What Happened at Fernow
Fracturing Chemicals
When we first started our oil and gas research September 2008, we thought fracturing just required water, sand and possibly acid. From the previous chapter we've seen wells can be acidized with mostly acid and very little water. More commonly wells locally are now fractured with either gel (crosslinked or other type of gel) or nitrogen foam.
The Berry Energy well at the Fernow Experimental Forest seems to have been fractured using acid pretreatment and water and sand. Additives were used to satisfy a variety of needs. Crosslinked gel, or a linear gel, increases the water's viscosity so that the gel and water mixture more easily pulls the sand along with it as it's being pumped under high pressure down the mile deep hole in the ground.
Because there is a gel there has to be a breaker additive to return the gel mixture to a lower viscosity. This is important because gel would clog the newly fractured formation. Too much gel remaining would also keep water in the formation. In either case gas won't be allowed to flow freely.
A friction reducer is sometimes used because shoving sand and water slurry such a distance through a relatively small hole is a lot of work otherwise. A corrosion inhibitor is used to prevent water or other chemicals from adversely affecting pipe, fittings or production equipment. And, lastly, since some of the additives are made from organic substances (such as cellulose) and because there's so much water, bacteria or algae can grow which can snarl up the works. Glutaraldehyde is a biocide that we've written about which supposedly readily biodegrades. Another chemical, 2,2-dibromo-3-nitrilopropionamide (DBNPA), is also used as a biocide and doesn't biodegrade as readily.
Biocides are an obvious health concern as are some of the chemicals used to make fracturing additives such as ethylene glycol in crosslinked gel. West Virginia doesn't allow diesel or kerosene, alone or when used as additives, to be dumped in a drilling waste pit. The issue is that many linear gels (using a petroleum hydrocarbon base) are not clearly identified by the manufacturer as using diesel or kerosene, are identified under other names which are synonyms for diesel or kerosene, or use substances identified as "proprietary."
We have no idea how much unused fracturing chemicals or after-the-fracture flowback entered the Berry Energy pit. Since the DMR showed 100,000 gallons landsprayed and a little over 100,000 gallons of water were used to fracture the two formations, it's entirely possible that what was landsprayed at Fernow was spent fracturing fluid. That would help explain the relatively high chlorides found in the pit.
Generally additives for fracturing are used in modest amounts, several gallons of additive per 1,000 gallons of water. Modest but not negligible amounts. Unfortunately, the state's testing requirements won't indicate the presence of these chemicals and we're not sure what sort of testing program would need to be initiated to do this. We know that there is no easy way to test for glutaraldehyde.
The one fracturing chemical used in large amounts at the Berry Energy well was 15% hydrochloric acid. We believe the low pH of the liquids in the inadvertent flowback release was a factor in vegetation death near the pad. We also believe that spent hydrochloric acid could have been a major source for the chlorides in the waste pit, a major cause of vegetation death during the flowback incident and later during landspraying.
There are several good online sources of information about fracturing chemicals and health risks. The 2004 EPA coalbed methane study is seriously flawed, but its description of additives and chemicals and fracturing chemical remnants remaining in (or beyond) the formation after fracturing are useful. The 2000 EPA Associated Waste Report: Completion and Workover Wastes has a good description of the drilling and fracturing process and an important discussion of the range and toxicity of wastes.
Go to the next chapter, What Happened at Fernow.
What Happened at Fernow
Landspraying
Fernow Experimental Forest
Discharge Monitoring Report
Chloride Load
SAR
Liming the Pit
A Short History of Fracturing
Fracturing Chemicals
What Happened at Fernow
Recommendations & Sources
Gas Well Study is the examination of natural gas wells in West Virginia.
Underground Injection Control Class 2 Wells
These wells are used either for the disposal of oil and gas liquid waste or for the enhanced recovery of oil or natural gas.
Gas Well Study Site Visits
Annual reports, environmental assessments, and individual well information.
YouTube Videos
Select videos from the Gas Well Study YouTube channel.
What Happened at Fernow
An investigation into what caused the vegetation death in the land application area after landspraying hydraulic fracture flowback waste.
The Spill at Buckeye Creek
An investigation into a spill from a Marcellus well site into Buckeye Creek in Doddridge county.
The Details
Plunger Lift Technology on Gas Wells
Fluids Brought to the Surface during Production
Plugging a Well
How To Read a Lab Report
Information the Completion Report Provides
Casing and Cementing