PENGUIN HEAD OUTFALL

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Monitoring Results

# Indicator Bacteria

(TEL 1996a)

Found no effect on:

the patterns of abundance and distribution of intertidal biota at outfall location compared to the reference locations.

- on subtidal turfing algae.

- Abundance of reef fish such as hula (Trachinops taeniatus) and rock cale (Crinodus lophodon).

General findings not necessarily related to outfalls:

- invertebrates associated with subtidal turfing algae were abundant and diverse with trends in variability at Penguin Head similar to those at the reference locations.

- no organochlorines were detected in any of the fish analysed, while the levels of heavy metals were within recommended guidelines for human consumption.

Methods:

TEL (1996a) carried out a marine ecology assessment on a single sampling occasion in 1995. Three habitats were investigated, each in relation to appropriate reference habitats within 20km of Penguin Head. These habitats were intertidal rock platforms; fish, sea urchins and abalone; and invertebrates associated with subtidal turfing algae. Visual methods (using quadrats) were used to quantitatively survey four intertidal rock platforms (measuring abundances and cover of invertebrates and algae). Subtidal habitats at penguin Head were surveyed using underwater visual censuses techniques along 350m long transects. Invertebrates living in dense mats of turfing coralline algae were sampled at four locations (Penguin Head and three reference locations), removed from the algae, identified to major taxonomic group and counted. Three species of fish (Red Morwong [Cheilodactylus fuscus], Blue Groper [Achoerodus viridis] and Rock Cale [Crinodus lophodon]) were collected from near the release and three reference locations and analysed for levels of organochlorines and heavy metals.

TEL 1998

Found that sewage effluent:

- increased the concentrations of phosphorous and total organic nitrogen (TKN) greater in two species of algae (kelp [Ecklonia] and bubbleweed [Phyllospora]) at Penguin Head compared to reference locations

- decreased the concentration of total solids in algae at Penguin Head compared to reference locations.

Found no effect on:

- assemblages of epifauna in turfing algae at outfall compared to reference sites.

- populations of reef fish (relatively small populations at both Penguin Head and the reference sites).

General findings (not necessarily related to outfall):

- intertidal assemblages showed a statistically significant difference in composition between times of sampling and among locations. There was no evidence to suggest that the variability in the assemblages at Penguin Head was outside the range of variability found in the reference locations.

- no organochlorines were detected in any of the fish analysed, while the levels of heavy metals were within recommended guidelines for human consumption. Only one analysis indicated an uptake of copper in fish at Penguin Head (second sampling period only) and concentrations were low.

- Assemblages of benthic organisms at penguin Head differed in their structure between 15 m and 20 m depths and between the 20 m depth and Kinghorn Point (reference location). The 15 m depth location at Penguin Head differed from Crookhaven Head (reference location). There was no evidence to suggest that these differences could be due to the outfall and The Ecology Lab (TEL 1998) concluded that both the 15 m and 20 m locations at Penguin Head were similar to those at other locations within the region.

- Fish assemblages in deeper water off Penguin Head were also similar to the reference areas.

## Methods

Tel (1998) repeated their 1995 studies along with supplementary studies and compared the results to the first sampling period. These studies involved: intertidal flora and fauna; invertebrates associated with subtidal turfing algae; rocky reef fish in shallow (<5m) water; accumulation of metals and organochlorines in fish; nutrients in algae; and benthic organisms and fish on reefs in 15-20m depth (see also TEL 1996b). Additional surveys of benthic organisms (e.g. sponges) and fish were done in deeper water off Penguin Head, which has been considered for offshore release of effluent. The taxa, number of species and abundance of species recorded were representative of benthic assemblages on rocky reefs found between 15 m and 20 m along the exposed NSW coastline.

Outfall Site

Faecal Coliform

Outfall Site

Red Morwong

Penguin Head

(Peng_7) Last updated June 2000