§ 60 Discharge of produced water
Produced water shall be cleaned prior to discharge to sea.
The oil content in produced water discharged to sea, shall be as low as possible, cf. Chapter II of the Framework Regulations and Sections 7 and 8 of the Management Regulations. In any event, the oil content shall not exceed 30 mg oil per litre of water as a weighted average for one calendar month.
On facilities that discharge produced water, the operator shall perform environmental risk assessments of the discharges. These shall be performed as soon as possible after produced water is available. New risk assessments shall be performed in case of significant changes in the discharge or in any event minimum every five years. The Norwegian Environment Agency can set more explicit requirements to implementation and frequency of environmental risk assessments and discharge of produced water. Documentation associated with performed risk assessments shall be made available to the Norwegian Environment Agency upon request.
Water treatment systems shall be designed and operated such that the environmental strain from discharges to sea will be as low as possible also if the discharge limitations, cf. the second subsection, can be met with reduced treatment effect. The operator shall establish and maintain a best practice for operating and maintaining the processing system, comprising treatment units incorporated in the system on the individual facility.
The operator shall regularly assess possible technical solutions that can reduce the environmental strain from discharges of oily water. Documentation associated with such assessments shall be made available to the Norwegian Environment Agency upon request.
The operator shall take appropriate measures to limit potential damage to the external environment from oil pollution in cases where discharge of produced water involves visible oil on the sea surface. The obligation under this subsection applies to measures that are in reasonable proportion to the damage and inconvenience to be avoided.
The Norwegian Environment Agency and the Norwegian Radiation and Nuclear Safety Authority can set additional requirements regarding discharges of produced water.
Section last changed: 01 February 2019
The operator must obtain a permit from the Norwegian Environmental Agency for petroleum activities under Chapter 3 of the Pollution Control Act (in Norwegian only). Application for permit under the Pollution Control Act is subject to Chapter 36 of the Pollution Control Regulations (in Norwegian only), and a fee is fixed for the Environmental Agency’s processing relating to applications for permits pursuant to Chapter 36 of the Pollution Control Regulations (in Norwegian only).
The regulations’ general requirements for the petroleum activities on the continental shelf apply to all operators. The permits under the Pollution Control Act will normally contain conditions that are specific and adapted to each activity. Chapter 36 of the Pollution Control Regulations (in Norwegian only) gives further provisions on the processing of permits under the Pollution Control Act. The Norwegian Environment Agency has described further expectations for the content of applications and expected processing time in the Guidelines for applications regarding offshore petroleum activities, TA-2847-2011. Chapter 39 of the Pollution Control Regulations (in Norwegian only) gives provisions for fees for work with permits.
Section 11 of the Framework Regulations describes principles for risk reduction, including requirements regarding the use of best available techniques (BAT).
The Management Regulations set specific requirements for follow-up and improvement in Sections 19-23, including requirements for continuous improvement. In addition, the Norwegian Environment Agency shall be informed in case of changes in risk of pollution cf. Section 34 subsection one, litera b of the Management Regulations.
Oil content as mentioned in the second subsection, means content of dispersed oil in undiluted water decided in accordance with Section 70.
In accordance with principles of risk reduction and management (Chapters II and III of the Framework Regulations and Chapter II of the Management Regulations), the responsible party shall establish a management system that ensures compliance with the HSE regulations and continuous improvement. This entails that the responsible party shall establish and develop goals and strategies for compliance with the regulatory requirement to keep the oil content as low as possible. Section 55 of the Facilities Regulations does also state that facilities for treatment of produced water shall be designed in such a way that oil content in each discharge is as low as possible.
OSPAR Recommendation 2012/5 is implemented in Norwegian legislation in Section 60 of the Activities Regulations. The Recommendation includes requirements to perform risk assessments on discharge of produced water, and that best available measures shall be selected in order to reduce risk.
Risk assessments should be performed with methods based on expected environmental concentrations and expected non-harmful concentrations (PEC/PNEC) on substance level. The method based on Environmental Impact Factor may be used.
“Significant changes in the discharge of produces water” mentioned in third subsection, includes:
- the introduction of new measures expected to have an impact on the risk level, for example reinjection, chemical substitution and treatment measures
- increased discharges as a result of changes in injection rate
- significant changes in the composition of produced water, for example as a result of inclusion or exclusion of well streams or chemicals
- 50 % changes in amount of oil to sea, oil concentration or chemicals with significant contribution to the risk, applying to installations with EIF between 10 and 50
- 15 % changes in amount of oil to sea, oil concentration or chemicals with significant contribution to the risk, applying to installations with EIF higher than 50.
When assessing how the treatment facilities shall operate to minimize the environmental impact, the oil content of the discharge shall be evaluated against inter alia use and discharge of chemicals.
The risk assessments shall be reported in accordance with Section 34 litera c of the Management Regulations.
According to Section 11 of the Framework Regulations, «the responsible party shall choose the technical, operational, or organizational solution that (…) offer the best results. In addition, Section 23 of the Management Regulations and Section 15 of the Framework Regulations demand continuous improvement. Therefore, the Norwegian Environment Agency expect that the results from the risk assessment are applied further in new BAT assessments and potential measures to reduce the environmental risk for each field.
New technology assessments are performed for all installations according to the results from risk assessments, but the level of detail may depend on the magnitude of the risk contribution or the oil content in the water discharged to sea. The assessments shall include measures to reduce the total discharged volume of water, for example with techniques such as water shut-off, downhole separation and injection, as well as treatment measures.
For fields with high risk contribution or with high oil content in the water discharged to sea, detailed assessments of costs associated with the various measures should be compared to the environmental benefits. For fields with a low risk contribution, the same degree of details in cost/benefit assessments will normally not be necessary, in particular as regards implementing of expensive technology. The Norwegian Environment Agency will consider the definition of low/high risk contribution when results from risk assessments are available. When technology is available for treating other substances than dispersed oil, the Norwegian Environment Agency may require such treatments.
Technical solutions that can reduce the environmental impact of discharges of oily water, may be downhole solutions for reduced water production, reinjection or new/altered technical elements in the treatment plant, for example.Assessments should be reported in accordance with Section 34 litera c of the Management Regulations.
Chemicals following the produced water to sea after treatment, shall be covered by the permit in accordance with Section 66 first subsection. Adding chemicals that do not contain a specific function in the production or treatment process, is not allowed.
Measures as mentioned in the sixth subsection, may include monitoring of oil and seabirds, or mechanical dispersion, for example. There may also be other technical measures to reduce the visible oil on the sea surface, changing the discharge point or temporarily reduce the discharges of produced water, for example.