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Major Sediment Runoff Affecting Chesapeake Bay – How Much From Drilling?

The one-two rainfall punch thrown by Hurricane Irene and Tropical Storm Lee landed hard on the chin of the mid-Atlantic and New England, bringing record amounts of rainfall and causing epic flooding from Washington, DC to Vermont.  Now we’re seeing one of the results: a torrent of river water laden with runoff is pouring into bays and estuaries along the Atlantic coast.  Yesterday afternoon’s MODIS/Terra satellite image shows this impact on Delaware Bay and the upper reaches of the Chesapeake Bay:

MODIS/ Terra image taken September 12, 2011, showing sediment-laden runoff (pale brown) from the Susquehanna River filling the upper reaches of the Chesapeake Bay.  

This runoff consists of sewage overflows and sediment and other contamination washing off farmer’s fields, construction sites, and impervious surfaces like roads, parking lots and rooftops.  It’s a big shot of bad news for aquatic critters and the stuff we like to eat from the Bay – oysters, rockfish and crabs – and it’s not too great either for the communities along the way that get their drinking water from these rivers and streams.   
One of our concerns is that one-third of the Bay watershed lies on top of the Marcellus Shale drilling play, and we expect tens of thousands of new construction sites in the area over the next several years as companies clear land to drill wells, install pipelines, and build support facilities.  These sites represent potential new sources of runoff and surface water contamination, and given the precarious state of health of the Bay,we think this potential needs to be seriously evaluated and, if necessary, mitigated and better regulated to ensure the Bay doesn’t suffer as this gas resource is developed.  
This photo taken by our intern Ben Pelto this weekend illustrates the problem: severe erosion and obvious runoff from one of the many miles of new gas pipeline under construction in Pennsylvania to support the shale-drilling boom. Note the silt fences down at lower right (near the small green sign that says “Wetlands Boundary”!) and the lack of any runoff control structures perpendicular to the pipeline cut as it comes down this typically steep hillside – a recipe for disaster even with a common summer cloudburst, as any trail manager could attest:
 
Erosion along new gas pipeline right-of-way in the Chesapeake Bay watershed (Susquehanna River basin), north-central Pennsylvania.  Photo taken by SkyTruth intern Ben Pelto on September 10, 2011.

 We’re also starting to see disturbing but unsurprising pictures of flooded drilling sites and beat-up, pushed-around pieces of equipment like the tanks that hold drilling mud and fracking fluid.  That’s because, unbelievably, most states allow industry to drill in high-risk floodplains.   Our friends at LightHawk are flying over the areas affected by flooding, including the Wysox Creek watershed where we collected water quality measurements earlier this summer.  When their aerial pics become available we’ll share them here, along with more from Ben’s trip this weekend.

UPDATE  9/16: see aerial pics of flooding, Marcellus Shale drilling sites, and pipeline construction (and a few beauty shots!) in the upper Susquehanna basin taken by J Henry Fair during a LightHawk overflight on Monday, September 12. 

Marcellus Shale Drilling and Chesapeake Bay Water Quality

Following up on Ben’s post Tuesday – onshore oil and natural gas drilling can impact water in different ways:

1) Water withdrawals – drilling and hydraulic fracturing (fracking) require large quantities of water. The high-volume slickwater fracking performed on Marcellus Shale gas wells can use up to 3 million gallons of water per frack.  It’s not unusual for a single well to be fracked several times; and for a single drilling location to host several wells reaching out in all directions.  Water can be brought in by tanker truckor pipeline.  The closer the water source, the cheaper it is for the operator, so often they request permission from state and local authorities to take water directly from nearby streams.  As an example, XTO Energy (a division of Exxon) is seeking permission to withdraw up to 250,000 gallons per day from Oquaga Creek in upstate New York, a small trout stream annually stocked by the state.  My father-in-law and his fly-fishing buddies know this stream personally and think this withdrawal would destroy it as a trout stream.  Pennsylvania has already issued many water withdrawal permits for drilling and other activity (map).

2) Water disposal – the fluids used for drilling and fracking contain a wide variety of potential contaminants.  Produced water — water originally held in the target geologic formation that is produced along with the gas — can contain elevated levels of dissolved salts and, in some cases, low level radioactivity.  Spills of these fluids, and leaks in the plastic liners in fluid-reserve pits on the drillsite, can contaminate surface streams and near-surface groundwater.  Standard municipal wastewater treatment facilities are not equipped to remove some of the contaminants in these fluids, so specialized treatment facilities must be built to process this wastewater before it can be released to streams and rivers.

3) Groundwater contamination – when it comes to drilling safety, the devil is in the most mundane of details. Cement, for example. Cement pumped into the bottom of the well, and sealing off the fracked intervals, is the main line of defense to prevent gas and fluids from moving where you don’t want them to go.  Poor cementing was the proximal cause of the disastrous Montara blowout and spill off Australia in 2009, and the fatal BP / Deepwater Horizon blowout and spill in the Gulf of Mexico last year.  A recent Wall Street Journal investigation revealed that problems with cementing are alarmingly common. Casing failures, corrosion, poor drilling practices and other factors can also allow unwanted fluid migration.  The end result: a growing roster of cases where drilling activity is related to the contamination of drinking water supplies across the nation.

By the way, thanks to careless use of drilling terminology by some environmentalists and politicians, a big semantic argument has broken out, focused on whether the hydraulic fracturing procedure itself is the cause of contamination. More on this topic later, but we think this argument misses the mark: fracking is the repeated pumping of fluid into the well at extremely high pressures designed to break open rock, so any weakness or flaw in the well design or construction (like a poor cement job, for example, or cheap imported steel casing) is much more likely to lead to failure in a fracked well, than it would in one of Dad’s old-fashioned unfracked wells.

By The Way, Part Deux: National energy legislation in 2005 exempted the drilling industry from disclosing the chemicals they use in fracking, making it difficult for homeowners to monitor the quality of their drinking water without spending a fortune on water analysis. ShaleTest is a new outfit that is trying to help homeowners with this.

4) Stormwater runoff contamination of surface waters – this is the unglamorous way that streams, ponds, wetlands and rivers could be impacted by drilling activity.  A drill site, after all, is essentially a concentrated construction zone several acres in size: trees and brush are cleared, the land is graded flat, gravel is trucked in and spread out to create a space for all the trucks, equipment, supplies and people needed to drill, frack and complete a well.  Access roads are built; pipelines and other utilities are installed.  All of these elements of drilling infrastructure are potential sources of muddy runoff when it rains, changing the physical and chemical properties of streams with impacts on the aquatic life and downstream water users. The construction industry in general is subject to Clean Water Act rules to control stormwater runoff, but – yes, you guessed it – the drilling industry is exempt from those rules.

Ben’s work is focused on investigating if this potential for runoff really is a measurable problem.  If so, it could complicate the decades-long, multimillion dollar effort to restore water quality in the Chesapeake Bay.  This excellent map, created by SkyTruth volunteer Dorn Moore of Greenspace GIS, shows that over one-third of the Bay’s watershed overlaps with the Marcellus Shale gas play.Assuming one drilling location per square mile, that could mean as many as 25,000 drilling sites will be built in the Bay watershed (even more as other geologic formations, like the Utica and Ithaca Shales, are targeted for drilling).

If these sites cause measurable degradation of water quality, that could be very bad news for the Bay.