[Character of the big-city municipal waste water bacterial contamination and assessment of its elimination degree as a result of biological treatment process].

The highest possible effectiveness of sewage treatment is of particular significance when the sewage is discharged into surface waters used for recreational purposes. The Gulf of Gdańsk, with its much frequented beaches along the shore, is the disposal reservoir for the wastewater from two large biological treatment plants collecting the sewage from Gdańsk and Gdynia. The purpose of this work was to perform bacteriological examination of the communal sewage from these two large agglomerations before and after their biological treatment.

Evaluation of methods of sewage treatment on board of vessels on the basis of surveys in 1994-1999.

The purpose of the present study was to show in what degree the ships of the Polish merchant fleet observe the obligations provided for Poland by acts of good will of nations, i.e. International Convention for the Prevention of Pollution from Ships -MARPOL 73/78 - Annex IV, and the Helsinki Convention.

Suggestion for a physical-chemical assessment of the sea coastal waters pollution on the basis of the analysis of the examination on the Gdańsk Bay waters.

The study presents the results of physical-chemical examinations of the coastal water of the Baltic Sea, carried out from 1984-1988 on 18 sampling stations located in the region of Gdynia and Gdańsk, and along the Hel Peninsula. The samples were collected weekly from the surface of water in the distance of about 5 m from the shore during 5 years. The results indicated a considerable physical and chemical pollution of the coastal water of Gdańsk Bay.