The effect of Scott Base waste water discharge on the marine benthic community

To determine if the Scott Base waste water discharge has any effect on the marine benthic community, the benthic community was surveyed, tissue samples were collected from bivalves and water samples were analysed for faecal coliform bacteria from two sites, Pram Point (where the outfall is located) and Cape Armitage (some distance away). The benthic community survey was conducted to determine community assemblage. This data set is reported in another data set, see related data link. Bivalves are known to accumulate toxins in tissues and hence represent a useful indicator of long term environmental conditions. Ten Limatula hodgsoni were collected from each of the two sites at Cape Armitage and Pram Point and immediately frozen for analysis of tissue concentrations of heavy metals and hydrocarbons. Water samples were taken from shallow (5m) and deep (25m) regions in the water column at both sites on three occasions. Each of the five 500ml replicate samples from each station was filtered through 0.2µm minisart filters and incubated at 37°C for 24 hours. Colonies were counted and coliform densities estimated. No coliforms were recorded from any of the samples and no evidence was found to suggest that the Scott Base waste water discharge was having a detrimental effect on the benthos. One possible impact of Scott Base was observed. The steep incline of the reef meant that loose rubble tumbled down very easily. Some areas looked as if rocks had fallen from above as scour marks appeared on the reef slope. This is most likely from bulldozing activity around the base, moving sediments and rocks to the edge of the land ice transition. It is suggested that bulldozed material should be kept away from the cliff edge.