Large-scale natural-gradient tracer test in sand and gravel, Cape Cod, Massachusetts 3. Hydraulic conductivity variability and calculated macrodispersivities

Technical Report · Wed Jan 01 04:00:00 EST 1992

OSTI ID:6902000

Hess, K M; Wolf, S H; Celia, M A

Hydraulic conductivity (K) variability in a sand and gravel aquifer on Cape Cod, Massachusetts, was measured and subsequently used in stochastic transport theories to estimate macrodispersivities. Nearly 1500 K measurements were obtained by borehole flowmeter tests and permeameter analyses of cores. The geometric mean for the flowmeter tests (0.11 cm/s) is similar to that estimated from other field tests. The mean for the permeameter tests (0.035 cm/s) is significantly lower, possibly because of compaction of the cores. The variance for the flowmeter (0.24) is also greater than that for the permeameter (0.14). Geostatistical analyses applying negative exponential models with and without nuggets reveal similar spatial correlation structures for the two data sets. Estimated correlation scales range from 2.9 to 8 m in the horizontal and from 0.18 to 0.38 m in the vertical. Estimates of asymptotic longitudinal dispersivity (0.35-0.78 m) are similar in magnitude to that observed in the natural gradient tracer test (0.96 m) previously conducted at the site. (Copyright (c) 1992 by the American Geophysical Union.)

• Research Organization: Geological Survey, Marlborough, MA (United States). Water Resources Div.
• OSTI ID: 6902000
• Report Number(s): PB-93-107050/XAB
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540220* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (1990-)
AQUIFERS
ENVIRONMENTAL QUALITY
ENVIRONMENTAL TRANSPORT
GROUND WATER
HYDRAULIC CONDUCTIVITY
HYDROGEN COMPOUNDS
HYDROLOGY
ISOTOPE APPLICATIONS
MASS TRANSFER
MASSACHUSETTS
OXYGEN COMPOUNDS
STOCHASTIC PROCESSES
TRACER TECHNIQUES
WATER
WATER QUALITY