Overview of State Pre-Drill Water Quality Testing

Transcription

1 Overview of State Pre-Drill Water Quality Testing Water/Energy Track -- Water Quality and Oil & Natural Gas Development GWPC Annual Forum 2013, Sep 23-25, St. Louis, MO Robert W. Puls, Ph.D. Director, Oklahoma Water Survey University of Oklahoma

2 Energy and Water are linked Thermoelectric cooling Hydropower Energy minerals extraction / mining Fuel Production (fossil fuels, biofuels/ethanol) Pumping, ground water, surface water Conveyance and Transport Water Treatment

3 Water and the Oil and Gas Industry (courtesy Newfield Exploration Company) Water is the most common and most heavily used fluid in the petroleum industry Water is produced along with oil and gas from nearly every well Water is used as a base fluid in production, drilling, and completion operations Water will be produced, recycled, injected, mixed, treated, and reinjected Water s use and protection are emotionally charged subjects in many communities

4 Comparison of U.S. Shale Gas Reservoirs and Major Aquifers Regional/local variations: Basin Geology and Hydrology Availability of water resources Sustainability of ground water resources 4 Source: Energy Information Administration

5 Depleted Aquifers and Major Shale Plays 10/2/2013 5

6 Climate Change Land Use Changes Population Growth Energy Demands Protection and Sustainable Management of Our Groundwater Resources is More Important than Ever 10/2/2013 6

7 Why Collect Pre-Drill Water Samples? Oil and Gas Industry, contractors Insurance; protection against claims, fines Helps identify pre-existing poor water quality Improved understanding of general water quality in play Opportunity to improve relations with landowners and community, overcome misconceptions/misunderstandings (gain social license to operate)

8 Why Collect Pre-Drill Water Samples? Private well owners In the absence of any pre-drilling characterization of the drinking water, it is difficult, if not impossible, to prove that oil & gas operations have impacted water quality It is important to know the quality of the water you are drinking How do you know if there is an impact to your water if there is nothing to compare it to Insurance against damages

9 Who Collects Pre-Drill Water Samples? Oil and Gas Industry, contractors Private well owners State regulatory agencies It is imperative that water sampling be performed by a professional who is familiar with up-to-date water sampling protocols and laboratory protocols. Otherwise the results may have little or no value.

10 Pre-Drill Water Quality Sampling Rules: Some Examples Pennsylvania Act 13 - Presumption of liability for wells within 2500 ft; no requirement for pre-drill sampling but onus on oil and gas industry Colorado New rule 609 requires oil and gas industry to collect pre-drill samples within 2640 ft Ohio SB 315 requires oil and gas industry to collect predrill samples within 300 ft of conventional well and 1500 ft for horizontal well

11 Pre-Drill Water Quality Sampling: Some Examples North Dakota ND Rules Ch requires mineral developer to collect pre-drill sampling within 2640 ft of oil and gas well, data collected less than 1 yr prior to drilling activities New York Proposed rules require oil and gas industry to sample all wells within 1000 ft or 2000 ft if none available within 1000 ft

12 Pre-Drill Water Quality Sampling: More Examples West Virginia HB 401, 22-6A-18.b Presumption of liability for private wells within 1500 ft Illinois HB rules require oil and gas industry to sample all water sources (3 times!) within 1500 ft and post completion sampling at 6, 18, and 30 months later Wyoming (draft) Up to 4 available water sources within 2640 ft with post completion sampling as well at 12 to 24 months and 36 to 48 months

13 Other Water Quality Sampling Louisiana USGS has state-wide program to assess water quality in areas of active or planned hydraulic fracturing of shale formations in north, central, and southeastern Louisiana North Carolina USGS will conduct baseline groundwater quality sampling of public and private wells and compile well records in areas of potential shale gas exploration in the Triassic Basin of Lee and Chatham Counties

14 How many wells sampled? State Sampling radius (ft) Number of Wells Timing* PA 2500 All 1 year after* No CO 2640 All to 4 max 1 year prior Yes, 2 OH 1500 All Prior to drilling No ND 2640 All 1 year prior No NY WV 1000 (2000 if necessary) 1500 (2000 if necessary) All IL 1500 All (3 samples) WY draft Prior to site disturbance All ½ year after* No Post-Drill Sampling Yes, TBD Prior to drilling Yes, All to 4 max Prior to drilling Yes, 2 *presumptive allowable interval for detection of impact 10/2/

15 What Happens to the Data? Pennsylvania : Operator provides to state Colorado and Ohio : Operator provides to domestic well owner and state North Dakota : No obvious provisions New York, Illinois, Wyoming : Operator provides to domestic well owner and state West Virginia : Operator retains; well owner retains (private well owners encouraged to test their water) 10/2/

16 Where are Samples Collected? Almost all states provide some guidance either from the state regulator, agricultural extension office (e.g. PA, OK), or state environmental agency (e.g. LA) If at all possible, water samples should be collected directly from the well column. This is often not possible as the well is sealed. Use of the permanently installed pump is then used but sampled upstream of any ancillary equipment (e.g. holding tank, pressure tank, water softener etc.) 10/2/

17 How are Samples Collected? Remarkably little information is provided on HOW to collect samples Exceptions are CO and WY Often states make references to existing published procedures, many of which are outdated If the samples are not properly collected they are almost worthless and analysis is a waste of time and money 10/2/

18 How are Samples Collected? Consistency permits comparability over time Protocols established, written, peer-reviewed standard operating procedures Transparency establishes trust among parties Documentation written, photographic 10/2/

19 How are Samples Collected? Key Issues Regional background information Homeowner interview Sampling location Preparation, calibration of instruments Bottle prep Purge rate and time Criteria for sampling initiation Site observations 10/2/

20 How are Samples Collected? Suggested References USGS Field Manual National Field Manual for the Collection of Water- Quality Data, 2006 Colorado Oil and Gas Association ( COGA-sample-analysis-Plan.pdf) ASTM (in process of drafting) 10/2/

21 Well Purging and Sampling Objectives If the objective is to obtain a representative sample of the aquifer supplying the drinking water, how the well is purged is critical Initial water will be from pipes, treatment systems, and borehole, not from the aquifer Allow as smooth, non-turbulent flow as possible Use stabilization of water quality parameters as guide to presence of formation water (e.g. ph, temperature, specific conductance) Understand borehole volume (pipes, standing water column, annular space) and remove at least one volume Measure turbidity just prior to collecting samples Ideally collect more than one pre-drill sample 10/2/

22 Potential Problems in Obtaining Representative Samples Low yield wells with long recovery times Wells with long screens or long perforation zones May have mixing of different aquifers and related water quality Poor condition of the well (usually indicated by high turbidity) Large differences in temperature between formation water and ambient air 10/2/

23 Potential Monitoring Parameters for Baseline Sampling Program *Total coliform/e-coli

24 Documentation History of complaints Existing water quality data (e.g. private wells, public wells, USGS database etc.) can be helpful to address temporal variability and aquifer heterogeneity Written and oral communications with well owner or industry rep Sampling procedures (SOPs), QA/QC docs, analytical methods Field sampling record sheets Sample type, GPS coordinates, API well #, climate conditions, equip. calibrations, field parameters, type equipment used, depth to water, well depth, decontamination procedures, etc. Visual observations, photos 10/2/

25 SUMMARY Hydraulic Fracturing together with horizontal drilling has greatly improved the efficiency and profitability for shale gas and oil resource extraction. Baseline water quality data is important for adequate assessment of potential impacts How we collect the samples is as important as how well the samples are handled and analyzed Collection of baseline data will improve trust and protect all parties Increasing number of states now requiring baseline monitoring

26 ?? QUESTIONS??