Study of Oil and Gas Extraction

June 10, 2019

EPA recently published a draft report on the Study of Oil and Gas Extraction Wastewater Management Under the Clean Water Act.  EPA states that they “conducted a study evaluating management of produced waters from onshore oil and gas extraction activities. The goal of this study was to better understand produced water generation, management, and disposal options at the regional, state and local levels for both conventional and unconventional onshore oil and gas extraction. Although the EPA looked at a variety of alternatives for reuse of produced water, the EPA’s main purpose for their study was to evaluate different approaches to manage oil and gas extraction which wastewaters have generated at onshore facilities. One of the approaches studied included the assessment of different technologies for facilities that would ultimately treat and discharge oil and gas extraction wastewaters, which, in turn, would produce surface waters. Surface waters are regulated under the Clean Water Act (CWA) (for purposes of this report, “surface waters”). A second goal was to better understand any potential need for, and any concerns over, additional discharge options under the CWA for onshore oil and gas wastewater”.

Waste streams addressed by the guidelines for 40 CFR Part 435 for the onshore category include:

(1).         Drill cuttings, which are the particles generated by drilling into subsurface geologic formations and carried out from the wellbore with the drilling fluid.

(2).         Drilling fluid or mud, which are the circulating fluid used in the rotary drilling of wells to clean and condition the hole and to counterbalance formation pressure.

(3).         Produced sand, which are the slurried particles used in hydraulic fracturing, the accumulated formation sands, and scales particles generated during production. Produced sand also includes desander discharge from the produced water waste stream, and blowdown of the water phase from the produced water treating system.

(4).         Produced water, which are the fluids brought up from the hydrocarbon-bearing strata during the extraction of oil and gas, and includes, where present, formation water, injection water, and any chemicals added downhole or during the oil/water separation process.

EPA has worked closely with the regulated and interested stakeholders in preparing this report.  EPA hopes to receive additional input from the public in the following areas:

(1).         What non-regulatory steps should EPA take to encourage re-use/recycle of produced water?

(2).         Considering the cost of transporting and treating produced water, would revising 40 CFR Part 435 to allow for broader discharge of produced water shift the manner in which produced water is currently handled?

(3).         Should EPA continue to distinguish between discharges from onshore oil and gas facilities located East and West of the 98th meridian or establish a national policy irrespective of geographic location?

(4).         What steps could EPA take that might incent re-use of produced water within and outside of the oilfield?

EPA has requested comments from the public by July 1, 2019. Comments can be submitted via email at,  A copy of the draft report can be found here,


Contributed by Todd Perry, P.G., Principal