Section 26A. Unless the context otherwise requires, when used in sections twenty-six to fifty-three, inclusive, the following words shall have the following meanings:

''Abatement facilities'', facilities for the purpose of treating, neutralizing, or stabilizing sewage and such industrial and other wastes as are disposed of by means of the facilities, including treatment or disposal plants, the necessary intercepting, outfall and outlet sewers, pumping stations integral to such facilities and sewers, equipment and furnishings thereof and their appurtenances.

''Board'', the board of certification of operators of wastewater treatment facilities.

''Collection system'', each and all of the common lateral sewers and appurtenances of publicly owned treatment works which are primarily installed to receive wastewaters from individual structures or from private property, and which include service connection ''Y'' fittings and service connections within the boundary of the public way or easement.

''Commissioner'', the commissioner of the department of environmental protection, or his authorized designee.

''Director'', the director of the division of water pollution control, or his authorized delegate or representative.

''District'', a district created pursuant to section twenty-eight.

''District commission'', the governing body of a district.

''Effluent limitation'', a requirement, established under state or federal law, specifying the maximum permissible quantity or concentration of any pollutant that may be present in discharges, or their maximum permissible hydraulic flow, over designated periods of time, to waters of the commonwealth or to a public sewerage system.

''FWPCA'', the Federal Water Pollution Control Act, 33 U.S.C. §§ 1251 et sequens, as amended.

''Green infrastructure'', practices involving the management of water, stormwater and wastewater to achieve water quality mandates set forth in the federal Clean Water Act; practices designed using natural or engineered techniques to capture, remove or prevent nutrient, nitrogen and phosphorous loading to any part of a water system including groundwater deposits and discharges to surface waters from septic systems, wastewater treatment facilities and stormwater runoff.

''Green infrastructure projects'', projects which shall include, but shall not be limited to: decentralized wastewater systems that infiltrate treated water; water reuse for other beneficial purposes; low impact development projects; the conservation, enhancement and restoration of natural landscape features that naturally filter and remove silt and pollution from surface waters, maintain or restore natural hydrologic cycles, minimize imperviousness in a watershed through preservation and restoration of natural landscape buffers such as forests, floodplains, wetlands and other natural systems and restoration of natural stream channels; land acquisition and restoration projects that protect and filter drinking water supplies and buffer reservoirs; and the mitigation of risks of flooding and erosion using the restoration of saltmarsh, oyster reefs and eelgrass beds from sea-level rise, storm surges and extreme weather events, including the protection and restoration of natural coastal landscapes; provided, that green infrastructure projects may be stand-alone and shall also be used to complement built water management infrastructure technologies such as pipes, dikes and treatment facilities; and provided, further, that green infrastructure projects may include innovative technologies that further the mandates under the federal Clean Water Act.

''Person'', any agency or political subdivision of the commonwealth, public or private corporation or authority, individual, partnership or association, or other entity, including any officer of a public or private agency or organization, upon whom a duty may be imposed by or pursuant to any provision of sections twenty-six to fifty-three, inclusive.

''Pollutant'', any element or property of sewage, agricultural, industrial or commercial waste, runoff, leachate, heated effluent, or other matter, in whatever form and whether originating at a point or major nonpoint source, which is or may be discharged, drained or otherwise introduced into any sewerage system, treatment works or waters of the commonwealth.

''Priority list'', the ranking, in terms of priority, of projects eligible for funding during a given planning period, which has been established pursuant to the priority system.

''Priority system'', the methodology for rating and ranking projects eligible for grant assistance under sections thirty A and thirty-three of this chapter and for establishing priority lists for those projects.

''Public entity'', any city, town, special district, or other existing governmental unit eligible to receive a grant for the construction of treatment works from the United States Environmental Protection Agency pursuant to Title II of the FWPCA, as amended.

''Treatment works'' and ''facilities'', any and all devices, processes and properties, real or personal, used in the collection, pumping, transmission, storage, treatment, disposal, recycling, reclamation or reuse of waterborne pollutants.

''Waters'' and ''waters of the commonwealth'', all waters within the jurisdiction of the commonwealth, including, without limitation, rivers, streams, lakes, ponds, springs, impoundments, estuaries, coastal waters and groundwaters.