Page 404 - Fundamentals of Gas Shale Reservoirs

384 GAS SHALE ENVIRONMENTAL ISSUES AND CHALLENGES

treatment. It forms brominated by‐products that have been roughly $3.00 per barrel to dispose of it, and $7.00–$10.00
found to be carcinogenic to humans. Since these problems for it to be hauled away. That equals between $10.00 and
were highlighted, most drilling companies in Pennsylvania $13.00 for the disposal of a single barrel, which holds 42
have stopped sending their wastewater through treatment gallons of wastewater. In 2012, new energy policy proposals
plants that were unable to remove many of the contaminants were put forth in Ohio that would raise brine disposal fees
before the water was discharged into rivers. State regulators from 5 to 10 cents on in‐state waste, and from 20 cents to
and drinking water operators are also now testing more reg- $1.00 on out‐of‐state waste. Under new proposed costs, dis-
ularly for radioactive and other toxic elements in the drilling posing of liquid waste from a single well in this manner
wastewater. would cost $5,700 for in‐state waste and $57,000 for out‐of‐
The final option for disposal is shipping the wastewater to state disposal.
centralized waste treatment facilities, which are private As the cost of wastewater treatment is increased, recy-
commercial wastewater treatment operations that handle cling, where wastewater is blended with freshwater and
industrial waste. These facilities handle all the types of waste hydraulic fracturing chemicals for use in subsequent hydraulic
fluids produced from oil and gas operations and release it fracture treatments, is growing in popularity. However, there
into waterways or send it for reuse after it is processed. Even are limitations on the amounts of total dissolved solids (TDS),
with waste treatment facilities that have been designed to barium, and other contaminants that can be present for the
specifically treat the wastewater from the fracking process, waste to acceptable for reuse in hydraulic fracturing fluids
radiological components, chemicals, and toxins have been (Wilson et al., 2014). While the recycling of fracking waste is
released and later detected in freshwater sources. Proper conceptually a good thing, there is concern that the residual
sampling methodology needs to be put into place and strictly waste coming out of that process could be toxic and is not
enforced to ensure that water quality is minimally affected governed under waste regulations.
by the treatment and release of this wastewater. As local and federal regulators raise questions about
In May 2013, environmental regulators in Pennsylvania water consumption and its disposal from drilling operations,
discovered high levels of radium around the Josephine U.S. oil and natural gas producers are asking service com-
Treatment Plant discharge pipe in Indiana County (Ferrar panies to improve their handling of the millions of gallons of
et al., 2013). The levels of radioactivity found at the fluids involved in fracking an average well. Halliburton has
Josephine plant were not high enough to cause any health a stated goal for the entire oil and gas industries to use an
threat to passersby or to workers. However, radium can also average of 25% less freshwater in fracking jobs by the end of
accumulate in fish, meaning that fish in the creek ingesting 2014. Producers are implementing comprehensive water
the radioactive metal could carry higher levels than found in management plans which incorporate strategies for reducing
the water. consumption of water, reducing the loss or waste of water,
In response to tougher state requirements for wastewater improving or maintaining efficiency in the use of water, and
disposal, new facilities are being built that can handle increasing recycling and reuse of water.
wastewater treatment. In April 2013, the wastewater
treatment company Aquatech opened a new centralized
shale wastewater treatment plant in Tioga County, 18.4 GROUNDWATER CONTAMINATION
Pennsylvania (Aquatech, 2013). The new plant is equipped
to process up to 200 gallons per minute and sits in an area There are concerns that the potentially carcinogenic chemi-
central to a huge amount of shale drilling. The Aquatech cals used in the fracking process can find their way under-
site can recycle backflow and other drilling‐generated liq- ground into drinking water sources. Water and sand make
uids to filter out solid materials, disinfect, and distill the up 98–99.5% of the fluid used in hydraulic fracturing. In
water to two different levels. At the first level, or clean addition, chemical additives are used. The exact formulation
level, filtration clears water for reuse in the industry. At the varies depending on the well. Overall the concentration of
second level, or ultra‐clean level, processed water meets additives in most slickwater fracturing fluids is a relatively
state standards for general use. consistent 0.5–2% with water making up 98–99.5%.
Fully cleaning waste comes down to economics and Typical shale gas deposits are located several thousand
technical issues. Cost estimates for various methods of feet below the deepest potential sources of underground
wastewater disposal and recycling vary, depending on both drinking water. Further, the low permeability of shale rock
the reservoir in question and the information source. and other intervening formation horizons present additional
Technology exists to clean liquid waste right up to drinking impediments to the flow of fracking chemicals from target
water standards, but it is expensive, and far more costly com- zones upward into aquifers. The likelihood of water contam-
pared to buying freshwater for drilling and fracking. Industry ination as a consequence of fluids migration up through sev-
estimates that the cost to dispose of Marcellus shale fracking eral thousand feet of strata has proven to be extremely
fluids at a proper wastewater management facility are unlikely. Most agree that more likely candidates as sources