Arbejdsrapport fra Miljøstyrelsen, 25/2005 – Fællesdeponier til bortskaffelse af forurenet oprensningsmateriale fra danske havne

Fællesdeponier til bortskaffelse af forurenet oprensningsmateriale fra danske havne

Summary and conclusions

The total capacity of confined disposal facilities for contaminated sediment (CDF) in Denmark is 12 mill. m³. The remaining capacity is estimated to approximately 8 mill. m³. The annual filling rate is estimated to 300,000 m³. A few ports have CDF capacity enough to cover there needs for a long period, whereas several ports have reported that the remaining capacity is limited.

Existing Danish CDF's are owned and operated by the local port. Most of the CDF's are only used for contaminated dredged material, which does not meet the environmental quality criteria for open sea disposal. A few CDF's are also used for disposal of clean material.

The most common Danish CDF is the near shore type enclosed by closed dykes and attached to land on one side. Five CDF's are the upland type enclosed by earth dykes and located close to the sea on low-lying land.

The regional councils (Amter) are responsible authority for issuing permissions for CDF's . The environmental protection law (chapter 5) regulates the administration of CDF. This imply that the regional councils makes environmental approval of the CDF's and establish criteria for e.g. highest and lowest concentrations of contaminants in the material to be disposed. The councils does also establish requirements for owners monitoring etc. The existing administrative system, legislation and regulation in Denmark allow establishment of regional CDF's, where contaminated dredged material from several ports and harbours can be deposited. However it should be emphasised in the legislation that disposal of dredged material in CDF's is exempted from tax.

The cost of disposal of contaminated sediment in a new 0.5 - 2 mill. m³ capacity CDF is estimated to 7 - 10 €/m³. The estimate is based on Danish and international experiences. The transport cost of dredged material is 0.15 - 0.2 €/m³/nm. The price for the dredging operation itself is not included.

The smaller and more remote located ports and harbours are vulnerable for high transport and disposal costs. Their situation can be improved by establishing one or more private or government owned companies, which is made responsible for maintenance dredging, transport and disposal of dredged material including operation of sufficient CDF capacity. Such a company could achieve considerable discounts through international tendering for environmental investigations, bathymetric surveying, maintenance dredging, transport and disposal in ports and harbours covering an entire region. The small harbours could thereby achieve the same cost benefit as larger ports.