A former gravel pit became the Brookings city landfill after the City bought the property in 1960. For the first 10 years, most trash was burned, and the ash and non-burnable garbage was buried. In 1971, the City began disposing of trash above ground as a landfill, and a mound started to form as trash was trucked to the site, compacted, and covered daily with gravel mined from adjacent pits. For more than 20 years, the trash rose higher while the gravel pits grew larger and deeper. The landfill closed in 1993 and was sealed with a clay cap the following year. After topsoil was stripped away, a dragline mined gravel and dug pits eight to fifteen feet deep, which became the park's chain of ponds.