Post on 23-Feb-2016
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Water Quality and Hydraulic Fracturing: GIS AnalysisKyra Reumann-MooreREU in Environmental SustainabilityMentor: Joe RyanGraduate Student: Jessica Dehart
Background on Hydraulic Fracturing
•Concern over spills, faulty casing, flawed cementing, or travel through faults
•Evidence of elevated methane within 1 km of producing wells in PA
•Pavillion, WY study: elevated pH, BTEX, Cl–,K+
•COGA Voluntary Baseline Sampling Program•COGCC mandatory groundwater monitoring
▫Only state to require samples after drilling▫One of three to require sampling at all
AirWaterGas SRN• 5 year NSF grant of $12
million • Awarded Fall 2012• CU-Boulder is the lead
institution• My area: Water Quality
▫ Will fracturing fluid contaminate drinking water aquifers?
▫ Focus on the Denver- Julesburg basin
▫ Look at: contamination levels, parameter correlations, oil and gas wells proximity
COGCC Database•Individual water well sample sites•Oil and gas wells shapefile•Looked at parameters based on EPA and
CDPHE drinking water quality standards•627 samples used in analysis•Problems: lack of coordinates, qualifier
codes in data, parameters not reported consistently
COGCC DatabaseThe online database map A typical sample site
page
Wells in the DJ BasinOil and Gas Wells in the DJ Basin
Water Wells in the DJ Basin
As reported by the COGCC
Field Sampling• With Stephen Osborn and
a team from Cal Poly Pomona
• 39 sample sites in Boulder, Adams, and Weld counties
• Helped Jessica Dehart take 6 samples at each site for DOC, VOCs, and pesticide analysis
• Field data: latitude and longitude, pH, specific conductivity
• Also sampled for future analysis: dissolved gases, isotopes, alkalinity, metals
Water Quality Parameters
Spatial Trends
Methane and TDS concentrations
Field Data Locations
Field and COGCC Conductivity
Methane Concentrations Near WellsMy graph based on COGCC data Osborn’s graph from PA
*Please note the difference in scale*
Carbon isotopesMy graph based on COGCC data Osborn’s graph from PA
Delta 13C C1 (per mil)
Met
hane
(mg/
L)
Other Concentrations Near Wells
Water Quality Comparisons
Number of Wells Nearby & Well Depth
Areas for Further Research•What geologic formations the water wells
are in•Further study of carbon isotopes •Fault proximity•Time between oil and gas well activity
and water well sampling•More field sampling, especially at COGCC
sites with high concentrations
Acknowledgments• SRN – Air Water Gas Research Group
▫ Dr. Joe Ryan▫ Jessica Dehart▫ Dr. Stephen Osborn
• National Science Foundation• Dr. Lupita Montoya• COGCC• TestAmerica, Accutest, ALS Environmental