Table 10-13.—TroubIeshooting Effluent Disposal

Table 10-13.—TroubIeshooting Effluent Disposal—Continued INDICATOR LIKELY CAUSES ACTIONS TO TAKE Effluent sus- pended solids content too high. Effluent pH too low or too high. Wastewater organisms killed, very little treat- ment being pro- vided. Coliform count above permit requirement. 1. Secondary units organi- cally overloaded. 2. Hydraulic overload. 1. Industrial discharges not properly pretreated. 2. Septic conditions in col- lection system or in the treatment plant. Toxic material leaking or being discharged to the col- lection system. 1. Not enough chlorine being applied. 2. Chlorine not well mixed with the wastewater. 3. Contact time too short. 1. Keep organic loading of secondary units within design capacity if reasonably possible. Carefully inspect aerated units for DO con- tent and mixing. 2. Same action as for too many settleable solids in the effluent due to hydraulic overload. 1. Inspect and sample the wastewater from the collection system to find the source. Require or provide proper pretreatment. 2. Inspect both collection system and plant for detention time in sewer pipes, wetwell, and clarifiers. Clean and flush clogged or partly clogged sewers. Aerate and/or chlori- nate the influent wastewater for temporary relief. Immediately notify downstream users and regulatory authorities, giving all available information as to type and quantity of toxic substance, also time of release. If the operator has advance warning of a spill or discharge of toxic waste, then all available storage should be used to contain the toxic material instead of letting it pass through the plant. If it cannot be contained, use all available methods to neutralize and/or dilute the toxic waste. Try to find the source of the toxic material and use every reasonable means to prevent its discharge to the system. 1. Test several times daily for “free” chlorine residual, especially during and immediately after peak flows. Adjust dose of chlorine according to test results. Inspect chlorine feed pump for working condition. If chlorine com- pounds such as HTH and others are being used, be sure of its percentage of chlorine con- tent when adjusting the feed rate (dose). 2. Inspect mixing equipment to be sure the chlorine and wastewater are well mixed immediately. Test for free chlorine residual in several areas of the contact tank to be sure of proper mixing. 3. Carefully check the contact (detention) time of the tank to be sure that 15 to 30 minutes’ contact time is provided. Remove sludge deposits, if any are present, from the contact tank. 10-31