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e a COOPERATIVE EXTENSION UNIVERSITY OF CALIFORNIA DAVIS, CALIFORNIA 95616 REPLY TO:Dept. of Land, Air and Water Resources Voice: 916-752-2533' Fax: 916-752-1552 E-mail: gspettygrove@ucdavis.edu May 12, 1994 Mr. L.H. Lehmann 3234 Roberts Rd. Stockton, CA 95206 Dear Mr. Lehmann: I received your letter and attached information about applying the sugar rinse water to seven acres of land. I compared your proposed loading rate to guidelines for BOD (biochemical oxygen demand) loading rates in the U.C. leaflet Land Application Systems for the Utilization of Fruit and Vegetable Processing Effluent (UC Division of Agric. Sciences Leaflet 21252). BOD is a measure of the decomposable carbon content of the water or waste. Too much BOD would exceed the capacity of the normal aerobic soil microorganisms to decompose the waste. This would result in the development of anaerobic conditions leading to foul odor and accumulation of various organic compounds that are harmful to plants and -- if there were runoff into surface waters -- harmful to fish. The suggested guideline is 10 to 25 lbs BOD/acre per day. The authors cite studies in which higher loading rates were used, apparently with no problem. The actual BOD that the soil can process will depend on the soil type, amount of water applied, and temperature. Where the soil is well drained and a resting period is provided, BOD loading can be higher than the cited guidelines. Your proposed rate is 6000 gallons on 7 acres per month. The solution'is 4% sugar. Assuming that 1 lb of sugar provides 1 lb of BOD, and that the water is applied uniformly over the 7 acres, you would be applying 9.7 lb BOD/acre per day. Since the amount of liquid you are applying is insignificant, it should not create anaerobic conditions which might slow the decomposition and allow the accumulation of odor-producing compounds. My calculation is based on the sugar rinse water. If you are already applying other BOD-containing wastes to the same land, you would need to consider the total amount of decomposable organic matter being added. Also, of course I am assuming the waste does not contain harmful contaminants in high levels, such as detergents, acids, lye, brine, etc. With these assumptions in mind, I conclude that your proposed application should not cause any problem. Indeed, the addition of decomposable carbon can benefit the soil because the bacteria which degrade the sugar will produce polysaccharides and other compounds that can improve soil aggregation and physical condition. Also, the addition of high carbon, low University of California and the United States Department of Agriculture cooperating.