Whether or not Allegheny College chooses to explore natural gas development on or beneath Bousson, it is important to be very aware of the potential risks and impacts. New regulations and improvements in drilling technologies and techniques should reduce the incidence of environmental and safety accidents, however only time will tell. Regardless of an individual landowner’s decision regarding leasing, it appears highly likely that deep well drilling and hydraulic fracturing will be coming to Crawford and the surrounding counties. Pollution does not respect property lines so even if Allegheny does not develop, we may still experience water or soil contamination, negative changes in air quality, as well as wildlife disruption at Bousson.
Water and Soil Contamination
Perhaps the largest public concerns related to deep shale drilling and hydraulic fracturing are the potential opportunities for contamination of water sources. There are two main creeks on the Bousson Environmental Research Reserve, Little Sugar and Sandy Run, along with an extensive wetland area. Little Sugar and Sandy Run empty into French Creek, part of the Ohio River watershed and renowned as one of the most important streams in eastern North America: one that is rich in biological diversity and has outstanding water quality. French Creek is used by many Allegheny departments as a research laboratory. In addition, the acclaimed Creek Connections program, based at Allegheny College, collaborates with dozens of regional middle and high schools to provide an authentic natural science research experience and an appreciation for local waterways. The Nature Conservancy has identified French Creek as a globally significant watershed.
While regulations are in place to protect surface waters and groundwater, there are still many and diverse examples of contamination and degraded waterways and drinking water due to Marcellus Shale operations in recent years. These range from the dramatic flaming of tap water to a more quiet accumulation of pollutants in watersheds to the potential long-term migration of pollutants into groundwater drinking aquifers. Water can be contaminated by the chemicals using in fracturing fluid, many of which are linked to cancer, organ damage, nervous system disorders and birth defects; natural gas or methane migration to aquifers; and the many wastes produced in the drilling process.
Not only do drilling sites have the potential to impact natural water resources, but they also produce polluting solid wastes which must be disposed of properly to prevent contamination of soil and water either at drilling sites or at landfills. Solid wastes include drill cuttings, drill mud, and flocculated bentonites from the drilling process as well as dried cake residue created from evaporated brine, frac fluid and flowback water processed in on-site holding ponds.
For a detailed account of Water’s Journey Through the Shale Gas Drilling Process in the Mid-Atlantic Region read Penn State Extension’s publication.
Water Extraction: First, since the hydraulic fracturing of each well requires such a large quantity of water, there must be a source for extraction either on-site or remotely. Regardless of where the water is sourced, extraction in such volume threatens water levels and aquatic ecosystems. If the water is sourced remotely, then it must be trucked to the well pad causing impacts to local roads and air quality.
Well casings: Early Marcellus shale drilling operations in eastern Pennsylvania were fraught with water contamination due to Insufficient or faulty well construction, casing, and cementing. State regulations have been updated since then and time will tell if the problems have been solved. Click on the image below of a “Cross-Section of a Typical Marcellus Well,” courtesy of Penn State University’s Marcellus Center for Outreach and Research (MCOR). Water contaminations in the past have occurred from flaws in the well casing which allowed frac fluid or natural gas and methane to migrate through natural geological fractures to groundwater sources, including those tapped for individual homeowners’ drinking wells.
Hydraulic Fracturing: Operations at the well pad are another source of water contamination. Water is mixed with the drilling company’s proprietary blend of chemicals and proppants in preparation for hydraulic fracturing. Spills or leaks of these chemicals can potentially flow into surface waterways or percolate into groundwater. Spills or leaks of diesel fuel from trucks or generators can also impact water. When pollutants enter surface waters, aquatic ecosystems are potentially impacted by sudden fish kills or more gradual bioaccumulation of toxins within the food web. Wildlife and livestock that depend on natural surface waters as an drinking source also intake the contaminants and may pass them on to human consumers of animal products.
Flowback Water Disposal: When a well is hydraulically fractured, 60-70% of the water and chemicals used in the process remain underground, while 30-40% returns to the surface as flowback. Both the fluids that remain underground and the flowback contain the mixture of fracking chemicals as well as dissolved salts and naturally occurring radioactive elements and heavy metals dislodged from the shale deposits during fracturing. Flowback fluids must be disposed of by either deep injection on site or remotely, treatment at a water treatment facility, or through the use of holding ponds on site. Transporting the waste water away from the drilling site creates opportunities for spills during transit. In addition, injection of fluids has been linked to small earthquakes and creates the possibility of groundwater contamination at an additional site. On-site holding ponds are susceptible to punctures in plastic liners or overflows after heavy rains, creating another pollutant source at the well pad. Some drilling companies also use flowback water as a sprayed dust suppressant on roads. The chemicals and salts can then easily enter surface waters during rain events.
The EPA is currently working on a study of potential human impacts of natural gas drilling. The agency released a first progress report in late 2012, while the final draft report is not expected to be released until 2014. You can also listen to a podcast about a recent study in southwestern PA to assess the health of women living near gas wells.
Water: Primary concern for negative human health impacts has centered upon the contamination of water by the means described above. Since many of the chemicals used in the hydraulic fracturing process are known carcinogens, there is concern about the long term effects of exposure. Drilling occurs within watersheds for municipal water and therefore has the potential to impact thousands of people rather than just the individual landowner’s private wells. Any leaks, spills or accidents in Crawford County would not only impact our local French Creek Watershed, but also the larger downstream watersheds of the Ohio River Valley and Mississippi River watershed and all those who rely on these systems for drinking water and fisheries.
While drilling companies are required to report the individual ingredients used at a drilling operation, they are not required to make actual formulas of their fracturing fluid public. This is considered proprietary information, but leaves local emergency response teams ill-informed and ill-equipped to deal with accidents.
Air Quality: A variety of air quality issues associated with drilling operations also have the potential to negatively impact human health, particularly for those who live near a drilling site. High levels of benzene, ground level ozone and non-methane hydrocarbons have been found in the air around hydraulically fractured sites. Emissions from truck traffic and diesel powered compressors and generators at well pads also impact air quality. Finally, the practice of spraying flowback water on roads to limit dust can cause the chemicals to become airborne and therefore harmful to the respiratory tracts of residents.
Methane Migration: Another dramatic health concern has become infamous in the video of a man lighting his tap water on fire. Flammable water is caused by methane migration, sometimes linked to drilling operations, and causes serious health and safety problems. While methane migration does occur naturally as underground methane slowly travels to the surface through natural fractures in geological formations, natural gas drilling can speed up the process and cause dramatic flammable faucets and geysers as well as dangerous methane accumulating in homes. Methane migration linked to drilling is caused by faulty well casings or unidentified nearby abandoned wells. Methane can dissolve in water and therefore contaminate drinking water wells. The migrating methane can also enter a building through cracks in foundations and basement walls, along pipes, through water wells, or other openings. If methane builds up in a home, a dangerous explosion hazard is created.
Habitat Destruction and Fragmentation
Not only are there potential environmental and human health impacts from drilling operations, but there is concern about habitat destruction and fragmentation as well. Landowners can stipulate measures in their leasing contracts that would help to minimize these impacts, but drilling companies also need to consider their operations in a region from a holistic standpoint if the unique forests, wetlands, and wildlife populations of Pennsylvania and elsewhere are to be preserved. Landscape and habitat impacts can originate from the creation of well pads, roads, pipelines and compression stations, as well as the noise, light, activity and pollution associated with the drilling operation once underway. Many conservation and sportsmen organizations have concerns about deep shale drilling operations and the sufficiency of regulations. The Nature Conservancy of Pennsylvania has concerns about wildlife fragmentation. Trout Unlimited is concerned about stream quality that could impact fish populations and health. The Sportsmen Alliance for Marcellus Conservation is concerned about impacts on hunting, fishing and trapping and advocates for additional regulation to protect fish and wildlife and therefore the sporting traditions of Pennsylvania.
Well pads: While every drilling site is unique, a typical deep shale well pad requires 4-6 acres to be cleared for equipment, and operations. If the site of the well pad was previously forested, tree and understory removal is necessary, with potential habitat loss, soil compaction and subsequent erosion and sedimentation resulting. If the site of the well pad was previously cleared, a landowner might lose valuable acreage of cropland. A leasing contract should require the drilling company to restore the site after operations cease, but landowners should also consider what additional stipulations, such as the use of native grasses for reseeding, will most responsibly and naturally restore the site over time.
Roads: Depending on where well pad(s) are situated on a property, drilling companies also must establish access roads. This could result in additional logging, soil compaction, erosion and wildlife fragmentation. Some landowners have also experienced an increase in recreational four wheeler traffic on their property once the roads increase access.
Pipelines and Compressor Stations: Once drilling commences, pipelines are necessary to transport the natural gas, condensates, and/or oil from the well pad. First, gathering lines take the gas to a transport line, which then feed into “mid-stream” or “interstate” lines which take the gas to market. The Pennsylvania Chapter of the Nature Conservancy estimates that between 12,000 to 27,000 new miles of gathering pipeline alone will be needed to transport the Marcellus Shale gas yield due to the large number of expected well sites and the anticipation of high volumes of gas. Constructing pipelines requires clearing of forests and disturbing significant amounts of soil to bury the lines. If not managed properly, this can lead to erosion and sedimentation and negatively affect local waterways. After construction, cleared right of ways must be maintained along the pipelines for monitoring and maintenance, leaving a permanent fragmentation feature across natural habitats. Wildlife fragmentation may have negative impacts on migratory bird patterns as well as other fauna. Many environmentalists worry that the cleared areas around pipelines will create an “edge effect” in which some species which prefer habitats with full canopy, such as interior forest birds, amphibians, and certain wild flowers will see their habitat diminished. In addition, fragmentation increases susceptibility to invasive species.
In conjunction with pipelines, compressor stations, or pumping stations, are also required to pressurize the gas at intervals within the pipeline and keep it moving along. Compressor station sites often occupy about 5 acres of cleared land and noise pollution and air emissions result from their operations.
Noise, Light, Activity: Drilling operations have periods of concentrated activity that can be disruptive to wildlife as well as local residents. Noise from generators, trucks, and the drilling; lights to allow 24/7 work; and a significant increase in traffic can also disturb wildlife habits.
Pollution: Drilling operations result in air emissions from truck traffic and diesel generators at the well pad. The resulting ground level ozone and other emissions damage vegetation resulting in decreased crop yields and declined forest health and productivity, due to increasing susceptibility to insects, weather, competition, disease and pollution.