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MR. BEST asked Mr. Kirk what the difference is between LG-1 and NG-2 and he indicated that NC-2 allowed more uses. THE PUBLIC HEARING WAS GLOSED. A motion was made by Commissioner Marshall, seconded by Commissioner Hartwell, to refer this item to the Planning Board for a recommendation to come back to the Board no sooner than August 1st. VOTE: UNANIMOUS c. PD-1-89 McLennan's Farm 'The presentation was made by Mary Scearbo. In summary this item is to receive citizen comment on the proposal for a Planned Development-Special Use Permit for McLennan's Farm. Mr. Leon Todd submitted an application for a residential Planned Development in the Rural Buffer. The plan for McLennan's Farm includes fourteen (14) lots to be served by a community low pressure system for sewage disposal. The County contracted with Hazen and Sawyer, consulting engineers, to prepare a study on the advisability and effectiveness of alternative systems for sewage disposal. This report was presented to the Gommissioners on August 22, 19$8. COUNTY ENGINEER PAUL THAMES stated that he has reviewed the engineers plan for the alternative sewer system for McLennan's Farms. He indicated that the design of the system includes septic tanks and pump tanks for each individual house, a force main to a central pumping system and a low pressure nitrification field which is a good design in general. He did, however, have specific problems with the use of the concrete block construction for the central pumping structure in that it would be hard to waterproof. He indicated that it would be better to use one large, or a series of smaller, precast concrete septic or pumping tank type structures. The design of the lower pressure field allows the liquid to be pumped out into 3000 linear feet of piping. This will create a problem which will cause the field to fail in a short. period of time. Piping to 1000 or 1200 linear feet would be a better option. The size of the field is set at a minimum of 2.7 acres. They apparently have 2.75 total acres of satisfactory area where the low pressure field can be located. They do not have any allowance for buffers, for corrections that are necessary in the field to avoid steep slopes, or low areas where the field can hold water. Generally, between 5$ and 10~ of an overall area that is satisfactory is needed to be used for corrections due to sloping, etc. This 5~ to 10~ would put this over the 2.75 available acres. The last major problem is the way the system is proposed to be owned. Each individual homeowner will be responsible for his own individual septic tank and pumping tank. The homeowners association will own the remainder of the equipment which will be operated by a licensed utility operator. This would result in very irregular installations of individual homeowner's septic tanks, pumping systems and so forth. These will be different types of pumps and equipment. It would be better°if a licensed utility operator owned the system, including the forced mains and the individual lot's septic tanks and pumping facilities. These problems are fairly serious and if left to the existing design on the alternative system would flaw it to the extent that it would not be a reliable system. However, the problems can be solved by some adjustments to design and the way the ownership is handled. They also can increase the size of the field by cutting down the number of houses or decreasing the number of bedrooms per house. The system is sized for 120 gallons per bedroom for 3.5 bedrooms per house for 14 houses. COMMISSIONER MARSHALL referred to Paul Wilms' letter about Amberly. She indicated that she did not know how that would effect these permits in the future. She read a portion of Mr. Wilms letter which is incorporated into these minutes by reference and is