ISDS 



Recommendations 



*Permit use of mounds as replacement systems in critical areas where 

 conventional repair or replacement of failed systems is impracticable. 

 Mounds should not be permitted as an alternative to conventional systems 

 for new housing construction except as specified within strictly controlled pilot 

 programs in key public water supply watershed areas. 



* Prohibit use of mounds where existing depth to groundwater does not exceed two feet or 

 where depth to an impervious layer does not exceed four feet under natural soil conditions. 



**Devebp specific design, construction, and maintenance standards for mound systems as 

 outlined in the ISDS Task Force Subcommittee Report on Alternative Systems. 



*Prepare a Rhode Island Siting, Design, and Construction manual for mound systems as 

 outlined in the ISDS Task Force Subcommittee Report on Alternative Systems. 



PACKAGE PLANTS 



Findings and Concerns 



DEM is presendy developing a regulatory strategy to address issues surrounding 

 development of package sewage treatment plants. Although regulatory language is not yet 

 in place, DEM operating policy is to discourage development of package plants in new 

 developments due to monitoring and maintenance problems. Experience in other states 

 indicates that these plants can significantiy degrade resources and can concentrate waste at 

 one discharge point where health hazards can result if treatment has been incomplete. In 

 Rhode Island, DEM is under particular pressure to allow construction of package plants to 

 serve subdivisions in rural areas, where monitoring and maintenance problems and 

 establishment of accountability would be most severe. 



Major issues raised as a result of experience in other states include: 



• maintenance, operational and monitoring problems that are the inherent outcome of 



the proliferation of small treatment facilities; 



• water quality impacts that could result from the failures of such small treatment 



facilities. Package plants are particularly susceptible to toxic contamination; 



•environmental impacts of package plants in marginal areas; 



• growth and planning of the use of package treatment plants for new single family 



residential development in areas previously considered unbuildable; 



• financing, ownership, and replacement issues; and 



• sludge management and disposal. 



Package plants also raise complex regulatory issues. New discharges will have to be 

 regulated under DEM water quality regulations to ensure compliance with water quality 

 standards. Plant compliance with regulatory standards will in turn depend on proper 



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