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BASELINE WATER QUALITY SAMPLING IN SHALE GAS EXPLORATION AND PRODUCTION AREAS 1
BASELINE WATER QUALITY SAMPLING IN SHALE GAS EXPLORATION AND PRODUCTION AREAS
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Scott Haas, Debby McElreath and Mark Hollingsworth Chesapeake Operating, Inc., Oklahoma City, OK and SAIC Presented at GWPC 2012 Annual Forum Nashville, TN September 24, 2012
CURRENT BASELINE WATER QUALITY PROGRAM CONCEPTS Baseline sampling is considered a keystone in our
prevention measures to protect drinking water supplies › Risk management tool to decrease overall risk
Chesapeake has experience in the collection of over 34,000 baseline samples. › Dissolved methane has been detected in 25 percent of all
baseline samples › Significant baseline sampling programs in West Virginia,
Ohio, Pennsylvania, Colorado, Wyoming, and North Dakota › Methane detections have been found in Arkansas, Kansas,
Louisiana, New York, Ohio, Pennsylvania, West Virginia, Colorado, Wyoming, Texas, and North Dakota
› Highest and most widespread concentrations have been found in Louisiana, Pennsylvania, and Ohio 3
CURRENT BASELINE WATER QUALITY PROGRAM CONCEPTS Water Quality Analysis (pre-drill) using independent
environmental consultants (sampling) and analytical laboratories (testing) based on written program documents and procedures › Clarifies expectations for consultants and laboratories
On-going communications between all consultants and laboratories involved in the program › Consistency of sampling procedures › Increased comparability of data between consultants and
laboratories › Field and laboratory auditing conducted by CHK
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CURRENT BASELINE PROGRAM COMPONENTS Regulatory Components
› Variety of Regulatory Programs (following list is not all inclusive, examples only) − Pennsylvania, pre-drill optional but required participation by operator to maintain legal
status. 2500 ft. radius; single pre-drill required.
− West Virginia, one pre-drill required within 1500 ft. with expansion to 2000 ft. if no well found, or when requested by any resident within 1,000 ft.
− Ohio, Senate Bill 315, pre-drill 1500 ft. all areas; 300 ft. of pad in urbanized areas or as requested by director. Single pre-drill required.
− Colorado, specific areas required, pre-drill and post-drill requirements, 2500 ft. sampling radius,
− Texas, special requirements in certain cities e.g. Grand Prairie, Hurst, Lakeside.
− Wyoming – no formal program.
− North Dakota – no formal program.
− Kansas – no formal program.
− Arkansas – no formal program.
− Oklahoma – no formal program.
› Pre-drill sampling is recommended by the MSC
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CURRENT BASELINE PROGRAM COMPONENTS Independent Consultants
› Identify private water sources › Coordinate water sampling survey form delivery
− Critical element in assisting to identify potential sources of variability, e.g. use prior to sampling
› Schedule sampling times with residents/landowners, conduct sampling, and follow-up contact − Photo documentation during sampling – can prove to be a most critical
element − Field notes, site sketch and field activities documentation – specific
timeframes for conversion to electronic form − Verification of multiple contacts and adequate documentation of
refusals for testing − Coordinate delivery of results to landowners & state agencies (where
required) › Assist in Public Outreach Meetings in local community groups
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CURRENT BASELINE PROGRAM COMPONENTS Independent Analytical Laboratories
› Analyze for specific indicator parameters to establish general water quality
› Use scientifically validated methods for testing groundwater and surface water
Data Internally Stored in EQuIS Format › Able to utilize data for statistical reports › Readily access data for complaints or other uses
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WATER TESTING PARAMETERS AND LANDOWNER REPORTS Chesapeake Standard Baseline Parameters
› Field Screening: pH, Temperature, Specific Conductance, DO, Turbidity, Eh, Hydrogen Sulfide, GE/FID/PID and LEL readings,
› General Chemistry: pH, Specific Conductance, Turbidity, Chloride, Sulfate, Bromide, Carbonate Alkalinity, Bicarbonate Alkalinity, MBAS, TDS, and TSS
› Total Metals: Ag, As, Ba, Ca, Cd, Cr, Fe, Hg, Li, K, Mg, Mn, Na, Pb, S, Se, and Sr − Dissolved Metals: Fe and Mn, if field turbidity
exceeds 10 NTU › Organics: BTEX, O&G (HEM), and Dissolved Light Gases
(C1-C3) − Rush dissolved light gas results if field LEL reading is
greater than 10% or sample is effervescent › Isotopic Methane: if dissolved methane exceeds 20
mg/L − Some states have a lower threshold
of 1 to 2 mg/L 8
WATER TESTING PARAMETERS & LANDOWNER REPORTS Chesapeake Resident Package
› Full Copy of Analytical Laboratory Report
− How to Read Your Laboratory Report Fact Sheet
› Frequently Asked Questions (FAQs)
› Methane Fact Sheets (when dissolved methane is detected)
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WATER SOURCES & SAMPLING RADIUS Water Sources utilized for household purposes:
› Bathing › Washing › Drinking › Cooking › Other household uses
Sampling Radius: › One thousand feet (1000’) from well pad (surface hole)
location or state regulatory requirement, whichever is greater › Some areas radius is extended (4,000’) based on location
and available water sources
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BASELINE WATER SAMPLING POINT Sample Collection Point:
› Non-invasive sampling − Dissolved gases should be collected
under water head › Water Line from Water Well or Spring:
− Sample point/spigot at well head or prior to treatment/pressure tank
− Base of pressure tank − Sink tap
› Springs: end of the pipe, outlet, or from cistern/water collection system
› Surface water: mid-depth from center of water source
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BENEFITS OF PRE-DRILL SAMPLING & TESTING Better understanding of general water quality in
immediate area
› Water well records obtained during baseline sampling surveys may be incomplete in counties where records are poorly kept
› Landowner knowledge of water quality is documented in Water Sampling Survey
› Help identify areas of pre-existing poor water quality
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BENEFITS OF PRE-DRILL SAMPLING & TESTING Helps establish a baseline of water quality if a
complaint is made
› Use in addition to a timeline for events prior to the complaint
› Additional data can be gleaned from mud logger data, area data compilations, and evaluation of other possible sources (e.g., legacy wells, etc.)
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BENEFITS OF PRE-DRILL SAMPLING & TESTING Landowners receive a full analytical report
documenting their water quality › Provide educational fact sheets to assist landowners in
understanding their resident package. Many landowners do not know even the depth of their well
Help educate the general public in localized town hall meetings
› Helps to overcome public perceptions
› Presents baseline data findings for the general area
› One-on-one sessions are made available
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SPECIAL WELL STUDY VARIABILITY IN WATER QUALITY DATA
Special year long study of 12 water wells monitored for natural groundwater quality changes.
Observations from data collected
› Water quality data varies naturally and occurs over a range (not a single unique value)
› Single baseline data should be used with care
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SPECIAL WELL STUDY SITE 1
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SPECIAL WELL STUDY SITE 1
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SPECIAL WELL STUDY SITE 1
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SPECIAL WELL STUDY SITE 1
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SPECIAL WELL STUDY SITE 1
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SPECIAL WELL STUDY SITE 1
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SPECIAL WELL STUDY SITE 1
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SPECIAL WELL STUDY SITE 1
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LESSONS LEARNED Operator’s program document must be written
Photo documentation is critical
› Consultants must act as the eyes for the operator at each site being sampled
› Photos of wellhead, sample point and any special or unusual conditions noted
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Document all attempts to provide testing
› Consultant must document all
written and oral contact with well owner to offer water sampling in order to establish due diligence
› All refusals must be clearly documented
LESSONS LEARNED
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LESSONS LEARNED Dissolved methane sampling and analyses require
careful consideration
› Lack of consensus on sampling method for dissolved methane
− Trained sampling crews use the same sample collection procedure so that sampling bias is consistent
− Marcellus Shale Coalition has developed Recommended Practices which provide a sampling method which is a consensus guideline for use in the Marcellus shale
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LESSONS LEARNED Dissolved methane analyses and isotopic methane
analysis are not silver bullets
› Multiple lines of evidence are necessary due to the complexity of the issue − Mud gas data, geological data, area groundwater quality data
› When moving into a new operational area, may need to conduct more isotopic analyses, − Especially if there is little to no
data available for groundwater in the area
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