By Jake Lemon & Josh Wood, TU Eastern Shale Gas Monitoring Program
Pennsylvania has a long history of hydrocarbon extraction that extends back to the early 1800s, including coal, oil and gas. Horizontal drilling and hydraulic fracturing are simply the most recent additions to these many extraction techniques.
Because Pennsylvania has an abundance of hydrocarbons, the state is now home to more than 100,000 abandoned coal mines, more than 400,000 abandoned oil and gas wells, and now tens of thousands of active unconventional shale gas wells.
Cases of methane migration into water supplies have been observed as a result of extraction, and in some cases, abandonment of these wells and mines.
Now, Trout Unlimited and Penn State are working to identify where that’s happening – with an assist from anglers, who know Pennsylvania’s streams better than anyone.
Methane migration is a concern for many reasons. Methane is a stronger greenhouse gas than carbon dioxide, and it is an explosion hazard.
In certain cases, it can create anoxic (oxygen-depleted) groundwater conditions that can cause dissolution of metals into water and formation of undesirable gases such as hydrogen sulfide. Introduction of metals and other dissolved solids into groundwater can pollute streams and harm the fish that live in them.
TU volunteers have been helping Penn State researchers document background methane concentrations and identify streams with elevated methane levels. This information is useful to identify contamination events resulting from hydrocarbon extraction.
Volunteers trained in sample collections procedures are greatly expanding the capacity for data collection by sampling their local streams and rivers.
Seeps – or areas where groundwater comes directly to the surface – represent natural pathways of groundwater up flow.
When iron or other metals stain these seeps, it can indicate that deeper, contaminated waters are interacting with near-surface groundwater. Contaminants from oil and gas drilling or abandoned mine drainage can sometimes find their way into these natural pathways and cause these iron precipitates.
Natural processes can also be responsible for metals emerging from these seeps. Isotope analysis can often be used to differentiate between natural thermogenic methane, input from wetlands, or methane contamination resulting from hydrocarbon extraction.
Samples collected by a TU member in Moshannon State Forest near a seep were found to have elevated methane and metal concentrations. Penn State researchers are currently working to determine the source.
In order to target sampling to these high-risk areas, TU and Penn State are asking for your help to identify other seep areas that may be worth sampling.
We are interested in photos and GPS co-ordinates for groundwater seeps exhibiting a “rusty” color associated with oxidized iron.
If you know of a location such as this on one of your local streams, please contact Jake Lemon at jlemon@tu.org.
If you don’t have a GPS device, you can download GPS apps such as Easy GPS or GPS Essentials to your smartphone. These will typically work even when you are outside a cell service area.
Volunteers who find seeps are also welcome to assist us with sampling those streams.
For more information on the program, visit the TU Eastern Shale Gas Monitoring Program webpage.
(Photo: Groundwater seep in Moshannon State Forest.)
(Reprinted from the Summer newsletter from the PA Council of Trout Unlimited. Click Here to sign up for your own copy (top of page).)
(Photo: Groundwater seep in Moshannon State Forest.)
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