環境保護主任（廢物及水質分科）的主要職責是（a）就管制土地或水污染與監理和處置廢物，協助擬備政策和立法建議、工作守則、指引、程序、標準、指標及策略；（b）規劃和推行有關土地或水污染的研究、管制計劃和方案和調查及測量；（c）協助研究發展液體廢物處理及處置設施，並協助研究發展和管理固體廢物設施；（d）就廢物監理與處置及土地或水污染事宜，在推行和執行法定管制方面，組織和提供專業資料，包括：處理許可證申請；及就檢控與上訴個案收集、整理和提交證據；（e）就廢物監理及土地或水污染事宜提供意見，並就與廢物監理及土地或水污染有關的評估，提供專業資料；以及（f）透過各類方法，例如擬備和介紹教育及宣傳資料，向市民和社會賢達傳達廢物管理和水質管理政策及策略。

An Environmental Protection Officer (Waste and Water Stream) is mainly deployed to (a) assist in the preparation of policy and legislative proposals and in the development of codes of practice, guidelines, procedures, standards, objectives and strategies in relation to the control of land or water pollution, and waste management and disposal; (b) plan and implement land or water pollution studies, control schemes and projects, and investigations and surveys; (c) assist in studies for the development of liquid waste treatment and disposal facilities and the development and management of solid waste facilities; (d) organise and provide professional input in relation to the implementation and enforcement of statutory controls on waste management and disposal and land or water pollution, including the processing of applications for permits, and the collection, collation and presentation of evidence in prosecution and appeal cases; (e) give advice on waste management and land or water pollution issues, and provide professional input to project assessment with regard to waste management and land or water pollution issues; and (f) assist through various means, such as the preparation and presentation of educational and publicity materials, in conveying waste management and water quality management policies and strategies to the public, and to prominent community representatives.