Wyoming requires groundwater testing before and after drilling

On November 12, 2013, the Wyoming Oil and Gas Conservation Commission (WOGCC) approved regulations to be effective on March 1, 2014, that will require oil and gas operators to conduct testing of water sources before and after drilling a well. With an Application for Permit to Drill or Deepen a Well, operators must identify all water sources within one-half mile of the surface location of the proposed oil or gas well and submit a plan to sample, analyze, and monitor at least four of these groundwater sources.

The plan must include “initial baseline water sampling and testing followed by a series of subsequent sampling and testing after setting the production casing or liner.” The baseline sampling must be done within a year prior to drilling. The first subsequent testing of the same water sources must be done within 12 to 24 months after installation of the production casing or liner, and the second subsequent sample to be taken within 36 to 48 months after the installation of the production casing or liner (but no less than 24 months after the first subsequent sample).

The new rule sets out a sampling and analysis protocol, requiring identification of various constituents including dissolved gases (methane, ethane, propane), alkalines, calcium, iron, potassium, sodium, and BTEX compounds (benzene, toluene, ethylbenzene and xylenes). The operator is required to provide the results of all analytical tests to the WOGCC and to the water source owner within 90 days of the sampling. If, however, the tests show any increases in thermogenic gas, methane, or BTEX compounds above certain thresholds, the operator must “provide verbal and written notification” within 24 hours to the Supervisor of the WOGCC, the Director of the Department of Environmental Quality, and the water source owner.

According to the rule, these sampling results “shall not create a presumption of or against liability, fault, or causation against the owner or operator of a well or multi-well pad who conducted the sampling, or on whose behalf sampling was conducted by a third-party. The admissibility and probative value of any such sampling that results in an administrative or judicial proceeding shall be determined by the presiding body according to applicable administrative, civil, or evidentiary rules.”

With this rule, Wyoming becomes the second state to require groundwater testing and monitoring both before and after drilling. Colorado was the first state, with its regulation taking effect in January 2013. Colorado requires operators to collect up to four water samples from aquifers, water wells, and other water sources within one-half mile of the oil or gas well site before the well is drilled and within 72 months after the well is placed in operation.


This post was written by Barclay Nicholson (barclay.nicholson@nortonrosefulbright.com or 713.651.3662) from Norton Rose Fulbright's Energy Practice Group.