Krasnodar GRES Project Volume I11 Environmental Assessment

confined to Chugushsky and Voznesensky fractures, where a number of
earthquakes of class 6-7 were recorded over the period of observation (November
1983 - March 1984) at minimum distances of 15-20 km from the "Gubskaya"
site.
These studies show that Mid-Labinsky fracture is a deformation of the 3rd order
and is limited by the active Chugushsky deformation, and within this block,
where the site is located, it does not extend, Seismic hazard stemming from this
fracture is considerably lower (approximately by 1 point) than that of the more
active zones listed above.
The main power plant structures on the Krasnodar GRES site are situated on a
pebble base with a low (20-25%) content of sandy filler. In terms of their
characteristics these grounds pertain to the 2-nd grade and consequently the
seismic effect of the defined WHO zones within the Krasnodar GRES site will not
exceed 8 points for dry and flooded grounds.
A sketch of the seismic zones in the Krasnodar GRES region is presented in
Supplement 17.
4.3.1.3 Topography
The Krasnodar GRES site is located on the piedmonts of the North Caucasus in the
south-west of the Krasnodar region in the Laba river valley (left tributary of the
Kuban river) 5 km to the south of Mostovskoy (regional center).
Bus routes connect this region with the city of Maikop (50 km) and the territorial
center Krasnodar (I80 km). A railway branch Labinsk-Shedok runs at a distance of
several kilometers from the Krasnodar GRES site.
Settlements Mostovskoy, Shedok, Perepravnaya, Zassovskaya and Kaladzhinskaya
are large populated areas in this region.
The main water artery of the region is Laba river 1.6 m deep and up to 70 wide.
Upstream of the site the river is branched (Malaya and Bolshaya rivers), and
downstream on the left the tributary Khodz flows into it. The feeding rivers are
mixed, the surface runoff is formed primarily by the thawing of snow and glaciers
in the northern slope of the Main Caucasian Range. Spring-summer floods and
high water during the year are typical of the Laba river. The Laba and Khodz rivers
pertail? to fish breeding water bodies of the I-st and 2-nd grade.
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