations should require that the composition of fracturing water be disclosed.  That has been a hot issue in the United States.  The UK report endorsed some reporting, but it is not clear whether the report meant to support the disclosure of the specific chemical compounds used.  The report said that well operators should report the volume of fracturing water used, as well as the "type" of chemicals used, and the concentrations.  In the debate within the United States about disclosure requirements, when people refer to the "type" of additive they often are referring to the functional category of an additive -- that is, whether the additive is a biocide, corrosion inhibitor, friction reducer, etc. -- rather than the identity of the specific chemical compound.  It is not immediately clear whether this is what the report meant, or whether it was advocating that specific chemical compounds be identified.
In addition, the report discussed the possibility of spills of fracturing fluid, and such localized effects as noise and traffic that can result from increased drilling activity, and how those concerns can be addressed.
The report contains two volumes.  The first contains the narrative report, plus a transcript of questions and answers from hearings.  The second contains written materials presented by various individuals and organizations, including environmental groups, trade groups, and companies.

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