By Matt Kelso, Manager of Data & Technology
According to data published by the Pennsylvania Department of Environmental Protection (DEP), Pennsylvania’s unconventional oil and gas waste that was generated in the first half of 2015 found its way to treatment facilities, disposal wells, and landfills in eight different states. While the majority of the waste stayed in-state, neighboring Ohio, New York, and West Virginia all received significant quantities of both solid and liquid waste, and additional disposals were made in the non-contiguous states of Michigan, Texas, Utah, and Idaho.
Waste generated by Pennsylvania’s unconventional oil and gas wells was disposed of in a variety of ways and over a large geographic area. Click on a facility to learn more, or zoom in to access waste generated by individual wells. Click here to access the full screen map with a legend and additional controls.
Unconventional drillers in the state are now required to report production data monthly, rather than in six month increments, but waste quantities generated by the wells is still supposed to be reported biannually. However, a small number of operators have been reporting waste monthly, as well, and those figures have been included in this analysis, after spot-checking for duplication. Each record includes data on how the waste was processed and where it was shipped, so we were able to map the receiving facilities as well, and aggregate their waste totals.
Types of Waste
There are eight types of waste detailed in the Pennsylvania data, including:
- Basic Sediment (Barrels) – Impurities that accompany the desired product
- Drill Cuttings (Tons) – Broken bits of rock produced during the drilling process
- Flowback Fracturing Sand (Tons) – Sand used to prop open cracks made during hydraulic fracturing that return to the surface
- Fracing Fluid Waste (Barrels) – Fluid pumped into the well for hydraulic fracturing that returns to the surface. This includes chemicals that were added to the well.
- Produced Fluid (Barrels) – Naturally occurring brines encountered during drilling that contain various contaminants, which are often toxic or radioactive
- Servicing Fluid (Barrels) – Various other fluids used in the drilling process
- Spent Lubricant (Barrels) – Oils used in engines as lubricants
- General O&G Waste (Tons) – Solid waste types other than drill cuttings or fracturing sand
For the sake of simplicity, this analysis will at times aggregate the waste types into two categories, with all types reporting in tons as solid waste, while those listed in 42 gallon barrels will be considered liquid waste.
This PA waste gets disposed of in a variety of ways. About 93 percent of all solid waste ends up in landfills. 29 of the 58 operators reporting waste during this cycle reported drill cuttings. In a separate report, the DEP has records for unconventional wells drilled by 28 different operators during the same time frame, so these results seem reasonable, since drill cuttings are generated during the drilling process, whereas other types of waste are produced throughout the life cycle of the well.
Statewide, there over 596,000 tons of drill cuttings produced during a period which saw 422 wells spudded, an average of 1,412 tons of cuttings per well. Not all operators generated the same amount of cuttings per well, however. Vantage Energy reports 3,089 tons of cuttings per well, while Hilcorp Energy manages to average just 119 tons over 23 wells drilled in the six month period. It is worth noting that some wells that were spudded just prior to the reporting period likely still generated drill cuttings during the six months in question, and some wells spudded during the cycle will continue to produce cuttings into the next one.
In terms of liquid waste, nearly two thirds of the amount reported is reused for purposes other than road spreading. This is, unfortunately, a dead end in terms of being able to follow the waste stream in the data, as there are no facilities associated with the 13.8 million barrels of waste that falls into this category. 225,000 barrels are specified as being reused for hydraulic fracturing, while the remainder is simply destined for, “Reuse without processing at a permitted facility.”
The amount used for road spreading, 147 barrels, is relatively small, and all of this waste is reported as going to private roads in Greene County. The total amount of liquid waste produced in the six month period is almost 879 million gallons, or enough to fill 1,331 Olympic-sized swimming pools.
PA Waste Receiving Facilities
Altogether, we know where roughly 7 million of the nearly 21 million barrels of reported liquid waste wound up, as well as 640,000 of the 647,000 tons of solid waste. The top ten destinations for each waste type are as follows:
Six of the top destinations for liquid waste were located in-state, while seven of the top ten facilities for solid waste stayed in Pennsylvania. The only facility to appear on both lists is Patriot Water Treatment in Warren, Ohio.