Microbiologic processes in Oligocene deposits around subway tunnels following completion of caisson work
Kozlova, I.A.; Andreiuk, E.I.; Tsokur, N.I.; Antonovskaia, N.S.
Mikrobiolohichnyi Zhurnal 38(5): 563-570
1976
ISSN/ISBN: 0201-8462 PMID: 1012075 Document Number: 98948
The microbiological process was studied in the Oligocene deposits around subway tunnels [Kiev, Ukrainian SSR, USSR] after completion of the caisson works. The studies were performed in places where appearance of the aggressive acid medium was observed. The 4 yr observations showed that a decrease in ground aeration around the tunnels, associated with cessation of the caisson passage, caused a drop in the amount and oxidative activity of Thiobacillus ferrooxidans and T. thiooxidans. This fact resulted in changing the medium around the tunnels from acid to neutral. The correlation between the amount of acidophilic thionic bacteria and pH of the medium suggests that these bacteria are the main biological factor determining the ecological environment in man-made tunnels. This fact taken into account when choosing the method of tunneling.