A pile of shredded tires, Friday, May 13, 2016, at the Sioux Falls Sanitary Landfill west of Sioux Falls. The Sioux Falls Sanitary Landfill uses the shredded tires to bed pipes at the landfill used for gas collection. The South Dakota Department of Environment and Natural Resources is trying to reduce the chances the mosquito-carried Zika virus shows up here by working with local landfills, including the Sioux Falls Sanitary Landfill, to prevent water from pooling in discarded tires.