WorldWide Drilling Resource

92 APRIL 2014 WorldWide Drilling Resource ®® 1760-156 2008-1128 Methane Discovered in New York Water Wells Adapted from Information by the U.S. Geological Survey and Pennsylvania State University AnewU.S. Geological Survey (USGS) study discovered 15% of groundwater samples from 66 household wells across south-central NewYork containedmethane at levels high enough to warrant monitor- ing or mitigation. The wells were tested in 2012 to provide baseline data on methane con- centrations in groundwater in an area with nearly 2000 square miles considered favorable for Marcellus Shale gas drilling. None of the water wells tested were locat- ed within a mile of existing natural gas wells. “This study provides baseline water quality data that will be useful for decision makers, regulators, industry, and stake- holders concerned about water quality,” said USGS scientist Paul Heisig, who led the study. “It also provides a preliminary framework to help characterize the occur- rence of methane in south-central New York that can be refined as additional data are collected.” Testing also indicated methane is common in some groundwater, but sam- pling showed methane is not random in groundwater across the site. “The strong pattern of occurrence and the high vari- ability in concentrations that we found shows where we should and shouldn’t expect high methane concentrations in groundwater,” said Heisig. Methane levels varied by more than five orders of magnitude across the study area covering parts of Broome, Tioga, Chemung, Chenango, and Delaware counties. The samples most likely to contain high methane concentrations were from valley wells that tap into bedrock groundwater lying beneath glacial clay deposits. More than 50% of those sam- ples contained methane at or above the monitoring level. Like the cap on a bottle of soda, clay blocks methane gas from escaping into the atmosphere. Nearly 30% of groundwater samples from valleys tested at or above the rec- ommended monitoring level. No samples from wells in uplands exceeded moni- toring levels. Methane in valley ground- water was mostly thermogenic in origin derived over millions of years by process- es deep within the earth. In contrast, methane found in upland groundwater was mostly generated by bacteria. High concentrations of methane can be flammable or explosive in confined spaces containing oxygen and an ignition source such as an open flame or electrical spark. Mitigation typically involves venting the well casings. Adding a vent tube to the water well cap can advance the release of methane from the well and lower the concentration of dissolved methane in the water entering a dwelling. As a professional well drilling con- tractor, it is important to encourage private well owners to test their water for methane, particularly if their well is in a valley and is not a shallow sand and gravel well. Important meetings take place. The traditional TGWA bench! The Mark Duch am & Lero y fishes sol d high! This is the wa y to race goldfish! Texas Ground Water Association Convention See you next year in San Marcos! And special draw ings too! I got the winner? Too Late to Classify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