Krasnodar GRES Project Volume I11 Environmental Assessment

4.3.1.10 Geological Processes and Anomalies
The Krasnodar GRES site has a dip towards north-east at an angle 4-7 degrees.
The site is composed of thick (10-20 m) alluvium, occurring on clays of Maikopian
series.
The right bank of the Laba river shows distinct slide masses of ground 10-45 m
thick, containing clay with detritus of bed rock. The development of land sliding
phenomena arises from water erosion of the Laba river slope. The most intense
destructive processes took place in the upper quaternary period. At a later period,
the erosion processes gradually abated due to a retreat of the river from the bank.
At present, landslides are stabilized, being in a steady state.
On the left bank of the Laba (where the Krasnodar GRES construction site is
located) no landslide phenomena have been observed.
Anomalous phenomena include the following:
- Hail. The number of days with hailstorms varies from 2 to 8, and the
duration - from several minutes to a quarter of an hour, predominantly in
the afternoon and evening hours. In 1971, in the Labinsk and Mostovskoy
region there were storms with hail having a diameter of 50 mm. A hail
control station is operative in the Labinsk region (Vesyolyi).
- Ice covering. The duration of ice covering processes may span 7-1 2 days.
- Dust storms. They were recorded in 1967 and 1969. The visibility in this
case dropped to 200-500 m. The probability of storms in this region is once
every 50 years. Strong winds in the region of the Krasnodar GRES are rare,
but in squalls wind velocity can reach over 25 m/s, resulting in fallen trees
and posts.
- In the Krasnodar region (near Starominskaya settlement) there was a
hurricane on land, which lasted 20 min. The wind velocity in this case
reached 300 m/s. The probability of such hurricane in the Krasnodar GRES
region is only 1 %.
4.3.1 . I 1 Soil Types
The main area within agricultural farms is composed of chernozems (See Figure
4-1). Leached and leached compressed chernozems account for 25% of the total
studied soils, and compact chernozem for 5%.
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