The following described substances, materials, waters or waste shall be limited in discharges to municipal systems to concentrations or quantities which will not harm either the sewers, wastewater treatment process or equipment, will not have an adverse effect on the receiving stream, or will not otherwise endanger lives, limb, public property, or constitute a nuisance. The Director may set limitations lower than the limitations established in the regulations below if in his opinion such more severe limitations are necessary to meet the above objectives. Deliberate dilution with unpolluted water to meet the concentrations established in the regulations below shall not be acceptable. In forming his opinion as to the acceptability, the Director will give consideration to such facts as the quantity of subject waste in relation to flows and velocities in the sewers, materials of construction of the sewers, the wastewater treatment process employed, capacity of the wastewater treatment plant, degree of treatability of the waste in the wastewater treatment plant and other pertinent factors. The limitations or restrictions on materials or characteristics of waste or wastewater discharged to the sanitary sewer which shall not be violated without approval of the Director are as follows:
(a) Wastewater having a temperature higher than 150°F.
(b) Wastewater containing more than 100 milligrams per liter of petroleum oil, nonbiodegradable cutting oils, product of mineral oil origin, or floatable oils, fat, wax or grease.
(c) Any garbage that has not been properly shredded. Garbage grinders may be connected to sanitary sewers from homes, hotels, institutions, restaurants, hospitals, catering establishments or similar places where garbage originates from the preparation of food in kitchens for the purpose of consumption on the premises or when served by caterers.
(d) No discharger shall discharge wastewater containing concentrations of the enumerated materials which exceed the following values:
Maximum Daily 30-Day Average Material Concentration (mg/l) Concentration (mg/l) Arsenic - total (As) - 14.2 Cadmium - total (Cd) 1.24 1.24 Chromium - hexavalent (Cr6+) 5.21 3.32 Copper - total (Cu) 25.4 - Cyanide - total (CN) - 13.1 Lead - total (Pb) 13.9 10.2 Mercury - total (Hg) 0.0050 0.0007 Nickel - total (Ni) 11.8 6.08 Silver - total (Ag) - 2.76 Zinc - total (Zn) 32.0 18.8 |
These concentrations may be changed as necessary by the Director or state regulatory agencies based on new information concerning inhibitory substances or to protect treatment plant processes. Industrial discharges covered by federal pretreatment requirements shall meet those limitations specified under the effluent guidelines published under Sections 302(b) and 307(b) of the Federal Act and the above concentrations. Major contributing industries discharging incompatible pollutants into the public sewers shall be regulated as provided in Section 925.31.
(Ord. 117-1993. Passed 6-14-93.)
(Ord. 117-1993. Passed 6-14-93.)