Coastal Water Authority-grantor of pedestrian and bicycle easement

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~? 4. ~1 ~r ~~I I l 1 l~ ~ \J~I r~1 illij 'i!l /!, ~~ ~~ condition is not created. A one-foot (1') lift of cement stabilized sand may be required in the bottom of the excavation to provide a good footing for temporary support of the tapping valve and concrete placed support. 3. Control of Ground Water - The hot tap contractor shall provide the necessary measures to control the ground water from all sources. Since the bedding and pipe zone backfill for the CW A pipelines is sand, there is a potential for any groundwater present to run along the CW A pipelines into the excavation for the hot tap. The hot tap contractor shall provide the necessary measures to control the groundwater without the loss of pipe bedding material. Valves - The tapping/gate valve shall be in accordance with AWWA C500 or C509. The tapping valve shall be provided with a valve support prior to tapping. Gate valves shall have a ductile iron body, 125 lb. flat-faced, flanged ends, cast iron double disc gate, bronze trim, non-rising stem, extension rod, a two-inch (2") A WW A square operating nut in lieu of an operating wheel, and a by-pass valve to equalize the pressure on both sides of the gate valve. CW A requires an additional valve (butterfly valve) for isolation on taps 24 inches and larger. The butterfly valve shall be in accordance with A WW A C504. Taps less than 24 inches can be provided with only a gate valve (RESILIENT- SEATED) in accordance with AWWA C509. Butterfly valves shall have a ductile iron body, Class 150B, short body valve with flanged ends, ductile iron disc, stainless steel seats and shaft, non-rising stem, extension rod, and a two-inch (2") A WW A square operating nut in lieu of an operating wheel. Bolting for all valves shall be in accordance with ASTM A307, Grade B with hexagonal heads. All buried valves shall be provided Page 5 of 16