Leak shuts fracking-water storage pond; Talisman says environmental risks are low by Wendy STueck, October 30, 2013, The Globe and Mail
A Talisman Energy storage pond for water used in the hydraulic fracturing process has been taken out of service after inspectors detected a leak. Routine inspections uncovered problems in July with the double liner at the pond – one of five that the company operates in the Farrell Creek area of the Montney gas play in northeastern B.C., Talisman Canada spokeswoman Berta Gomez said on Wednesday. The pond was taken out of service and the incident was reported to the Oil and Gas Commission, which is overseeing remediation at the site.
Preliminary tests have shown leaching of chemicals into nearby soil and groundwater, but the amounts are small and are not considered a threat to human health or the environment, Ms. Gomez said. An outside company has been engaged to assess the site and conduct more tests. The pond has been drained and soil is being excavated and removed for disposal. “The initial results that we have indicate that any impact on the soil is very localized,” Ms. Gomez said, adding that groundwater tests have shown similar results. “At this point based on the analysis we have done, this does not pose any significant risk to the environment, to people, to animals or anything else.” The groundwater in the area is not used for human consumption, she added. The pond, known as Pond A, is 80 metres long by 60 metres wide and about 12 metres deep. Energy companies use the containment structures to store “produced” or flowback water – which contains small amounts of chemicals used in fracking, including benzene and methanol – to re-use at other drilling sites. Talisman uses the ponds to reduce the amount of fresh water it needs, Ms. Gomez said. The pond had been operating for two years and the company said it is not aware of any similar problem before.
The Oil and Gas Commission is investigating the incident. It has not yet been determined how much fluid leaked, but about 4,600 cubic metres of soil has been excavated so far with another 300 cubic metres expected to be removed, OGC spokesman Hardy Friedrich said. The company was ordered to drain the pond, remove the liners and excavate the soil. [Emphasis added]
[Refer also to:
A Primer for Understanding Canadian Shale Gas – Energy Briefing Note by National Energy Board, November 2009. Frac water often contains chemical additives to help carry the proppant and may become enriched in salts after being injected into shale formations. Therefore, frac water that is recovered during natural gas production must be either treated or disposed of in a safe manner. … Flow-back water is infrequently reused in other fracs because of the potential for corrosion or scaling, where the dissolved salts may precipitate out of the water and clog parts of the well or the formation. ]