Estimating nonaqueous phase liquid spatial variability using

0,91

MB

partitioning tracer higher temporal moments

19

stron

6497

ID

College of Engineering, University of Florida

2003

rok

The use of interwell partitioning tracers to quantify the amount of nonaqueous phase liquid (NAPL)

in porous media has been demonstrated in several laboratory and field tests. The primary emphasis

of work to date has been on the use of first temporal moments of tracer breakthrough curve (BTC)

data to estimate the average NAPL saturation. Here we extend the data analysis to the use of

tracer BTC second and third temporal moments to estimate the statistical parameters characterizing

the NAPL spatial distribution. In particular, we examine the fraction f of the streamlines that

contain NAPL and the mean and standard deviation of the distribution of streamline

trajectoryaverage NAPL saturations. Two models are presented based on discretizing tracer swept

volumes into contaminated and uncontaminated zones. The models are applied to data from three-

dimensional numerical simulations, two-dimensional flow laboratory experiments, and field tests at

two sites (Hill Air Force Base, Utah, and a dry cleaner in Jacksonville, Florida). For all cases

considered here, good agreement was found between expected (measured) and estimated values of

f, the fraction of the tracer swept zone that contained NAPL. The effects of nonlinear and

nonequilibrium partitioning as well as correlations between NAPL saturation and saturated hydraulic

conductivity are also considered. INDEX TERMS: 1829 Hydrology: Groundwater hydrology; 1831

Hydrology: Groundwater quality; 1832 Hydrology: Groundwater transport; KEYWORDS:

groundwater hydrology, groundwater quality, groundwater transport Estimating nonaqueous phase

liquid spatial variability using partitioning tracer higher temporal moments