How should facilities treat “non-detects” of dioxins?
According to EPA s reporting guidance, monitoring data and emission factors determined for your facility should be reported “in a manner consistent with the methods and procedures that EPA has developed for determining if these compounds are present in various industrial processes.” If the method treats non-detects as zero (e.g., Method 1613, Method 23), then they should be reported as zero. However, if a facility has better information than is provided by these methods, that information should be used. EPA s reporting guidance states that if the method being used by a facility to detect dioxins is not an EPA approved method and the detection level being used is not as sensitive as those approved for use under EPA methods, then the facility must use “reasonable judgment” as to the presence and amount of a listed toxic chemical, based on the best readily available information. If the reportable toxic chemical is known to be present, a concentration equivalent to half the detection limit
