Design Guide for Community Water Systems - The Water, Sanitation ...

a. Sanitary sewers with the approval of the local wastewater systemauthority; orb. A flowing stream provided the stream flow is adequate to provide thenecessary dilution.4.11.4. Lime softening residualsLime softening residuals may be land applied at agronomic rates.Residuals from plants using lime to soften water varies in quantity and inchemical characteristics depending on the softening process and thechemical characteristics of the water being softened. These characteristicsgovern the amount of residual that can be applied to any specific piece ofground. The engineering report submitted to the department shall includea discussion of the expected residual characteristics. Methods of treatmentand disposal are as follows:a. Lagoons may be used to temporarily store residuals until they can beremoved for final disposal. Storage lagoon(s):1. Must be designed to be cleaned periodically;2. Submittals shall include descriptions and specifications onresiduals removal, handling, processing and disposal equipmentor shall include information on the arrangements with acontractor to remove and land apply the residuals.3. Submittals shall include a copy of facility specific, standard,operating procedures for residual removal and disposal. Theoperating procedures shall include a discussion of the manpowernecessary for proper operation of the facilities;4. Shall be designed to provide a total of at least six months ofresidual storage calculated on the basis of 0.7 acre per milliongallons per day per 100 milligrams per liter of hardness removedbased on a usable lagoon depth of at least five feet;5. Must have at least two but preferably more, storage cells in orderto give flexibility in operation; and6. Shall be designed to produce a wastewater effluent that meets theMissouri Clean Water Commission effluent and water qualitystandards and that is satisfactory to the department.b. Discharge of lime residuals to sanitary sewers should be avoided sinceit may cause both liquid and residual volume problems at the sewagetreatment plant and sewer plugging problems. This method shall beused only when the sewerage system has adequate capacity and abilityto handle the lime residuals.c. Disposal at a permitted sanitary land fill can be done as either a solid orliquid if the landfill can and will accept such waste, in accordance withsolid waste management regulations.d. Mixing of lime residuals with waste activated sludge may beconsidered as a means of co-disposal. All necessary approvals from thelocal wastewater system operating authority shall be obtained. Pilotstudies or trial runs to determine the impact of the lime residuals on theAug. 29, 2003Page 88