Data Qualification Report: Precipitation Chloride Data for Use on the Yucca Mountain Project

Abstract

The data covered by this qualification report have been cited in analysis/model reports (AMRs) to support the Site Recommendation in determining the suitability of Yucca Mountain as a repository for high level nuclear waste. Those analyses cited both qualified and unqualified hydrochemical data. This report evaluates unqualified precipitation chloride data based on the pedigree of the data and within the context of supporting analyses on the Yucca Mountain Project (YMP). The following AMRs use the unqualified chloride data considered in this report: (1) AMR S0040, ''Geochemical and Isotopic Constraints on Groundwater Flow Directions, Mixing and Recharge at Yucca Mountain'' (ANL-NBS-HS-000021) (Kwicklis 2000)--an analysis of groundwater recharge rates, flow directions and velocities, and mixing proportions of water from different source areas based on groundwater geochemical and isotopic data. (2) AMR U0085, ''Analysis of Geochemical Data for the Unsaturated Zone'' (ANL-NBS-HS-000017) (Fabryka-Martin 2000)--identifies fluid geochemical parameters for the unsaturated zone, local precipitation, and surface water; discusses the occurrence and origins of fracture minerals; and presents a thermal history of the unsaturated zone. These data are being evaluated for inclusion in technical products to include AMRs and Process Modeling Reports (PMRs) that support the Site Recommendation and that may also be used to support the License Application. A finding that the precipitation chloride data are qualified means that the data are adequate for generalized use and can be appropriately used in a wide variety of applications, so long as consideration is given to limitations on the accuracy, precision and representativeness of the data for an intended use in a technical product.