12/15/2009 SEWER COMMISSION Minutes

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� 4 0.3 8 was met by scenario 3 and 4. The infaunal habitat target range of 0.4 and 0.5 ppm TN was met in Scenario 3 for Mashpee River, and Shoestring and Ockway Bay was met in all scenarios. Scenario Results-Eastern Waquoit Bay Mr. Eichner reported there are eel grass targets for Hamblin and Jehu Ponds but that historically, no eel grass has been present in Quashnet or Moonakiss River. Quashnet and Moonakis have infaunal targets. Total nitrogen thresholds are depicted for Jehu, Hamblin and Quashnet in the chart. Mr. Eichner reported that, as with Popponesset, shaded and bold areas meet the TMDL thresholds. Scenarios 1, 2, 4 and 5 meet the threshold for Jehu and Hamblin. At 0.52, Quashnet River is very close to meeting the infaunal target only through Scenario 4 at 0.523, which rounded, would meet the threshold. Additional Issues to Consider As noted in his previous presentation, Mr. Eichner reminded attendees that there are additional issues to consider, such as the use of alternative septic systems described in Scenario 3. In reference to the 306,000 figure that has been disputed, Mr. Eichner stated that SMaST provided all information to Lombardo Associates prior to entering the water quality phase, so they are surprised that it would be a different number. Mr. Eichner suggested that if more flow is not going to clusters, it will impact the water quality analyses. Mr. Eichner also discussed the wastewater effluent nitrogen concentration assumed in the scenarios versus what would be approved by DEP. He additionally discussed how the current discharge of existing wastewater facilities would be considered in future scenarios. Finally, Mr. Eichner noted the potential for natural nitrogen attenuation and the reduced flow requiring treatment. Ouestions&Discussion Mr. Fudala noted that the confusion involving the 306,000 number needs to be resolved. In addition, Mr. Fudala questioned whether or not 10 would be approved by the DEP. Mr. Fudala stated that the Sewer Commission's goal was to develop a plan that,based on existing or proposed plants, would reduce the total kg of nitrogen traveling to the bays to meet the TMDL targets. Mr. Fudala expressed concern that despite demonstrating that the plants achieve 5.7 the DEP might not approve it if they feel the plants should get 10, which is a regulatory maximum and not an average number. Mr. Fudala questioned how to satisfy the DEP and the possible need to monitor sentinel stations for a lengthy period. i Mr. Fudala reported that the next phase of the assessment will involve ensuring that everyone is satisfied with the numbers and the model, prior to narrowing down the scenarios. Mr. Eichner added that appropriate concentrations should also be considered. Mr. Fudala announced that he would like the 306,000 number sorted out prior to the next meeting which will be held in Meeting Room 3 on January 21. At that time, Mr. Fudala hopes to narrow down the scenarios to an affordable option that meets the target as well as an option that would be most affordable over the long term. Brian Howes, also of SMaST, agreed that the effluent concentrations needed to be resolved before additional scenarios could be considered. Mr. Howes noted that MA DEP has written permits for annual loads, which would resolve some issues regarding the CWMP. Mr. Howes noted that the question becomes what is the true effluent concentration expected on a flow weighted average. Mr. Fudala noted that he would like the numbers based on history. Mr. Howes uses numbers provided to SMaST and added that the next step should be using numbers from the town. Secondly, Mr. Howes pointed out that different scenarios have different results and that perhaps the reallocation of load removal should be a consideration when reviewing the scenarios. Mr. Howes stated that modeling . 3