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Popponesset Bay:Enhanced Natural N Removal <br /> Another example of enhanced nitrogen removal, located in Popponesset Bay, is Mashpee's oyster <br /> project. Mr. Eichner suggested a credit may be granted by the DEP for use of such enhanced nitrogen <br /> removal situations in relation to the TMDL. <br /> Sewer Commission Wastewater Scenarios-Timeline <br /> Mr. Eichner reviewed the timeline reflecting the current scenarios, beginning in April 2008 and <br /> concluding with acceptance of the database and nitrogen loads by the wastewater consultants at the end <br /> of October 2009. <br /> Sewer Commission Wastewater Scenarios <br /> Mr. Eichner reiterated the five scenarios. Scenarios 1, 2, 4 and 5 were recommended by Stearns and <br /> Wheler and Scenario 3 was recommended by Lombardo Associates. <br /> Scenario 1-No expansion of existing WWTF(wastewater treatment facilities)which currently have 10 <br /> ppm TN(total nitrogen) effluent; the addition of 4 new WWTF with 3 ppm TN effluent; 5 discharge <br /> sites and 380 I/A(innovative alternative) septic systems that would remove additional nitrogen with 10 <br /> ppm TN effluent. <br /> Scenario 2-Upgrade or expand existing facilities, as practical, reducing effluent to 3 ppm; add 4 new <br /> WWTFs with 3 ppm TN effluent;4 discharge sites; no IA systems <br /> Scenario 4-"Fair Share Discussions" includes 3 new WWTFs with 3 ppm TN effluent; 3 discharge <br /> sites; approximately 130 new I/A septic systems with 10 ppm TN effluent <br /> Scenario 5-"Centralized Approach" includes 2 new WWTFs(1 each in Mashpee and Sandwich)with <br /> 3 ppm TN effluent; 5 effluent discharge sites; convert all existing private Mashpee WWTFs to <br /> pumping stations connected to a single centralized Mashpee WWTF <br /> Scenario 3-`Nitrex Based Decentralized Approach" includes 16 VVVVTFs with 3.75 ppm TN effluent; <br /> 16 discharge sites; all new or expanded on-site septic system flow treated with on-site Nitrex with 3.75 <br /> ppm TN effluent <br /> Sewer Commission Wastewater Scenarios-Table <br /> Mr. Eichner shared a table of wastewater flows reflecting various types of technology such as standard <br /> Title V, septic systems, innovative systems, existing wastewater treatment facilities and new <br /> wastewater treatment facilities. Flow totals include both East Waquoit and Popponesset watersheds. <br /> As a result of a question from the last meeting, Mr. Eichner added to the table the total flow from the <br /> unified database of 2.7 million gallons per day. <br /> Restoration Goals <br /> Mr. Eichner questioned the impact of watershed inputs on the system and the goals of meeting the <br /> targets. Mr. Eichner reported that the ultimate goal is to restore eel grass and infaunal habitat in certain <br /> areas. 'The goals have been translated into total nitrogen concentrations which are regulatory figures <br /> through TMDL provisions. <br /> Scenario Results-Popponesset BaX <br /> Mr. Eichner presented the scenario results for Popponesset Bay, which had been discussed previously, <br /> reminding the audience the shaded and bold areas meet the MEP threshold. The eel grass threshold of <br /> 2 <br />