Whenever a wastewater or storm water sample is obtained for analysis, a chain of custody form must be completed and retained for the length of time required by the relevant water discharge permit or regulation. If there is no time limit specified in the permit or regulation, recordkeeping requirements must be followed as required by the Corporate Records Retention Schedule. The laboratory must provide a chain of custody form. The attached form contains an example chain of custody and the minimum required information that must be included in a chain of custody form.