The primary activities, functions and responsibilities are based on as per provisions of the Acts & Rules, and the Board has been performing following activities within the State of Arunachal Pradesh

Comprehensive programme on Water, Air, Land etc., Pollution Control and Execution thereon.
Advice and liaison with the State Government on any matter concerning environmental pollution.
Collection and dissemination of data and information on pollution and environmental problems and preparation of reports thereon.
Investigation and research relating to pollution and environmental problems.
Collaboration with the programmes of the Central Pollution Control Board, Ministry of Environment and Forests, State Government, NGOs and other organizations relating to pollution control and environment and organize Mass Education Programmes.
Issue of N.O.C. and Consent to industries and other development projects.
Inspections of sewage, trade effluent sites, industries, various industrial, plants and Sewage Treatment Plants.
Monitoring of industrial/trade effluents, water bodies, air and soil, and laboratory analysis thereon.
Laying down or modification of effluent and emission standards.
To evolve economical and reliable methods of treatment of sewage and effluent.
To establish or to recognize laboratories for performing functions under the Acts and Rules.
Assessment and collection of Water Cess.
Environmental education to public, students and others, and publication of mass-education materials.
Advise the State Government regarding location of industries, etc.
Enforcement of the provisions of the aforesaid rules and monitoring thereof.