An Area of Critical Environmental Concern (ACEC) is established under MGL ch. 21A Section 2 (7). Pleasant Bay and Inner Cape Cod Bay have been so designated. The landward extent of the Inner Cape Cod Bay ACEC is the 10-foot contour. The landward extent of the Pleasant Bay ACEC is the 10’ contour plus 100 feet. The additional 100 feet beyond the 10’ contour included with the Pleasant Bay ACEC is important in reducing anthropologic effects to the water body such as siltation from erosion caused by increased runoff from pavement and buildings or pollution from hydrocarbons or pesticides in the runoff. For the same reasons, this additional protection is also necessary for the Inner Cape Cod Bay ACEC. The natural components of both ACEC’s include barrier beach systems, dunes and sandy beaches, acres of salt marsh, productive shellfish habitat, large estuaries, anadromous fish runs, floodplain, and extensive areas for boating and swimming. The estuaries are habitat for upland species and waterfowl as well as a spawning and nursery ground for many marine species. The beaches, dunes and marshes protect adjacent upland from storm damage.