Phase II Hydrogeologic Characterization for Mamm Creek
The Phase II Hydrogeologic Characterization for the Mamm Creek Field Area is a continuation of the Phase I study for the same area (URS, 2006), which is located south of the Colorado River between the cities of Rifle and Silt, Colorado. The Phase II study included two field sampling tasks. In Task 1, water quality and gas composition and methane stable isotope samples were collected from domestic wells in the Mamm Creek study area that had previously had one or more compounds of concern at or above regulated concentrations, or that had sodium chloride (Na-Cl) concentrations that suggested possible mixing with Na-Cl water with marine or brackish water characteristics. In Task 2, produced water and natural gas samples were collected from gas wells in the immediate vicinity of domestic wells whose water and gas chemistry sampling results suggested possible potential impacts from deeper formations or other external sources, whether natural or due to natural gas drilling and/or production activities. Phase II of this study was conducted by S.S. Papadopulos & Associates and the final report was published in September 2008. The companion report to the Phase II Study is this Review of Phase II Hydrogeologic Study, interpretations and conclusions prepared by Dr. Geoffrey Thyne, of the University of Wyoming.
Master Document: (all links below are downloadable pdf files)
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Tables
Appendices
Figures
(all links are downloadable pdf files)
Figure 1.1 Location of the Piceance Basin
Figure 1.2 Area of Investigation
Figure 2.1 Simplified Stratigraphy
Figure 4.1 Location of Domestic Water Supply Samples
Figure 4.2 Natural Gas Well Samples
Figure 4.3 Nitrate Concentration Distribution in Domestic Wells
Figure 4.4 Fluoride Concentration Distribution in Domestic Wells
Figure 4.5 Selenium Concentration Distribution in Domestic Wells
Figure 4.6 Sulfate Concentration Distribution in Domestic Wells
Figure 4.7 Chloride Concentration Distribution in Domestic Wells
Figure 4.8 Total Dissolved Solids Concentration Distribution in Domestic Wells
Figure 4.9 Dissolved Methane Concentration Distribution in Domestic Wells
Figure 4.10 Piper Diagram Task 1 Domestic Well Samples by TDS
Figure 4.11 Piper Diagram Task 1 Domestic Well Samples by Depth
Figure 4.12 NA/(Ca+Mg) Ratios for Domestic Well Samples
Figure 4.13 SO4/HCO3 Ratios for Domestic Well Samples
Figure 4.14 Distribution of Water Types
Figure 4.15 Piper Diagram Natural Gas Well Produced Water Samples by TDS
Figure 4.16 Chloride/Bromide Chloride/Boron Ratios vs Chloride Concentrations
Figure 4.17 Chloride/Strontium Calcium/Strontium Ratios vs Chloride Concentrations
Figure 4.18 Sulfate vs Chloride Sulfate/Chloride Ratios vs Chloride Concentrations
Figure 4.19 Carbon & Hydrogen Isotopes of Methane
Figure 4.20 Comparative Molecular & Isotopic Compositions of Biogenic & Thermogenic Gas
Figure 4.21 Domestic & Monitoring Wells with Probable Biogenic & Thermogenic Methane
Figure 4.22 Piper Diagram Comparing Primary Water Samples with QA/QC Results