If the Department determines that additional controls are necessary to avoid an unreasonable impact on any wetland or waterbody due to pollutants that are not adequately addressed by the standards described in Section 4, astormwater project subject to this Chapter that results in three acres or more of impervious area or 20 acres or more of developed area, or requires a Site Law permit or permit modification may be required to use additional controls. This is a case-by-case determination based upon factors such as the size, nature and intensity of the development, characteristics of the affected natural resource, topography and soils.
06- 096 C.M.R. ch. 500, § 5