Site plan reviews are performed to evaluate commercial, industrial, and multi-family development proposals prior to construction. These are typically required when an existing use that does not conform to local zoning laws is being expanded or changed to another use. Local site plan review regulations are typically implemented by planning boards in communities where the local legislative body (e.g. town meeting) has granted that authority and the municipality has both a zoning ordinance and subdivision regulations.
Site plan review can cover a wide range of issues surrounding the relationship between the proposal and the surrounding area. Among those issues is the management of existing and potential threats to groundwater and surface water.
Site plan review regulations include standards for site design. Among those standards, the planning board will probably include compliance with applicable state laws as well as local zoning laws. Since state BMP (Best Management Practices) rules for potential contamination sources apply throughout the state (even outside wellhead or groundwater protection areas), local planning boards can help ensure that those BMPs are being implemented through site plan review. DES can also offer recommendations in addition to the BMPs. For example, DES recommends that local officials discourage or prohibit direct infiltration of storm water from industrial and petroleum-related sites within groundwater protection areas.
Site plan review occurs before a site is developed or expanded, or the use changed. If necessary, the planning board would typically place conditions on approval of a site plan to ensure that groundwater resources are adequately protected. If those conditions are violated, the municipality may take enforcement action as with any zoning violation.