Considering Alternatives
Continuing to work with the DEP in February 2005 the district submitted a detailed scope of study to the DEP that outlined two core alternatives: (1) Upgrade the existing WLSD treatment plant or (2) convey the wastewater to Torrington. Costs and conceptual designs were completed for both. The upgraded plant option considered two alternatives (Sequencing Batch Reactor and Single Sludge Two-Stage Reactor) that both included vertical sand filters and both had 2005 capital costs of more than $19 million. Lateral sand filters were not offered as an option due to their significantly higher costs. If lateral gravel filters were deemed acceptable by the DEP the cost would be reduced by nearly $9 million. In 1996 the DEP approved the lateral gravel filter however its approval was later rescinded. Three different routes of conveying the wastewater to Torrington were considered. The 2005 capital costs ranged from $9.5 million to $10.8 million.