2. Rejection conditions

The discharge standards adopted vary widely:

• Pollution parameters are more numerous than for ERU and are specific to the industries, countries and even basins concerned.

• Legislative requirements for specific parameters (hydrocarbons, heavy metals, F, CN, AOX, phenols) depend on the measurement methods used, which can vary in severity from country to country.

Effluent may be discharged directly into the natural environment or into urban sewers leading to biological treatment plants, whose operation must not be disrupted.

While usage implies limitations on effluent concentration, we are increasingly imposing mass flows per day or per unit of product manufactured. Monthly averages and daily maximums are also considered....