Months after the Environmental Working Group found what it declared an unsafe level of the carcinogenic chemical compound hexavalent chromium (chromium 6), the Louisville Water Company has confirmed the substance's presence in city water. But, company officials say the water is still safe to drink.Chromium 6 is not regulated. Total chromium–which contains hexavalent chromium–is regulated, and Louisville's water has safe levels of total chromium. The chromium 6 levels, however, exceed a limit for the compound that's been proposed in California. The EPA is currently researching chromium 6 and considering whether it should be regulated outside of total chromium. The agency has also encouraged water companies to test for the compound.In a statement released Friday, Water Company officials said they will follow all Environmental Protection Agency guidelines.