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SWMP Guidance • • Page 11 <br />prohibited. Therefore, management or tenants may have no knowledge of them. Cross-connections via broken <br />tines or stoppages aze also possible. <br />mere are several methods of determining whether or not illicit connections exist. Acceptable procedures include <br />dry weather observations of outfalls or other appropriate locations, analysis and validation of accurate piping <br />schematics, dye tests, etc. <br />For your facility, describe the medtod(s} used, how and when it was applied, and the results of the investigation. <br />Depending upon the complexity of the storm drainage system, this process may include a combination of more <br />than oae of [he methods. Your SWMP most include a certification statemen[ on this item. <br />Note - if illicit connections are discovered, corrective measures must be taken. <br />Method 1 -Dry Weather Observations <br />During dry weather conditions, observe storm drain outlets doting normal operating hours when an illicit <br />dischazge would be expected to be presem. If there aze flows visible, there taay be such connections. Make note <br />of all observed flows, stains, sludges, oil films, or abnormal conditions. When such flows aze found, additional <br />tests will be required to determine dte source(s). At industrial sites with lazge drainage areas, observed flows <br />could be a result of groundwater seepage, <br />This method is best suited for small sites without well-developed storm drainage systems. If [here aze no storm <br />inlets and all discharge is conveyed above ground, this process is a simple observation to verify that there are no <br />eeposed outlets from floor drains, etc. <br />_.~t at the outlet of the drainage system if it is accessible. If not, start at the farthest point downstream that the <br />system is visible. If dischazge is observed, possible sources can be determined by [hen viewing upstream inlets <br />and grates. Copies of the drainage system schematics aze very useful. <br />Method 3 -Review and In~ecrion of Schematics <br />Obtain any "as bunts" available on the storm drainage system and buildings. Review them cazefully to determine <br />where flow from floor drains and toileu goes. This review should be accompanied by field inspection to verify <br />that the "as bunts" aze accurate and to determine whether any unrecorded pipe connections exist. <br />McLOd 3 - Dve Tec c <br />Dye tests aze a very effective means of determining where flow from a certain location goes. Environmentally <br />safe dyes are available which turn fluorescent green or orange in water. Release a quantity of dye into a suspected <br />source and run water into it from a hose or tap long enough to determine where it flows. View downstream <br />outlets or inlets where the flow would be visible. Viewing sanitary sewers at manholes will provide verification <br />that the inlet is connected to the sanitary system. Many storm drainage systems can have a significant amount of <br />interaal storage capaci[y, which needs to be overcome before flow from a dye test would be visible. Therefore, it <br />may be more practical [o conduct dye [gists during or soon after wet weather to help overcome this problem. Two <br />people aze usually required for this test: one to apply the dye at the source, and the other to view the system <br />downstream. <br />hod ? - TV Line Surveys <br />This me•.hod is the most costly and would therefore most hkeiy be a last resort, used when aH odter methods aze <br />