Drilling could pollute groundwater used by 90% of rural Albertans

Drilling could pollute groundwater used by 90% of rural Albertans by Hanneke Brooymans, April 30, 2007, The Edmonton Journal with files from The Canadian Press
More than 350,000 oil and gas wells have been drilled in Alberta since production began. That’s about one well for every 10 people living in the province, says the Pembina Institute report, which is to be released today. “We’ve seen the number of gas wells in total more than double, and an increasing proportion of those are for coalbed methane or for shallow gas, and therefore there’s a greater potential for impacts on fresh groundwater,” said Mary Griffiths, a senior policy analyst for the environmental think-tank. “The greater the number of wells going through shallow aquifers or producing from shallow aquifers, the greater the potential that there could be problems. … Companies also sometimes fracture a gas reservoir — pumping water, carbon dioxide or nitrogen in to crack open the rock — to improve the flow of gas to the wells. The water may contain added substances to improve the effectiveness of the process and to hold open the crack so that gas can flow more easily to the wellbore. Some landowners worry that fracturing could allow gas to migrate into the shallow groundwater that supplies their wells. In addition, there are concerns that freshwater aquifers could become contaminated by chemicals in the fracturing fluids.