Some of the illustrative concepts for the disposal of intermediate-level waste in a geological disposal facility in the UK employ a cementitious backfill around the waste packages. The concept for higher strength rocks would use a highly alkaline backfill composed of Portland cement (now known as CEM I), hydrated lime and limestone flour, referred to as Nirex reference vault backfill (NRVB).

This paper reports a study of the extensive leaching of cured NRVB in a range of generic leachant compositions (deionized water, 0.1 M and 1 M NaCl solutions) under flow-through conditions using a flexible wall permeameter. The experiments were designed to run for up to two years and to pass at least 1000 volumes of leachant (defined as the cumulative leachate volume produced/NRVB solid specimen volume) through the NRVB samples. Results for the pH evolution profiles of the leachates and the microstructural analysis of the unleached and leached samples are presented.

It is not possible for persons within and between the many disciplines involved in disasters to communicate with each other without clear definitions of the specific terms that are used. In many instances, the same terms have different meanings in different disciplines. Thus, a standardized set of definitions is provided in this chapter and in the associated Glossary of Terms. Some definitions discussed in this Chapter include: (1) disaster; (2) medical disaster; (3) hazard; (4) risk; (5) prevention; (6) modification; (7) event (including onset, duration, amplitude, intensity, scale, and magnitude); (8) impact; (9) mitigation; (10) preparedness; (11) damage; (12) vulnerability; (13) resilience; (14) absorbing capacity; (15) buffering capacity; (16) disaster management; (17) response; and (18) recovery. An annotated, comprehensive set of definitions is provided in the Glossary of Terms in these Guidelines.