The main raw material for cement and lime production is shellsand sourced from the ocean floor. Shellsand is dredged from the seabed at Owen Anchorage and landed at Woodman Point (pictured below) where it is washed to remove salt and silt and then pumped as a slurry to a stockpile at the Munster Plant.
Cockburn Cement has been dredging shellsand from Owen Anchorage since 1972 under the terms defined in the Cement Works (Cockburn Cement Limited) Agreement Act (1971). Cockburn Cement currently dredges under an approval dated 2002 in which the WA Minister for Environment granted permission for Cockburn Cement to dredge shellsand from areas of low seagrass biodiversity in Owen Anchorage for eight years. The company now has approval to dredge from areas of West Success Bank until 8 July 2030. Current and future dredging areas are free of seagrass. Under its current approvals, Cockburn Cement is not allowed to dredge areas with seagrass.
Our work in Owen Anchorage has also previously been used by the
State Government to help develop a second shipping channel into
Cockburn Sound and to widen the existing shipping channel. Since
1994 we have spent over $8 million on rehabilitation of
seagrass and research into the environmental impacts of dredging
These operations are the subject of the Environmental Management Programme (EMP) detailed in this section.