HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Gee, G. W. Articles by Zachara, J. M. Search for Related Content PubMed Articles by Gee, G. W. Articles by Zachara, J. M. GeoRef GeoRef Citation Agricola Articles by Gee, G. W. Articles by Zachara, J. M. Related Collections Mixed Wastes Radionuclides Vadose Zone Processes and Chemical Transport

SPECIAL SECTION: HANFORD SITE

Hanford Site Vadose Zone Studies: An Overview

Pacific Northwest National Lab., P.O. Box 999, Richland, WA 99352. Pacific Northwest National Laboratory is a multiprogram national laboratory operated for the U.S. Department of Energy by Battelle Memorial Institute under Contract DE-AC0576RLO 1830
^* Corresponding author (glendon.gee{at}pnl.gov).

Received 15 December 2006.

Large quantities of radioactive and chemical wastes resulting from Pu production for nuclear weapons are located in the vadose zone at the USDOE's Hanford Site, north of Richland, WA. The vadose zone here is characterized by often highly stratified glacial-fluvial sediments that give rise to complex subsurface-flow paths that contribute to uncertainty of contaminant fate and transport. Research efforts have focused on answering questions of contaminant transport from the viewpoint of geologic, biologic, geochemical, and hydrologic controls. This special section highlights key research topics concerning vadose zone problems at the Hanford Site. Research indicates that some of the contaminant species (¹³⁷Cs, ⁶⁰Co, ⁹⁰Sr) are retained by Hanford sediments as a result of geochemical reactions, rendering them effectively immobile except under extremely saline or acidic conditions, while other species (⁹⁹Tc, ¹²⁹I, ³H) are typically mobile and have moved deep into the vadose zone and subsequently into groundwater. In addition, large quantities of organics, including carbon tetrachloride, have moved in complex ways as both vapor and liquid in the subsurface. Observed transport of mobile species is linked to liquid discharges and to elevated recharge rates that occur primarily at waste sites where land surfaces are void of vegetation and where winter rains have subsequently penetrated the subsurface wastes. A series of papers in this issue documents progress to date in understanding transport rates at Hanford, why anisotropy strongly affects the distribution of subsurface contaminants, why organic contaminants are difficult to find in the deep vadose zone, and what the impacts of hypersaline fluids are on waste form degradation and subsequent transport.

Abbreviations: CT, carbon tetrachloride • DNAPL, dense nonaqueous phase liquid • SVE, soil vapor extraction

This article has been cited by other articles:

				M. A. Mayes, G. Tang, P. M. Jardine, L. D. McKay, X. L. Yin, M. N. Pace, J. C. Parker, F. Zhang, T. L. Mehlhorn, and R. Dansby-Sparks Influence of Sedimentary Bedding on Reactive Transport Parameters under Unsaturated Conditions Soil Sci. Soc. Am. J., October 21, 2009; 73(6): 1938 - 1946. [Abstract] [Full Text] [PDF]

				R. Dann, M. Close, M. Flintoft, R. Hector, H. Barlow, S. Thomas, and G. Francis Characterization and Estimation of Hydraulic Properties in an Alluvial Gravel Vadose Zone Vadose Zone J., August 11, 2009; 8(3): 651 - 663. [Abstract] [Full Text] [PDF]