Caspian Sea: State of the Environment 2019

Table 5.8 continued

Concentration in 2017

Background concentration

Indicator

Horizon

Contemporary **

Historical *

Filanovsky Field

Korchagin Field

2.23…6.28 2.73…6.60 0.17…1.07 0.16…1.06 10.3…23.1 9.2…19.5

0.81…7.69 0.92…7.94 0.19…1.28 0.08…0.88 10.0…22.4 10.0…23.5

Surface Bottom Surface Bottom Surface Bottom

0.30…27.0 0.50…23.0 0.01…1.80 0…1.90 5.00…24.0 4.70…29.0

0…16.0 0…22.0 0…6.80 0…5.10

Lead, μg/dm 3

Cadmium, μg/dm 3

– –

Barium, μg/dm 3

* LUKOIL-Nizhnevolzhskneft n.d. ** Roshydromet data (Monakhov 2014a; Monakhov 2014b; Monakhov 2015) Source: Kuzin 2018.

range. Compared to the historical background, the concentration of surfactants in the water has increased, but not above the contemporary re- gional background level. This indicates that there has been a general increase in the surfactant load in the Northern Caspian. The increase in the concentration of oil products in the water close to oilfield production facili- ties, which was identified in 2016–2017, was also within the limits of the background level and was observed in other parts of the Northern Caspi- an. Given the changes in hydrological conditions (high flood in 2016, prolonged flooding in 2017), the most likely cause is an increase in the discharge of oil products with run-off from the Volga River. A comparison of the variability of the main in- dicators of chemical composition and marine pollution close to oil and gas facilities indicat- ed an increase in pollutant concentrations. The increase in the concentration of oil products in the water close to oilfield production facilities, which was identified in 2016–2017, was also ob- served in other parts of the Northern Caspian. According to Roshydromet data, the discharge of oil products in the Volga River reached 50,000 tons per year in 2016, a level three times higher than the average for 2001–2015. Currently, sea- water in the coastal areas of the Russian Feder- ation sector of the Caspian Sea are assessed as “moderately polluted” and “polluted”, and in the open sea as “moderately polluted” and “clean”

Sea (Monakhov 2014a; Monakhov 2014b; Mon- akhov 2015). It should be noted that in the open sea, these observations were carried out following a 20- year gap. Data from monitoring conducted by LUKOIL-Nizhnevolzhskneft from 1998 to 2009 (before the Korchagin oilfield, the first oilfield in the Russian part of the Caspian Sea, was com- missioned) were used to assess marine pollution during this gap. Taken together, these data describe the histori- cal (LUKOIL-Nizhnevolzhskneft n.d.) and con- temporary (Monakhov 2014a; Monakhov 2014b; Monakhov 2015) regional background pollution of the open sea, and allow the impact of oil and gas production facilities on seawater quality to be assessed. It should be borne in mind that the his- torical background describes the state and pol- lution of the marine environment before the oil- fields were commissioned, and the contemporary background describes the state and pollution of the marine environment after commissioning, but beyond the scope of the potential impact of production facilities on the marine environment. A comparison of the variability limits found in the main indicators of chemical composition and marine pollution in the areas around oil and gas facilities in 2017 with the historical and modern background data demonstrated that the values of most indicators remain within the background

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