The operators' own annual reporting of emissions to air and discharges to sea is carried out in accordance with rules stipulated by the authorities, and is a parallel process to the Norwegian Pollution Control Authority (SFT), the Norwegian Petroleum Directorate (NPD) and the Norwegian Oil Industry Association (OLF). New this year is that the operators report their figures directly into the EnvironmentWeb database.
Goal of zero environmentally harmful discharges
During the course of 2005, there shall be a reduction in the discharges of oil and environmentally hazardous chemical substances on the Norwegian shelf. The NPD, OLF and SFT all agree on the work to attain the goal of zero environmentally harmful discharges. Last year's figures for production discharges are a step in the right direction, while accidental discharges showed a negative trend. The oil companies have planned further reduction measures to achieve the goal.
Production discharges to sea
Produced water: There is always some water that accompanies oil that is produced. The volumes increase as fields mature. In 2003, 11 percent more produced water was reported as compared with 2002. The discharges amounted to 135 million cubic meters (m3).
Oil in water: The water that comes to the platforms with the well stream is either pumped back into the reservoir, or cleaned and discharged to the sea. According to the companies' reports, the average concentration of oil in the discharges of produced water was reduced from 21.6 milligrams per liter (mg/l) in 2002 to 16.9 mg/l in 2003. This is largely the result of measures implemented by the companies, although it cannot be ruled out that the transition to a new analysis method in 2003 may also have affected the results. The impact of the change in analysis method is being investigated.
Production emissions to air
Carbon dioxide (CO2): The companies' own reports show that the direct emissions of CO2 from combustion processes on the Norwegian shelf in 2003 were 11.4 million tons, nearly the same as in 2002. Total emissions of CO2 in Norway in 2003 amounted to 42.7 million tons.
Volatile organic compounds (VOC): Last year's emissions amounted to 172,298 tons. The emissions were reduced by about 50,000 tons compared with the previous year. The reason for this is the introduction of new technology to accommodate stricter emissions requirements in connection with loading and unloading oil offshore.
Consumption and discharge of drilling fluid
Water-based drilling fluid: Consumption in 2003 increased compared with 2002. The consumption is the same as in 2001, although the discharges show a somewhat smaller increase.
Oil-based drilling fluid: Consumption in 2003 increased compared with the previous year, while the total volume of cuttings and drilling fluid disposed of has declined. The volume of injected cuttings and drilling fluid was reduced, while the volume taken to land last year increased by nearly 10 percent compared with 2002.
Synthetic drilling fluid: The decline in consumption continued last year, and discharges in 2003 were cut by nearly 50% compared with the previous year.
Discharge of chemicals from drilling and production
Chemicals: The total discharge of chemicals amounted to 130,000 tons in 2003. This is a decline of about 26 percent compared with 2002. Of this, approx. 118,000 tons were chemicals that are not regarded as having any significant impact on the environment when they are discharged to the sea. Of the remaining 12,000 tons of chemicals, about 650 tons (approx. 0.5 percent) fall within categories that may only be discharged when there are weighty technical or safety reasons for doing so, or that the operators are required to replace with other chemicals that can reduce the likelihood of a harmful impact on the environment.
Oil: 877 cubic meters (m3) were released in connection with accidental discharges last year, compared with 109 m3 the previous year. The increase is mainly due to a discharge of 750 m3 crude oil from the Draugen field on Haltenbanken. SFT has filed charges with the police against Norske Shell ASA in connection with this discharge. Even without this incident, however, the accidental discharges were higher than previously.
Chemicals: 961 m3 of chemicals were discharged last year, compared with 344 m3 in the previous year. The increase is largely due to a few major incidents.
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