UNCONTROLLED When Printed UNCONTROLLED When Printed Nevada DOE/NV--659 Environmental Restoration Project Corrective Action Investigation Plan for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nevada Controlled Copy No.: Revision No.: 0 September 2000 Approved for public release; further dissemination unlimited. Environmental Restoration Division U.S. Department of Energy UNCONTROLLED When Printed Nevada Operations Office Available for sale to the public, in paper, from: U.S. Department of Commerce National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 Phone: 800.553.6847 Fax: 703.605.6900 Email: [email protected] Online ordering: http//www.ntis.gov/ordering.htm Available electronically at http://www.doe.gov/bridge. Available for a processing fee to U.S. Department of Energy and its contractors, in paper, from: U.S. Department of Energy Office of Scientific and Technical Information P.O. Box 62 Oak Ridge, TN 37831-0062 Phone: 865.576.8401 Fax: 865.576.5728 Email: [email protected] Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof or its contractors or subcontractors. Printed on recycled paper UNCONTROLLED When Printed DOE/NV--659 CORRECTIVE ACTION INVESTIGATION PLAN FOR CORRECTIVE ACTION UNIT 97: YUCCA FLAT/CLIMAX MINE NEVADA TEST SITE, NEVADA DOE Nevada Operations Office Las Vegas, Nevada Controlled Copy No.: Revision No.: 0 September 2000 Approved for public release; further dissemination unlimited. UNCONTROLLED When Printed CORRECTIVE ACTION INVESTIGATION PLAN FOR CORRECTIVE ACTION UNIT 97: YUCCA FLAT/CLIMAX MINE NEVADA TEST SITE, NEVADA Approved by: Date: Robert M. Bangerter, Project Manager Underground Test Area Project Approved by: Date: Runore C. Wycoff, Division Director Environmental Restoration Division UNCONTROLLED When Printed CAU 97 CAIP Section: Contents Revision: 0 Date: 09/29/2000 Page i of xx Table of Contents List of Figures. vii List of Plates. .x List of Tables. xi List of Acronyms and Abbreviations . xiv List of Stratigraphic Unit Symbols. .xx 1.0 Introduction. 1 1.1 Purpose . 3 1.2 Scope. 4 1.3 Summary of the CAIP. 5 1.3.1 Overview of Technical Elements of CAIP. 5 1.3.1.1 Characterization Activities . 8 1.3.1.2 Assessment of CAU-Related Data . 8 1.3.1.3 Development of Numerical Groundwater Flow and Transport Model . 9 1.3.1.4 Verification of Numerical Groundwater Flow and Contaminant Transport Model . 9 1.3.1.5 Prediction of Contaminant Boundary . 10 1.3.1.6 CAI Documentation . 10 1.3.2 Document Organization . 10 2.0 Legal/Regulatory Requirements. 12 2.1 Federal Facility Agreement and Consent Order. 12 2.1.1 FFACO Requirements . 12 2.1.1.1 General Requirements . 12 2.1.1.2 Specific Requirements . 13 2.1.2 Corrective Action Strategy. 15 2.1.2.1 Description of Corrective Action Strategy . 15 2.1.2.1.1General Definition of Contaminant Boundary . 15 2.1.2.1.2Process Description . 16 2.1.2.2 Implementation of Corrective Action Strategy . 19 2.1.2.2.1Specific Definition of the Contaminant Boundary . 20 2.1.2.2.2Corrective Action Investigation . 20 2.1.2.2.3Corrective Action Implementation and CAU Closure . 24 3.0 Description of Corrective Action Units. 25 3.1 Investigative Background. 25 9/28/00 P:\Doc-prod\097_Yucca Flat\097_YF&CM_CAIP\Rev_0\MaindocTOC.fm UNCONTROLLED When Printed CAU 97 CAIP Section: Contents Revision: 0 Date: 09/29/2000 Page ii of xx Table of Contents (Continued) 3.2 Operational History. 34 3.2.1 General . 34 3.2.2 Underground Nuclear Testing in the Yucca Flat/Climax Mine Area. 35 3.3 Corrective Action Sites. 39 3.4 Physical Setting. 39 3.4.1 Climate . 63 3.4.2 Topography. 66 3.4.3 Surface Water . 67 3.4.4 Geology . 68 3.4.4.1 Regional Geology . 68 3.4.4.2 Geology of Yucca Flat and Vicinity . 72 3.4.5 Hydrogeology . 83 3.4.5.1 Regional Hydrogeology . 83 3.4.5.1.1 Hydrostratigraphy . 83 3.4.5.1.2 Groundwater . 87 3.4.5.2 Hydrogeology of the Investigation Area . 91 3.4.5.2.1 Hydrostratigraphy . 91 3.4.5.2.2 Groundwater Hydrology . 98 3.4.6 Groundwater Chemistry . 106 3.4.6.1 General Groundwater Chemistry . 108 3.4.6.1.1 Regional Groundwater Chemistry . 108 3.4.6.1.2 Groundwater Chemistry of the Investigation Area . 110 3.4.6.2 Isotope Chemistry . 116 3.4.6.2.1 Hydrogen and Oxygen . 116 3.4.6.2.2 Carbon Isotopes . 119 3.4.7 Groundwater Radiochemistry. 122 3.4.7.1 Hydrologic Resources Management Program . 123 3.4.7.1.1 NASH (U-2ce) . 123 3.4.7.1.2 BILBY (U-3cn) . 125 3.4.7.1.3 BOURBON (U-7n) . 127 3.4.7.1.4 DALHART (U-4u) . 127 3.4.7.1.5 GASCON (U-4t) . 130 3.4.7.1.6 ALEMAN (U-3kz)/SANDREEF (U-7aq) . 131 3.4.7.1.7 AGILE (U-2v)/COMMODORE (U-2am) . 133 3.4.7.1.8 BASEBALL (U-7ba) . 135 3.4.7.1.9 INGOT (U-2gg) . 135 3.4.7.1.10 PILEDRIVER (U-15.01) . 136 3.4.7.1.11 Summary of the HRMP Data . 137 3.4.7.2 Long-Term Hydrological Monitoring Program . 137 3.4.7.3 DOE/NV Annual Environmental Monitoring . 139 UNCONTROLLED When Printed CAU 97 CAIP Section: Contents Revision: 0 Date: 09/29/2000 Page iii of xx Table of Contents (Continued) 3.4.7.4 DOE/NV Environmental Restoration Program . 145 3.4.7.5 Tritium Variations In Yucca Flat Groundwater . 145 3.4.8 Transport Parameters . 147 3.4.8.1 Porosity . 149 3.4.8.2 Dispersion . 152 3.4.8.3 Matrix Diffusion Coefficient . 154 3.4.8.4 Distribution Coefficients . 155 3.4.8.5 Colloidal Transport . 157 3.5 Contaminants . 159 3.5.1 Radioactive and Hazardous Substances Present. 159 3.5.2 Potential Contaminants for the CAI . 161 3.6 Conceptual Model of the CAU . 164 3.6.1 Release and Discharge Mechanisms . 165 3.6.1.1 Release Mechanisms . 165 3.6.1.2 Discharge Mechanisms . 170 3.6.2 Migration Routes . 171 3.6.2.1 Groundwater Flow Paths . 171 3.6.2.2 Contaminant Concentrations and Travel Times . 174 3.6.3 Contaminated Media . 177 3.6.4 Exposure Pathways. 178 3.6.5 Uncertainties. 178 3.7 Preliminary Corrective Action Levels . ..