There is no safe level of lead in drinking water, but a zero goal, though laudable, is at present an unattainable goal. The policing of lead in drinking water is generally in the hands of the local utility company until testing reveals lead levels higher than 15 ppb (parts per billion) in 10% of the samples collected in the distribution system. This means the action level for remedial action is 15 ppb. The frequency and number of samples collected is determined by the service population of the utility, history of analysis results, and the success of remedial measures, if they prove to be required. Remedial measures may be avoided by implementing some measures as ongoing treatment regimens, whether there is a problem or not. The chief remedial or preventive actions involve implementing and maintaining a corrosion control program to prevent leaching of regulated metals, such as lead and copper, into the product.