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and caused problems. Mr. Braginton-Smith stated that such problems do not occur when AIRVAC <br /> assists with the initial design and communication is direct between the involved parties. <br /> Mr. Klenert noted the high velocity in the system and the need to reinforce the pipes and Mr. <br /> Braginton-Smith confirmed that a detailed spec of the sawtooth profile allows for the effected <br /> mitigation of the linear momentum so that the flow changes direction smoothly. Mr. Klenert <br /> questioned the maximum lift to which Mr. Braginton-Smith responded that 30 feet is the maximum <br /> height to lift water by vacuum and the sawtooth profile uses gravity along with a 1 foot rise on an <br /> angle. Mr. Klenert questioned the energy needed to operate the vacuum pumps and whether they are <br /> centralized in one area. Mr. Bragin ton-Smith stated that a vacuum station can cover an area of 2 miles <br /> in every direction. Mr. Lyons questioned the number of gallons per day that a station would handle. <br /> Mr. Braginton-Smith responded that the tank is designed to accommodate the aggregate flow at a <br /> maximum load potential but that a typical installation in a dense community could manage 1 '/2 million <br /> gallons per day. Regarding the number of pits in a particular community, W. Braginton-Smith stated <br /> that some communities may have only 150 but that Plum Island has 660 and Provincetown has 600 <br /> pits. The Chair referenced the proposal distributed to Commissioners that contains specific flow <br /> information for Mashpee. <br /> Chairman Fudala noted the advantage of not needing electricity at each home to operate the system but <br /> questioned the ability to expand the system as needed, suggesting it as another means to manage land <br /> control. At the Chair's suggestion, Mr. Braginton-Smith clarified the 4 h of July situation in <br /> Provincetown stating that the system had been originally designed for a system other than the vacuum <br /> system and noting that the engineer did not understand the nuances of the system_ Consequently, <br /> problems with the system occurred. Mr. Braginton-Smith described a condominium complex in the <br /> east end of Provincetown with a 500 gallon sump flowing into a valve designed to handle 10 gallons <br /> creating the potential for problems. Although the amount of flow was drowning the system, it <br /> recovered for some time until there was a major event in town. Additionally, when the event occurred, <br /> operators had difficulty locating the problem area and did not shut down the east end of the system to <br /> reduce the impact. Mr. Braginton-Smith reported that Barnstable has added vacuum pressure sensors <br /> at the end of the line in order to more quickly identify problems. The Chair questioned whether <br /> Barnstable's system was properly designed and Mr. Braginton-Smith described issues of increased <br /> flow following rain events, determining that residentially owned sump pumps were adding rainwater to <br /> the sewer systems. <br /> The Chair asked if operators can be hired to operate the system_ Mr. Braginton-Smith responded that <br /> his company is a fully certified AIRVAC service center. Tom Burns questioned the longevity of the <br /> valves and Mr. Braginton-Smith described the parts of the valve using an example of the valve and <br /> stating that any parts requiring replacement are easily removed and replaced in the field. The Chair <br /> asked if the valve pit can communicate with a central location. Mr. Braginton-Smith stated that <br /> sensors are available and can be placed in the pit, but that it is recommended to place the sensors at the <br /> end of the line to monitor any drop in pressure. Mr. Braginton-Smith described the way in which a <br /> problem valve could be identified. Mr_ Malarkey questioned the availability of complementary <br /> services and whether a signed contract is needed and Mr. Braginton-Smith responded that planning and <br /> design would be complementary. <br /> STEP Sewer Systems-Orenco Systems <br /> The Chair referenced materials provided in packets to the Commissioners about STEP systems. <br /> Michael Dunne of Wastewater Technologies, a representative for Orenco Systems Inc., also provided a <br /> packet of materials to the Commissioners. Mr. Dunne reported that Wastewater Technologies has been <br /> in business since 1996 and has installed Orenco systems throughout New England and New York and <br /> 3 <br />