Saturated Zone. The capillary pressure in the saturated zone where up to three phases (water, organic, microemulsion) exist according to the surfactant phase behavior is calculated as follows. Two-phase organic-water The drainage capillary pressure is modeled using the Xxxxxx-Xxxxx function: ⎛⎜ Pb ⎞⎟ λd ⎝ Pc12 ⎠ = Sn1 (2.53) where λd is a measure of pore size distribution of the medium, the entry pressure Pb equals Cpcd the normalized water saturation is defined as Sn1 = S1 − S1 r 1 − S1r and φ k
Saturated Zone. The part of the Unconfined Aquifer below the water table where the soil pores are completely filled with water.
Saturated Zone. The organic phase movement during the spill event in the saturated zone where up to two fluid phases (water and organic) exist is assumed to be in the drainage direction. The organic movement during the remediation process, e.g., water flushing or surfactant injection, however, is assumed to be in the imbibition direction for the entire injection period. Organic spill process The relative permeabilities for water and organic fluid phases are r1 kr1 = ko (Sn 1 )n1 (2.64) r 2 kr 2 = ko (1 − Sn 1 )n2 (2.65) where the normalized water saturation is Sn1 = S1 − S1 r . 1 − S1r Remediation process There are up to three liquid phases present according to the surfactant/water/ organic phase behavior during a SEAR process in the saturated zone. The relative permeabilities are assumed to be unique functions of their respective saturations only. The latter assumption is supported by experimental data measured at The University of Texas at Austin for a mixture of petroleum sulfonate, n-decane, isobutyl alcohol, and water (Xxxxxxx et al., 1987; Xxxxxxx, 1990). The relative permeability is defined by xx krℓ = ko (Snℓ )nℓ for ℓ = 1, 2, or 3 (2.66) where the normalized saturations are defined as 3 Snℓ = Sℓ − Sℓr for ℓ = 1, 2, or 3 (2.67)
Saturated Zone. The USGS recognizes that revisions to groundwater-flow and contaminant-transport models require reasonable hydraulic property estimates acquired through aquifer testing and/or geophysical methods. Futhermore, incorporation of hydraulic head and temperature data (MLMS data) in groundwater-flow and contaminant-transport models will provide a valuable dataset to help explain how key geologic features such as sediment layers and layers of dense basalt affect the flow and direction of groundwater within the ESRP aquifer. The current MLMS dataset extends through wet and dry water years, and will be used to examine episodic events, such as surface-water flow in the Big Lost River, to better quantify groundwater recharge from surface-water sources, a potential mechanism for contaminant mobilization in the unsaturated zone. The USGS continues to collect independently derived hydraulic-property estimates through examination of aquifer test data, MLMS hydraulic head data, and geophysical logging. New techniques are being employed to estimate hydraulic properties of discrete fracture networks using analytical techniques developed by the USGS Branch of Geophysics. The USGS continues to make hydraulic testing and geophysical logging a high priority as new boreholes are drilled at the INL. These hydraulic-property estimates are valuable for model testing and validation.
Saturated Zone. The USGS recognizes that to have confidence in the predictive capability of the groundwater model, it is important to develop reasonable estimates for hydraulic properties. These estimates are based on the analysis of aquifer tests and (or) geophysical data. The USGS is incorporating aquifer test results with geophysical techniques, such as flow-meter logging, neutron measurements, and eventually acoustic televiewer measurements, to improve estimates of hydraulic properties and to better predict the flow and direction of groundwater in the aquifer. These advanced borehole testing techniques were applied to xxxxx USGS 140 and 141 drilled in FY 2014 and to xxxxx USGS 142, TAN 2271, and TAN 2272 completed in 2016. Data collected from these xxxxx will be used to better understand contaminant transport in the aquifer south of the ATR Complex, west of the NRF, and at TAN. The improved estimation techniques will be applied to other xxxxx in the study area and will be used to calibrate a plume-scale groundwater model in the future. During FY 2012, the USGS instrumented two additional MLMS boreholes in USGS 131A and USGS 137A. Hydraulic head and temperature measurements collected from these two xxxxx, along with more data from the other nine MLMS from 2011-13, were summarized in a report published in FY 2015 (Xxxxxxx and Xxxxxx, 2015). During FY 2018, the USGS plans to continue collecting hydraulic head and temperature data from 11 MLMS xxxxx, with measurements collected quarterly at three of the MLMS xxxxx and annually for the rest. A future report is planned to look at 2014-15 data and provide interpretation (Table 3). With record low water levels in the ESRP aquifer in 2016 came the realization that transmissivity estimates for the aquifer published in 1991 (Xxxxxxxx, 1991) were for 10 to 40 feet of aquifer material that is no longer saturated. Additionally, many new monitoring xxxxx have been drilled since the 1991 study. To reassess the transmissivity of the aquifer at the INL, drawdown data was collected in April 2017 from xxxxx sampled for the routine monitoring program. During FY 2018, drawdown in the xxxxx to be sampled in October 2017 will be collected and information will be compiled and interpretated in a report (table 1). As the USGS continues to core boreholes into the ESRP aquifer, attempts will be made to expand our capacity to collect hydraulic properties by exploring new geophysical methods as they become available. Additional data describing the ...
Saturated Zone. The organic phase movement during the spill event in the saturated zone where up to two fluid phases (water and organic) exist is assumed to be in the drainage direction. The organic movement during the remediation process, e.g., water flushing or surfactant injection, however, is assumed to be in the imbibition direction for the entire injection period. Organic spill process The relative permeabilities for water and organic fluid phases are r1 kr1 = ko (Sn 1 )n1 (2.64) r 2 kr 2 = ko
