Denmark Assessment of Discharges, Spills and Emissions from Offshore Oil and Gas Installations in 2013 -17
This report presents the discharge, spill and emission data from offshore oil and gas operations on Danish Continental Shelf (DCS) over the period 2013–2017 and the assessment of the data. The annual data is provided in the Appendix 2.
Level of Activity
The Danish Continental Shelf is a mature oil and gas province within the OSPAR region and production is declining. However, there is still a moderate level of oil and gas production, although this has decreased by almost 15 % in the reporting period from 2013 to 2017, which is partially due to shut down and refurbishment of some installations.
Discharges & spills
The total quantity of dispersed1 oil (aliphatic oil) discharged to sea from produced water and displacement water fluctuated somewhat with a low of 162 tonnes in 2014 up to 200 tonnes in 2016 but overall remained fairly stable during the period of 2013–2017.
Produced water and displacement water discharges are the main contributors to the oil discharges from the petroleum industry. The total volume of produced water and displacement water discharged remained stable between 2013 and 2017.
A maximum of 2 installations on the DCS failed in 2015 to meet the performance standard for oil content as an annual average. The maximum amount of oil discharged with produced water exceeding the performance standard was 0,3 tonnes in 2015.
The total number of oil spills less than 1 tonne to sea increased to a high in 2014 but decreased thereafter during the period. The quantity of oil released was generally low but was unusually high in 2014 due to 3 incidents where larger quantities were spilled.
The total quantity of chemicals reported used offshore varied over the period. In 2013, 40.150 tonnes of chemicals were reported used. Of this, only 0,38 % belonged to the category “substitution chemicals”. 22 kg of chemicals on the OSPAR List of Chemicals for Priority Action (LCPA) were used in 2015 by one operator.
The total quantity of chemicals discharged into the sea over the period 2013 – 2017 varied slightly from approx. 13.300 tonnes to 15.900 tonnes. Of these chemicals only 0,07% belonged to the substitution chemicals category in 2013. This amount rose to 0,33 % in 2017 mainly due to DK re-classification of sodium hypochlorite. No LCPA substances were discharged during the period.
The number of smaller chemical spills to sea was relatively high although the quantity of chemicals spilled decreased during the period from 2013 to 2017. The number of larger spills remained low but there was a peak in the quantity spilled in 2015 due to a specific incident at one installation.
Atmospheric emissions are not regulated by OSPAR measures, but they are reported annually to OSPAR. There was a downward trend between 2013 and 2017 for the atmospheric emissions of CO2 while the emission of nmVOC and methane were fairly stable during the period. Emissions of sulphur dioxide and NOx fluctuated with a peak in 2016 but subsequently went down to a low in 2017.
1. “Aliphatics” and “aromatics” are defined by the reference method set in OSPAR Agreement 2005-15 (Solvent extraction, Infra-Red measurement at 3 wavelengths). In that context, “aliphatics” and “dispersed oil” mean the same thing