Site investigation report for Waste Area Grouping 4 at Oak Ridge National Laboratory. Volume 1, Text: Environmental Restoration Program

Abstract

DISCLAIMERThai report was prepared at an account of work sponsored by an agency of the United Sutes Government. Neither the United States Government nor aay agency thereof, nor aay of their employees, makes aay warranty, express or implied, or «amines any legal liability or responsi bility f*r the accnracy. completeness, or uscfnlncss of any infonaation, apparatus, product, or proem disclosed, or represents that its use would nu infringe privately owned rights. Refer ence herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply hs endorsement, recom mendation, or favoring by the United Sutes Government or any agency thereof. The views and opinions of author» expressed herein do not necessarily state or reflect those of the United States Government or aay agency thereof. Prepared for U.S. Department of Energy ACKNOWLEDGMENTSThe characterization project summarized in this report represents the efforts of a team of investigators brought together to conduct an expedited project The project occurred in two discrete stages, both of limited duration. The field season available for conducting the second stage of me work was expected to last only 10 weeks, and tbe goal was to establish instrumentation, install drive-point wells, collect samples, and gather sufficient data to provide a basis for a decision on an interim action to control ,0 Sr releases from Waste Area Grouping 4. The first draft of the report was requested about 2 weeks after most of the field operations ended, although some data collection was sbH in progress. The successful accomplishment of the project objectives is a tribute to the participants and their willingness to work as a team. Because each component of this report was prepared by a subgroup of the team, it was considered important to identify the participants and their areas of responsibilities. They are summarized in the table below. Surface water data indicate mat a sarjstaorM quantity of ^fc being rekased from me burial trenches i» SWSA 4. Tb^ trenches contributed 25% ofme^Sr release observed at White Oak Dam for me period 1987-1994 and aboat 14% of me total ORNLctf-stte risk via the ooalong waterpathway. The site mvestigatfem reported berew?. uadertakea to locate the sources of "Sr release, to detenniae a relative ranking of tlieir importance, and to provide suff^^ to evaluate alternatives for an interim ineas«e to cc«tiol release and Ansredoce me off-sh^risL The strategy involved 'liack-trackúg" along the discharge pathway to me western portion of SWSA 4, which contributes about 80% of the *5r release. In matares, radiation surveys were conducted to locate discrete discharge points, and suspect trenches upslope of the seeps were examined OMoagh use of drive point wefls to qiiantify^r concentrations and pmpointlwai^^ of "hot spots." The investigarte» also siinultanco^ the tributary draining SWSA 4 so that the relative importance of identified sources could be determined. Tracer studies were...