Section 096-579-4 - Determination of decision resultsA waterbody's attainment class is determined by following the process described below, and as shown in Appendices 1 and 2.
A.Assess data appropriateness and minimum requirements. The first step is to determine if the sample meets minimum requirements (Section 3(A)) and is appropriate to run through the Linear Discriminant Models (LDM). If the minimum provisions or sampling procedures are not appropriate, then professional judgment may be used to determine the appropriate course of action (Sections 3(G)(2) and 3(G)(3) ).B.Determine if sample attains at least Class C. The second step is to use the association value from the "C or better" LDM (pABC) to determine if the sample meets at least Class C or is in nonattainment of minimum aquatic life criteria. If the association value is equal to or greater than 0.6, the sample attains Class C. If the association value is less than 0.4, the sample does not attain Class C and is determined to be in nonattainment of any classification. If the association value (pABC) is greater than 0.4 and less than 0.6, then professional judgment is used to determine if the sample is (1) Class C, (2) in nonattainment, or (3) indeterminate of Class C (see Section 3(G)(1) ).C.Determine if the sample attains at least Class B. For those samples that attain at least Class C, the next step is to use the association value from the "B or better" LDM (pAB) to determine if the sample is (1) at least Class B with an association value equal to or greater than 0.6, (2) Class C with an association value less than 0.4, or (3) indeterminate of Class B with an association value greater than 0.4 and less than 0.6 (Section 3(G)(1)).D.Determine if the sample attains Class A. For those samples that are at least Class B, the final step is to use the association value from the "A" LDM (pA) to determine if the sample is:(1) Class A with an association value equal to or greater than 0.6,(2) Class B with an association value less than 0.4, or(3) Indeterminate of Class A with an association value greater than 0.4 and less than 0.6 (Section 3(G)(1) ).06-096 C.M.R. ch. 579, § 4