Utilizing Temperature and Brine Inflow Measurements to Constrain Reservoir Parameters During a Salt Heater Test

Richard S Jayne,Kristopher L Kuhlman

doi:10.3390/min10111025

Abstract

Brine availability in salt has multiple implications for the safety and design of a nuclear waste storage facility. Brine availability includes both the distribution and transport of brine through a damaged zone around boreholes or drifts excavated into the salt. Coupled thermal, hydrological, mechanical, and chemical processes taking place within heated bedded salt are complex; as part of DECOVALEX 2023 Task E this study takes a parsimonious modeling approach utilizing analytical and numerical one-dimensional simulations to match field measurements of temperature and brine inflow around a heater. The one-dimensional modeling results presented arrive at best-fit thermal conductivity of intact salt, and the permeability and porosity of damaged salt of 5.74 W/m·K, 10−17 m2, and ≈ 0.02, respectively.

Highlights

IntroductionSeveral underground field studies have investigated the feasibility of nuclear waste disposal within salt formations across the United States, Project Salt Vault [2], Avery Island [3,4,5], the Deaf Smith site [6,7], and most recently the Waste Isolation Pilot Plant (WIPP) (e.g., [8,9,10,11,12,13,14]), which is currently an active research and disposal (non-heat generating transuranic defense waste) facility
The best-fit thermal parameters are used within a 1D cylindrically symmetric TH TOUGH2 [39] model to solve for both heat and mass transport to match data collected at the Brine Availability Test in Salt (BATS) site in order to constrain the hydrologic parameters of the DRZ that control brine inflow
The safety of nuclear waste disposal within bedded salt is contingent on the long-term isolation capabilities of the salt formation as a whole

Summary

Introduction

Several underground field studies have investigated the feasibility of nuclear waste disposal within salt formations across the United States, Project Salt Vault [2], Avery Island [3,4,5], the Deaf Smith site [6,7], and most recently the Waste Isolation Pilot Plant (WIPP) (e.g., [8,9,10,11,12,13,14]), which is currently an active research and disposal (non-heat generating transuranic defense waste) facility What makes salt such an interesting and potentially effective disposal medium is its low permeability [15]. While undisturbed rock salt has almost immeasurably low porosity and permeability, upon excavation, a damaged region develops surrounding the excavation [18]

Methods

Results

Conclusion