Oceanographic data from the Environmental Impact Assessment of the Davis Sewage Outfall

Untreated, macerated wastewater effluent has been discharged to the sea at Davis Station since 2005, when the old wastewater treatment infrastructure was removed. This environmental assessment was instigated to guide the choice of the most suitable wastewater treatment facility at Davis. The assessment will support decisions that enable Australia to meet the standards set for the discharge of wastewaters in Antarctica in national legislation (Waste Management Regulations of the Antarctic Treaty Environmental Protection Act - ATEP) and to meet international commitments (the Madrid Protocol) and to meet Australia's aspirations to be a leader in Antarctic environmental protection. The overall objective was to provide environmental information in support of an operational infrastructure project to upgrade wastewater treatment at Davis. This information is required to ensure that the upgrade satisfies national legislation (ATEP/Waste Management Regulations), international commitments (the Madrid Protocol) and maintain the AAD's status as an international leader in environmental management. The specific objectives were to:1. Wastewater properties: Determine the properties of discharged wastewater (contaminant levels, toxicity, microbiological hazards) as the basis for recommendations on the required level of treatment and provide further consideration of what might constitute adequate dilution and dispersal for discharge to the nearshore marine environment2. Dispersal and dilution characteristics of marine environment: Assess the dispersing characteristics of the immediate nearshore marine environment in the vicinity of Davis Station to determine whether conditions at the existing site of effluent discharge are adequate to meet the ATEP requirement of initial dilution and rapid dispersal.3. Environmental impacts: Describe the nature and extent of impacts to the marine environment associated with present wastewater discharge practices at Davis and determine whether wastewater discharge practices have adversely affected the local environment.4. Evaluate treatment options: Evaluate the different levels of treatment required to mitigate and/or prevent various environmental impacts and reduce environmental risks.

自2005年旧废水处理设施拆除以来，戴维斯站（Davis Station）一直将未经处理的粉碎废水排放至海洋。本次环境评估旨在为戴维斯站选择最合适的废水处理设施提供指导，其结果将支持澳大利亚达成以下目标：符合国家立法中关于南极废水排放的标准（《南极条约环境保护法》废物管理条例——ATEP）、履行国际承诺（《马德里议定书》），以及实现澳大利亚成为南极环境保护领域领导者的愿景。评估的总体目标是提供环境信息，为戴维斯站废水处理升级这一运营基础设施项目提供支持，确保该升级项目满足国家立法（ATEP/废物管理条例）、国际承诺（《马德里议定书》）的要求，并维持澳大利亚南极局（AAD）在环境管理领域的国际领先地位。具体目标包括：1. 废水特性：测定排放废水的特性（污染物浓度、毒性、微生物危害），作为推荐所需处理等级的依据，并进一步考量何种稀释与扩散程度足以支持向近岸海洋环境排放；2. 海洋环境的扩散与稀释特征：评估戴维斯站附近近岸海洋环境的扩散特征，判断现有排放点的条件是否满足ATEP关于初始稀释和快速扩散的要求；3. 环境影响：描述当前废水排放实践对海洋环境的影响性质与范围，确定该排放实践是否已对当地环境造成不利影响；4. 处理方案评估：评估为缓解和/或预防各类环境影响、降低环境风险所需的不同处理等级。