Carrot peels. Spud skins. And a sludge of turkey drippings. Such holiday leavings each year end up in the kitchen sink from Thanksgiving through Christmas, clogging the nation's largest sewer, Los Angeles sewer officials say. "It's wild," said Kent Carlson, a wastewater collection supervisor for the Bureau of Sanitation. "Beginning with Thanksgiving, everyone gets their cholesterol levels up in the season of family and big eating, with comfort food, gravy and taters. "It's like our arteries -- we start having problems." The Bureau of Sanitation works two shifts daily, seven days a week, to keep 6,500 miles of sewer lines...