Developed in the 1970s in Sweden for thermal and hydrological responses in hard rock to emplacements of spent nuclear materials, underground research laboratories (Ur's) have since been and are continuously being established worldwide in different formations for studying coupled thermal-hydrological-mechanical-chemical biological processes, as well as for CO2 sequestration testing. Deep underground laboratories have been concurrently developed for physics research from the middle of the 20th century to the present. The knowledge and experience from Ur's at different sites locally, nationally, and regionally can certainly be networked globally. In this article, we evaluate the status of Ur's in preparation for a URL network workshop associated with the 2011 ISM Beijing Congress. The relatively quiet conditions underground and the optimum signal-to-noise ratios are among factors favoring linkages among Ur's for interdisciplinary studies and for developing global networks. International and interdisciplinary collaborations enhance interest in formulating URL networks and in demonstrating underground locations as potential settings for technological innovations.
An Underground Research Laboratory (URL) workshop is proposed for October 17, 2011, one day before the technical program of the International Society for Rock Mechanics (ISM) 2011 Beijing Congress. The URL workshop concept and logistics were discussed with ISM directors and colleagues, and the URL Workshop scheme was recently presented to the American Rock Mechanics Association (ARMS). We plan to schedule the one-day workshop with overview lectures, covering different topics given by experts. In the following sections, case histories from underground investigations in past decades are first summarized, to form the basis for addressing key questions and mechanisms in the formation of URL global networks. Thus, the URL workshop plans to cover primarily:
Ur's for nuclear waste research, with over six sites existing in Europe, three in North America, four in Japan, one in Korea, and one planned in China;
deep underground laboratories (Du's) dedicated primarily to basic physics research, with ~10 sites operated or planned worldwide; and
mines and underground facilities for energy and environmental research, such as CO2 capture and storage study networks in Europe and North America, and the biology-seismic study site in South Africa.
Topics 2–6 are on broad issues, 7–11 on detailed findings, leading to network discussions in 12.
The Strips Sweden iron mine was converted in 1977 to a hard rock URL—the first hard rock URL dedicated to thermal mechanical testing and hydrological flow/transport characterization [2–4]. The thermal-mechanical studies there used heaters emplace below drift floors to simulate full-scale and scaled-down spent-nuclear-fuel canisters. Fracture deformations in the granitic rock (and crystalline rocks in general) were likely the main reason for the lower induced stress and the lesser deformations measured in the field than predicted by elastic models, which used intact rock properties that were derived from laboratory tests.