Table 113

Environmental factors affecting hydrocarbon exploration and exploitation in the Ross Sea (from Holdgate and Tinker, 1979; ┬╗additions from Zumberge, 1982).

Factors that Influence Site Selection

Geological indications of oil potential Bathymetry and structure of the sea bed Iceberg and pack ice condition and distribution Currents (surface and deep) Climate - weather

Special biological features of site (and alternatives) Cost of operation

Technological Factors that Influence Impacts

Use of seismic explosives Drilling procedures and processes Nature of rigs or platforms

Nature of well head completion structure (e.g., on or below seabed)

Nature of oil storage system (e.g., seabed or shore-based tank farm)

Nature of transport system (ship, submarine, pipeline)

Nature of pollution control system (including training and management)

Nature of emergency procedures (including training)

*Short season and limitation on drilling of relief well(s)

*Lack of timely and accurate ice-climate and weather forecasting

Environmental Factors Affecting Impact

Types and concentration of pollutants released (e.g., oil, condensate, gas, drilling mud, sewage, domestic garbage) Rates of physical and biological degradation of hydrocarbons and other pollutants Rates and direction of dispersion and dilution of hydrocarbons and other pollutants Relative locations of accidental, incidental and deliberate releases and living targets (e.g., benthos, sea-ice microbial community, phytoplankton, krill and zooplankton, fish, seals, whales, seabirds, etc.) Sensitivity of living targets to hydrocarbons and other pollutants and to substances used in clean-up operations would rapidly self-cleanse of any impacting oil through vigorous wave action and the abrasive effects of drifting ice (Gregory et al., 1984a). Similarly, there would be no significant retention of oil on rocky shores, whether low, glacially muted bluffs or high precipitous cliffs (Fig. 11.14), for these also would self-cleanse. In addition, landfast sea ice and a protective ice foot would further shield these shores from drifting oil.

Beaches, which are mostly composed of coarse granule sands and pebble-to-boulder-sized material constitute less than 5% of the entire coast of the western Ross Sea (Figs 11.12 and 11.13), and most are occupied by Adelie Penguin rook-

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