Table 3.

Maximum temperature limits for bacterial survival in compacted Wyoming bentonite in experiments of different durations.

Temperature limit	Duration	Details	Reference
80–130°C	2–3 weeks	Survival of bacteria dramatically reduced after incubation at 80°C at a dry density of 1600 kg m−3 but not 1800 kg m−3. At the higher dry density, some anaerobes could be cultured after two weeks at 121°C and a further week at 130°C. This was suggested to be due to survival as spores.	Stroes-Gascoyne and Hamon (2010)
80°C	Between 2 and 28 weeks	A selection of aerobic and anaerobic bacteria was tested. Bacillus spp. survived up to two weeks but no species survived 28 weeks (including spore-forming sulphate reducers).	(Pedersen et al. 2000a)
Between 50 and 70°C	15 months	A selection of aerobic and anaerobic bacteria was tested. Only spore-forming Desulfotomaculum nigrificans and B. subtilis survived at 70°C.	(Pedersen et al. 2000b)
Between 55 and 67°C	5 years	No aerobic bacteria were culturable from bentonite incubated at or above 67°C.	Fru and Athar (2008)