COMPLIANCE INFO_1990-1998 - Laserfiche WebLink

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�► • CITY OF TRACY 5 30 August 1990 SLUDGE MANAGEMENT PLAN JULY 1990 storage, and application to the land. If onsite storage at the site is required in the future, then the City is responsible for providing sludge storage facilities that meet all regulatory requirements. The City and K & L Farms have developed three options for sludge application in which the sludge would be applied during a 6-week period and incorporated within 48 hours by K & L Farms to an 8- to 10-inch depth. A description of each option is given below: Option A: Sludge would be removed periodically from the City's sludge drying beds and taken to a sludge storage facility at the New Jerusalem Airport. During a 6-week period in the fall , the City would apply the sludge to the surrounding fields at agronomic rates. The sludge storage facility would be a permanent permitted facility and could receive sludge yearround. Option B: The City would construct a summer sludge transfer station at New Jerusalem Airport. A private firm would be contracted by the City to haul the sludge from the City's drying beds to the sludge transfer station and then apply the sludge at agronomic rates during the fall . No sludge would remain at the transfer station after the fall sludge application. Option C: The City would contract with a private firm to haul the sludge directly from the City's sludge drying beds to the fields. The trucks transporting the sludge would be equipped with mechanical spreaders units (similar to manure spreaders) to uniformly spread the sludge at agronomic rates. This option would eliminate the need for a sludge storage facility at the application site. Although the sludge could be applied in the spring, the City has requested approval for Option C to apply the sludge this fall in order to avoid problems with soil compaction. In addition to the soil being dry and firm (further inhibiting soil compaction), fall tillage, which follows the harvest, is typically deeper than spring seedbed preparation and, therefore, the sludge should be more thoroughly incorporated into the soil . One potential concern with the fall application is that the nitrogen applied the sludge may leach below the root zone before it is used by the crop. However, it is not expected since the nitrogen cycle is slower during the cooler winter months. MONITORING PROGRAM In order to evaluate the performance of the sludge land treatment processes, the Report states that a monitoring program will be implemented. The monitoring program will be used to insure safe and effective performance of the system. The Report recommends that the data from the monitoring program undergo professional review each year to determine the effects of sludge application, to detect any changes in sludge quality or other environmental quality impacts, and to suggest mitigating modifications in site management. The monitoring program includes sludge, ground water, and soils monitoring. The objective of the sludge monitoring is to establish the quality of the sludge prior to application to ensure that the nutrient requirements are met and the metal loading limits are not exceeded. The Report initially recommends semiannual sludge sampling with a reduction in sampling frequency once a consistent sludge quality has been