環境保護主任（水質數學模型）（廢物及水質分科）的主要職責是–
（a） 開發、覆檢、維護及應用水質及水動力的數學模型系統；
（b） 開發及管理有關水文、水質及污染資料記錄的地理訊息系統；
（c） 評估及應用有關水質及水文數據分析的數學方法和統計法；
（d） 規劃及推行有關水質及水動力模型的研究、調查及測量工作；
（e） 就廢物管理及土地或水污染事宜提供意見，並在水質及水動力模型項目的評估上，提供專業建議；
（f） 管理部門電腦設施；
（g） 就土地或水污染的管制與廢物的管理和處置事宜，協助擬備政策和立法建議，並制訂工作守則、指引、程序、標準、指標及策略；
（h） 策劃及推行有關土地或水污染的研究、管制計劃和方案及調查和測量工作；以及
（i） 透過各類方法，例如擬備和介紹教育及宣傳資料，向市民和社會各界别代表傳達廢物管理和水質管理政策和策略的訊息。

An Environmental Protection Officer (Water Quality Modelling) (Waste and Water Stream) is mainly deployed to –
(a) develop, review, maintain and apply mathematical water quality and hydrodynamic models;
(b) develop and manage geographic information system on hydrology, water quality and pollution inventory;
(c) evaluate and apply mathematical methods and statistical techniques in water quality and hydrologic data analyses;
(d) plan and implement water quality and hydrodynamic modelling studies, investigations and surveys;
(e) give advice on waste management and land or water pollution issues, and provide professional input to project assessment with regard to water quality and hydrodynamic modelling;
(f) manage departmental computer facilities;
(g) 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;
(h) plan and implement land or water pollution studies, control schemes and projects, and investigations and surveys; and
(i) 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 various community representatives.