Natural History. A member of the weasel family, the sea otter is the smallest marine mammal in North America. The southern, or California, sea otter ranges along the coast from San Mateo County southward through Monterey County and down to Santa Barbara County.Unlike other marine mammals, sea otters don't have a thick layer of blubber. member of the weasel family, the sea otter is the smallest marine mammal in North America. The southern, or California, sea otter ranges along the coast from San Mateo County southward through Monterey County and down to Santa Barbara County. Unlike other marine mammals, sea otters don't have a thick layer of blubber.
In modern plumbing, a drain-waste-vent (or DWV) is part of a system that removes sewage and greywater from a building, and regulates air pressure in the waste-system pipes to aid free flow.t the building drain system's lowest point, the drain-waste vent is attached, and rises (usually inside a wall) to and out of the roof. Waste exits from the building through the building's main drain and flows through a sewage line, which leads to a septic system or a public sewer.
Sections of the stack. A combination of vertical pipes with fittings forms the stack in a plumbing waste system. It is used for waste disposal and venting. The main stack is composed of three sectionsthe soil stack, waste stack, and vent stack.A soil stack carries waste disposal from water closets. Start at the building sewer pipeline and work towards the place where stack will be installed. 2  Set the pipe to a grade slope of inch per foot with a carpenters level. 3  The slope will rise from the building sewer line to the stack. 4  Support the pipe at each connection to maintain the grade slope.