Lead and Copper are regulated by the Safe Drinking Water Act, under the Lead and Copper Rule (LCR). Lead and Copper samples are obtained from residential customers with lead service lines, lead solder or premise-plumbing lead components. IDEM requires CBU to sample for Lead and Copper every three years. The Action Limit for Lead is 15 ug/l and 1300 ug/l for Copper. Micrograms per liter (ug/l) is equal to parts per billion (ppb). One part per billion is roughly equal to a teaspoon of water in an Olympic-size swimming pool.