Surface Layer above Contaminated Sludge Pool with
Innovative Materials in Kotka Harbour
Ekokem-Palvelu Oy carried out a construction project in which
massive amounts of innovative materials were used to build a new
port area over dredging pool. Kotka has several large harbours that
operate rapidly growing transit traffic to Russia. One of the most
common goods stevedored in Kotka are cars. Adjacent to Kotka
Hietanen port was 35 hectares large dredging pool, where sludge
contaminated by dioxins from Kymi river have been disposed. In the
project an intermediate parking lot was built over the dredging
pool with crushed coarse and recycled waste materials.
The lowest part of area was 10 - 20 m deep layer of contaminated
dredging sludge that was covered by filter cloth. Because the
lowest layer is soft, the layer above had to be soft as well. The
next layer consists of altogether 100 000 - 150 000 m
3 chips that are grained of tires and massive amounts of
industrial by-products that are primarily ashes. The topmost part
consists of several layers of crushed gravel and sand. The lot is
covered by asphalt. Because the amount of available used tires from
Finland was insufficient for the needs of project, large amounts of
tires had to be imported as well. The area is right at the coast
and had to be isolated from sea by sheet pile wall structures.
The area was nesting place for aquatic birds. The project was
designed and implemented in a manner that nesting and resting of
migratory birds was not disturbed. During The construction project
reached two main targets, to expand the port area and to utilise
waste materials in a sound manner.