Caspian Sea: State of the Environment 2019

Data from the monitoring carried out by Ro- shydromet as part of a special extended pro- gramme at more than 100 stations were used to assess pollution and seawater quality in the northern and north-western part of the Caspian

ately polluted”. In the Karazhanbas area, and along the Kenderli–Divichi, Peschanniy–Derbent and Mangyshlak–Chechen cross sections, seawater quality was assessed as “clean” (Monakhov 2014a; Monakhov 2014b; Monakhov 2015).

Table 5.8: Main chemical composition and marine pollution indicators in areas close to oilfields

Concentration in 2017

Background concentration

Indicator

Horizon

Contemporary **

Historical *

Filanovsky Field

Korchagin Field

7.33…11.84 7.28…11.96 1.43…3.84 1.26…3.85 7.98…8.44 7.99…8.45 12.2…86.2 10.6…84.4 359…714 369…769 1.07…2.70 1.12…2.80 18.5…39.9 19.6…39.7 376…1060 397…1025 0.04…0.13 0.01…0.13 0.018…0.094 0.018…0.095

7.5…11.9 7.4…12.0 1.02…2.17 1.08…2.08 8.23…8.42 8.20…8.40 0.6…39.1 0.5…41.8 263…583 244…557 1.50…7.50 1.80…8.70 16.0…31.1 13.6…37.2 255…656 304…763 0…0.12 0.03…0.12 0…0.018 0…0.024 6.09…12.6 5.36…13.1 1.47…6.08 1.81…6.75 1.62…4.95 1.86…4.61 0.042…0.090 0.037…0.086

Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom Surface Bottom

4.30…9.90 3.10…9.90 0.40…3.80 0.50…4.70 7.58…8.67 7.34…8.66

6.70…12.0 2.40…12.1 0.70…3.90 0.40…3.90 8.03…8.67 7.75…8.69

Oxygen, mg/dm 3

BOD5, mg/dm 3

рН, pH unit

0…438 0…72

0…201 0…174

Ammonia nitrogen, μg/dm 3

148…1355 224…1333

254…1759 244…1538

Total nitrogen, μg/dm 3

0…73.0 0…15.0

0.60…28 0.60…26 0…110 8.20...85

Mineral phosphorus, μg/dm 3

15.0…210 18.0…400 10.0…1617 23.0…2500 0…0.43 0…0.37 0…0.056 0…0.041 0…0.69 0…0.51 0…19.0 0…27.0 0…8.80 0…6.60 0.10…11.0 0…14.0

Total phosphorus, μg/dm 3

96.0…4736 15.0…3544

Dissolved silicon, μg/dm 3

0…0.22 0…0.61 0…0.173 0...0.270

Oil products, mg/dm 3

Surfactants, mg/dm 3

0...0.0023 0...0.0022 7.49…16.4 7.47…18.4 1.52…4.98 2.93…6.75 1.67…4.33 1.81…4.92

– –

Total PAH, μg/dm 3

1.70…113 2.30...95.0 3.90…94.0 3.40…90.0 0.30…65.0 0.30…25.0

Zinc, μg/dm 3

Nickel, μg/dm 3

Copper, μg/dm 3

65