D/DBP规则中强化混凝的定义包括基于原水TOC和碱度的TOC去除目标。这些目标TOC清除量被称为“第一步”要求。或者，如果这些目标TOC清除量不能作为合理费用实现，该规则将允许降低TOC清除水平。这些替代性TOC清除被定义为“步骤2”要求。本文概述了强化混凝处理技术的第一步要求。另一方面，第2步要求被定义为去除TOC的“收益递减”。收益递减标准的幅度任意设定为每10 mg/L增量明矾（Al2（SO4）3，18，H2O）剂量减少0.3 mg/L TOC。 在同等基础上，这意味着每增加5.5 mg/L三氯化铁（FeCl3）剂量，总有机碳减少0.3 mg/L。此外，美国环保局预计，即使不满足TOC增量去除标准，公用事业公司也不会仅因添加混凝剂而将混凝pH值降低到所示水平以下。如果在这些pH值下不能满足TOC增量去除标准，则公用事业公司无需追求超过该点的强化混凝。

The definition of enhanced coagulation in the D/DBP Rule includes TOC removal targets based upon raw water TOC and alkalinity. These target TOC removals are termed as "Step 1" requirement. Alternatively, the Rule will permit lower levels of TOC removal if these target TOC removals could not be achieved as reasonable expenses. These alternative TOC removals are defined as the "Step 2" requirements. A summary of the Step 1 requirements of the enhanced coagulation treatment technique are presented. Step 2 requirements, on the other hand, are defined as "diminishing returns" for TOC removal. The magnitude for the diminishing returns criteria was arbitrarily set at 0.3 mg/L of TOC reduction per 10 mg/L of incremental alum (Al2(SO4)3, 18,H2O) dose. On an equivalent basis, this translates to 0.3 mg/L TOC reduction per 5.5 mg/L of additional ferric chloride (FeCl3) dosage. Further, USEPA does not expect a utility to reduce the coagulation pH as a result of coagulant addition, alone, below the levels indicated, even if the incremental TOC removal criterion is not satisfied. If the incremental TOC removal criterion cannot be satisfied at these pH values, then the utility need not pursue enhanced coagulation beyond this point.