Annexure-I (Annexure-I)

Annexure-I is a supplementary schedule appended to India's effluent discharge standards that sets out additional parameters and conditions not fully detailed in the main numerical table. The general effluent standards table lists most parameters as numbers (BOD, COD, metals, etc.), but certain characteristics — such as colour, odour, and some qualitative or special conditions — are addressed through annexures and accompanying notes rather than a single mg/L figure.

The role of such annexures is to handle the parts of effluent quality that do not reduce neatly to one number. Colour, for example, may be specified by requiring removal of visible colour or meeting a maximum colour unit, and odour by an offensiveness criterion; these qualitative-but-important characteristics are exactly the kind of things annexures and notes cover. Annexures also house industry-specific or condition-specific provisions referenced from the main standards.

For recyclers, Annexure-I and similar schedules matter because compliance is defined by the full standard, not just the headline numbers. An effluent can meet every numerical parameter and still breach a colour or odour condition specified in an annexure — coloured effluent from certain plastic-washing or dye-contaminated streams, or odorous effluent from organic processing, are realistic examples. The annexure conditions are part of the consent and are enforceable.

The practical relevance is procedural: when reading and complying with effluent standards, a recycler must check not only the main parameter table but also the annexures and notes that the consent or the standard references, because conditions for colour, odour and special cases live there. Overlooking an annexure condition is a common way a plant that believes it is compliant on "the numbers" gets a notice. The actionable point is to read the complete standard, including its schedules, when designing the ETP and interpreting the consent conditions.