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8/19/2022 1:13PM
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Lime Sludge Disposal

 A byproduct of the lime softening water treatment process is lime sludge.  Lime sludge generally consists of 99.5% water with the remaining 0.5% a lime and silt mixture.  An average daily water production rate of 8 MGD (millions gallons per day) generates 500,000 gallons of lime sludge each and everyday.  To store and eventually dewater such huge quantities of lime sludge, the Water Division operates and maintains 3 lime sludge lagoons.  The lime lagoons are situated on 37 acres located off of Cedar Run Road.  #1 & #2 lagoon were built in 1964; #3 lagoon was built in the early to mid 1990s.

To address lime sludge on a regulatory basis, in 1998 the City of Newark developed a sludge management plan (SMP) for agricultural land application for the sludge generated at the water treatment plant.  The accumulated dewatered lime sludge is removed periodically from the lagoons and applied to agricultural land owned and farmed by local farmers through contractual agreement with the City.  Agricultural liming is a soil amendment technique used by the agricultural community to increase pH and to supplement Nitrogen to the soil for crop production.  The contractor hired by the City operates under a Liming Materials License permitted through the Ohio Department of Agriculture