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.
A waste stack carries waste disposal from all other fixtures. A vent stack provides air circulation throughout the waste system and allows for the release of sewer gases. Placement of the stack. The stack runs in the building wall, up through each floor, and out through the roof. 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.