ISDS 



Performance criteria should address treatment failure and failure of the system to adequately 

 treat waste flows, and should require treatment meeting technological design standards, 

 based on the following considerations: 



• Public health and safety considerations of inadequate pathogen removal, nitrate 

 removal, removal of toxic compounds including cleaners and solvents; 



• Environmental considerations of: 



-hydrologic modification (e.g., altering the existing water table in such a way that 



incidence of hydraulic failure increases) 

 -contributing to nutrient enrichment and potential eutrophication of receiving 



waters 

 -contributing to bacterial contamination of shellfish 

 -contributing to surface water degradation 

 -exacerbating impacts of other non-point source concerns 



***Revise ISDS regulations to establish specific criteria outlining system 

 owner's special responsibilities to avert system failure in critical areas, or 

 areas of fundamental environmental concern. Undertake an accompanying 

 education campaign to advise critical area residents as to resource vulnerability, and notify 

 them of their responsibilities. Such areas should be provided as overlays on town 

 assessors maps and zoning maps, and should be designated in the regulations as Special 

 Inspection Areas coinciding with critical area designations and Wastewater Management 

 Districts as identified. Such areas should include, for example, areas having severe soil 

 limitations for ISDS use, areas of existing ISDS contamination, reservoir recharge areas, 

 coastal areas, SAM plan areas, and all critical areas as defined in previous sections. 



***Revise ISDS regulations to define criteria to be applied as a basis for requiring ISDS 

 maintenance, repair, and replacement Guidance should be provided based on system size 

 and existing condition and should specify factors of consideration such as: 



-size and condition of system and absorption area 



-design suitability based on soil conditions 



-fiequency of malfunction 



-other relevant factors relating to public health, cumulative effects, etc. 



**Establish clear standards and specifications which system repairs must meet, (see also 

 VARIANCES) 



♦♦Revise ISDS regulations to require mandatory system upgrades for failed 

 systems. (Current DEM policy is to require upgrading to the maximum extent possible at 

 the time of failure.) In cooperation with towns, establish interim maintenance and pumping 

 procedures to apply to systems which will be included in WWMDs, if system upgrades are 

 to be provided tlux)ugh the WWMD widiin one year of regulatory revision. Using funds 

 from the SewerAVater Supply Failure Fund, and other funds as necessary, provide support 

 for system upgrades, giving first priority to systems in towns which have established 

 WWMDs. In towns having approved wastewater management plans, funding may also be 

 available firom the Environmental Trust Fund, used to match federal Construction Grants 

 funding. 



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