Environment Report 2014

The volume of produced water that is discharged to sea from offshore installations varies over the year, correlating with the variations in production. In 2013, produced water volumes declined between July and September, coinciding with the offshore summer maintenance period.

1

Figure 2: Monthly Discharge and Reinjection of Produced Water in 2013

2

Total Water Volume

Volume of Water Reinjected

Production 2013

16

8

3

14

7

12

6

4

10

5

4 Water Million m 3 6 8

4

5

3

2

6

2

1

Production Million Tonnes

0

0

7

Source: EEMS June 2014, DECC, Oil & Gas UK

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3.2.2 Produced Water Composition – Oil Content Produced water mainly comprises water but it does contain small amounts of other naturally occurring substances from the reservoir, such as dispersed oil, dissolved organic compounds, naturally occurring radioactive material (NORM) and traces of chemicals added during production. Any components commonly discharged in produced water rapidly dilute at sea. The chemical composition is determined by the reservoir geology and may also change during the reservoir’s production life. In 2013, the volume of oil discharged with produced water was 2,176 tonnes or 0.001 per cent of the total volume of produced water.

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