Busted Butte Unsaturated Zone Transport Test: Fiscal Year 1998 Status Report Yucca Mountain Site Characterization Program Deliverable SPU85M4

摘要

This report describes the status of the Busted Butte Unsaturated Zone Transport Test (UZTT) and documents the progress of construction activities and site and laboratory characterization activities undertaken in fiscal year 1998. Also presented are predictive flow-and-transport simulations for Test Phases 1 and 2 of testing and the preliminary results and status of these test phases. Future anticipated results obtained from unsaturated-zone (UZ) transport testing in the Calico Hills Formation at Busted Butte are also discussedin view of their importance to performance assessment (PA) needs to build confidence in and reduce the uncertainty of site-scale flow-and-transport models and their abstractions for performance for license application. The principal objectives of the test are to addressuncertainties associated with flow and transport in the UZ site-process models for Yucca Mountain, as identified by the PA working group in February 1997. These include but are not restricted to: (1) The effect of heterogeneities on flow and transport in unsaturated and partially saturated conditions in the Calico Hills Formation. In particular, the test aims to address issues relevant to fracture-matrix interactions andpermeability contrast boundaries; (2) The migration behavior of colloidsin fractured and unfractured Calico Hills rocks; (3) The validation through field testing of laboratory sorption experiments in unsaturated Calico Hills rocks; (4) The evaluation of the 3-D site-scale flow-and-transport process model (i.e., equivalent-continuum/ dual-permeability/ discrete-fracture-fault representations of flow and transport) used in the PA abstractions for license application; and (5) The effect of scaling from lab scale to field scale and site scale.