Results and interpretation of groundwater data obtained from multiport-instrumented coreholes (GW-131 through GS-135), fiscal years 1990 and 1991

Abstract

Frequency distribution of charge balance results for ali unf'tltered analyses...

Report on the remedial investigation of Bear Creek Valley at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 2: Appendix A -- Waste sites, source terms, and waste inventory report; Appendix B -- Description of the field activities and report database; Appendix C -- Characterization of hydrogeologic setting report

“…Although there are no clearly defined abrupt hydrogeologic changes in the elastic formations with depth, a general hydrogeologic stratigraphy can be defined that separates these formations into shallow-, intermediate-, and deep-flow regimes (Fig C.8; Solomon et al 1992). The boundary between shallow and intermediate intervals is defined by a consistent change in groundwater geochemistry and -30m(100 fi) depth that indicates flow is considerably slower below this depth (Haase 1991;Dreier et al 1993). The boundary between intermediate and deep intervals is poorly defined and is indicated by a change in groundwater geochemistry that has been observed between -100 and 150 m (328 and 492 ft) depth (Solomon 1992;Haase 1991;Dreier et al 1993).…”

“…The boundary between shallow and intermediate intervals is defined by a consistent change in groundwater geochemistry and -30m(100 fi) depth that indicates flow is considerably slower below this depth (Haase 1991;Dreier et al 1993). The boundary between intermediate and deep intervals is poorly defined and is indicated by a change in groundwater geochemistry that has been observed between -100 and 150 m (328 and 492 ft) depth (Solomon 1992;Haase 1991;Dreier et al 1993). The deep interval probably relates to the base of effective flow in the elastic formations.…”

“…This divide is the eastern boundary of the Bear Creek I-Iydrogeologic Regime (BCHR). Dreier et al (1993) present detailed hydraulic head measurements from four deep coreholes , the locations of which forma transect across BCV in the vicinity of the S-3 Site. WestbayTM multiport samplers installed in each of the coreholes allowed hydraulic head measurements, hydraulic testing, and water sampling in discrete intervals within the groundwater system.…”

“…Haase (1991) reportedthree distinct groundwater geochemical facies in BCV and concluded that the major ion geochemis~of groundwater in BCV is a function of residence time and flow path length. Dreier et al (1993) identify these facies in the deep multiport well transect of BCV and an additional facies (Figs. C. 15 and C.1 6).…”

“…Ongoing work is summarized each year in the Groundwater Quality Report (GWQR) (e.g., HSW 1995). These studies include quarterly water level measurements summarized in the annual GWQ~data from R1.sconducted in BCV during 1994 and 1995 (Appendix B), data from numerous previous studies carried out in BCV between 1984(e.g., Golder and Associates 1988aGeraghty and Miller 1986), the Exit Pathway Monitoring Program (Shevenell et al 1992), and other more specific studies carried out by the Environmental Sciences Division at Oak Ridge National Laboratory for the Groundwater Protection Program (GWPP) or the ORR Hydrology and Geology Studies (ORRHAGS) program (e.g., Dreier et al 1993;GoldStrand 1995;Moline and Schreiber 1995, draft). Using these da@ the resulting conceptual model builds on the previous theories and hypotheses for groundwater movement on the ORR (e.g., Solomon et al 1992;Moore and Toran 1992).…”