This refers to the “best practicable environmental option”. When it is necessary to undertake any action with environmental impacts, the different options that could be considered for the purpose must be identified and defined. The BPEO, as defined in NEMA, “means the option that provides the most benefit or causes the least damage to the environment as a whole, at a cost acceptable to society, in the long-term as well as in the short-term”. Other guidelines typically used for environmental management in terms of other legislation include: BPM which is the Best Practicable Means, BAT which is the Best Available Technology and BATNEEC which is the Best (Proven) Available Technology Not Entailing Excessive Cost.

DWAF adopted a BPEO guideline in 1991 for water quality management and in 1994 in the Minimum Requirements document for waste management. The definition however used was “the outcome of a systematic, consultative and decision-making procedure which emphasizes the protection of the environment across land, air and water”. It is suggested that the procedure in the old BPEO guideline is followed and that the result that is aimed at should be the result as described in the NEMA definition.