Use of particle tracking to improve numerical model calibration and to analyze ground-water flow and contaminant migration, Massachusetts Military Reservation, western Cape Cod, Massachusetts

Abstract

Maps showing simulated effects of increasing horizontal hydraulic conductivity of moraine sediments on model-calculated water-particle pathlines and water-table configuration near Landfill-1 plume area of contamination, western Cape Cod, Massachusetts.

Intercomparison of submarine groundwater discharge estimates from a sandy unconfined aquifer

“…Data from the remaining wells reveals hydraulic conductivity values ranging from 32 to 150 m d À1 in the surficial aquifer with a geometric mean of 52 m d À1 . These values fall within the expected range for clean sands (Freeze and Cherry, 1979) and are consistent with permeameter measurements of 43-54 m d À1 made using drill cuttings (Michael, 2004) and with values reported for similar lithology elsewhere on the Cape of 45-85 m d À1 (Masterson et al, 1997b). A slug test in the fine-grained material at MIT-45, which is screened 12 m below ground, reveals a two order of magnitude reduction in hydraulic conductivity.…”

Flow and nutrient dynamics in a subterranean estuary (Waquoit Bay, MA, USA): Field data and reactive transport modeling

“…1), also drain at the northern end of the bay. Hydrogeological cross sections along the Waquoit Bay watershed reveal a thinning in the depth of the upper unconfined aquifer at the head of bay to $11 m (Cambareri and Eichner, 1998), where it consists of relatively homogeneous medium to fine sands, bounded by a less permeable layer of fine sand, silt and clay (Masterson et al, 1997). In the upper aquifer, the range of hydraulic conductivity values obtained from slug tests varies between 3.7 Â 10 À4 and 1.7 Â 10 À3 m s À1 , with a geometric mean of 6 Â 10 À4 m s À1 (Mulligan and Charette, 2006).…”

Mineral dissolution in the Cape Cod aquifer, Massachusetts, USA: I . Reaction stoichiometry and impact of accessory feldspar and glauconite on strontium isotopes, solute concentrations, and REY distribution 1 1Associate Editor: L. M. Walter

“…For all flow paths, slight increases in Si concentration were observed. However, hydraulic conductivity in the aquifer ranges over one order of magnitude (LeBlanc et al, 1991) and the horizontal/vertical conductivity ratio varies between 2 and 5 (Masterson et al, 1996) due to lenses and layers of coarse grained sediment. Hence, actual groundwater pathways in the upper part of the Cape Cod aquifer we sampled…”

“…Sediments were deposited as moraines, basal till, and pro-glacial lake deposits. The sediment within the study area is stratified glacial outwash consisting primarily of unconsolidated medium-coarse sand with some gravel and underlain by fine sand and silt (Barber, 1985;Coston et al, 1995;Masterson et al, 1996). Median grain size (by weight) is approximately 0.5 mm, silt-sized and clay-sized particles comprise less than 1 wt.% of the sediment, and sedimentary organic carbon represents Ͻ0.1 wt.% (Barber et al, 1992).…”

“…Such unconsolidated glacial aquifers are widespread and of great importance, because water supplies for many metropolitan areas are derived from such aquifers. In addition, the groundwater flow, the groundwater chemistry, and also the sediment mineralogy at Cape Cod have been thoroughly and extensively investigated (e.g., Barber, 1985;LeBlanc et al, 1991;Barber et al, 1992;Coston et al, 1995;Masterson et al, 1996;DeSimone et al, 1997;Savoie and LeBlanc, 1998;Yau, 1999, Shapiro et al, 1999and references therein). This site represents a relatively simple aquifer -a best case aquifer wherein analysis of mineral dissolution was anticipated to be unequivocal and where the hydrology was well-understood.…”