e) the abundance and diversity of benthic fauna and the content of selected
aliphatic and aromatic hydrocarbons.
3. In order to monitor the consequent effects of the exploration phase of the offshore
activity studies, at least those referred to in sub-paragraph d) above, shall be carried out
before and after the operation.
4. In order to monitor the consequent effects of the exploitation phase of the offshore
activity studies, at least those referred to in sub-paragraphs d) and e) above, shall be carried
out before the operation, at annual intervals during the operation, and after the operation has
Regulation 4; Discharges on the exploration phase
1. The use of oil-based drilling mud or muds containing other harmful substances shall be
restricted to cases where it is necessary for geological, technical or safety reasons and only
after prior authorization by the appropriate national authority. In such cases appropriate
measures shall be taken and appropriate installations provided in order to prevent the
discharge of such muds into the marine environment.
2. Oil-based drilling muds and cuttings arising from the use of oil-based drilling muds
should not be discharged in the Baltic Sea Area but taken ashore for final treatment or
disposal in an environmentally acceptable manner.
3. The discharge of water-based mud and cuttings shall be subject to authorization by the
appropriate national authority. Before authorization the content of the water-based mud must
be proven to be of low toxicity.
4. The discharge of cuttings arising from the use of water based drilling mud shall not be
permitted in specifically sensitive parts of the Baltic Sea Area such as confined or shallow
areas with limited water exchange and areas characterized by rare, valuable or particularly
Regulation 5; Discharges on the exploitation phase
In addition to the provisions of Annex IV the following provisions shall apply to discharges:
a) all chemicals and materials shall be taken ashore and may be discharged only
exceptionally after obtaining permission from the appropriate national authority in
each individual operation;
b) the discharge of production water and displacement water is prohibited unless its
oil content is proven to be less than 15 mg/l measured by the methods of analysis
and sampling to be adopted by the Commission;
c) if compliance with this limit value cannot be achieved by the use of Best
Environmental Practice and Best Available Technology the appropriate national
authority may require adequate additional measures to prevent possible pollution
of the marine environment of the Baltic Sea Area and allow, if necessary, a
higher limit value which shall, however, be as low as possible and in no case
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