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Each of the 25 core samples will also be tested using the Chang and Jackson phosphorus <br />speciation technique. This technique divides sediment phosphorus associations into the <br />following categories ($75/sample): <br />a. Saloid Phosphorus C. Aluminum -Bound Phosphorus <br />b. Iron -Bound Phosphorus <br />7. Internal recycling of phosphorus: Direct measurements of internal recycling of <br />phosphorus under oxic and anoxic conditions will be performed in Queens Mirror Lake <br />and South Lake Triplet by collection of large diameter (-10 cm) sediment core samples <br />from various locations within the lakes. Two separate core samples will be collected in <br />Queens Mirror Lake and South Lake Triplet (4 total) from a variety of water depths and <br />sediment characteristics. The core samples will be returned to the ERD Laboratory and <br />incubated under both oxic and anoxic conditions. Sediment release of phosphorus will be <br />measured in each column over time. Filtered water samples will be collected periodically <br />from each core chamber for a period of 30 days under both oxic and anoxic conditions. <br />The release rate information will be combined with current and historical dissolved <br />oxygen measurements to evaluate phosphorus recycling on a seasonal basis based on the <br />percentage of oxic and anoxic zones within the lake. A total of 80 samples will be <br />collected (4 chambers x 10 samples/chamber x 2 conditions) and analyzed during the <br />testing program for the following parameters ($25/sample): <br />a. SRP ($10) <br />b. Total Phosphorus ($15) <br />8. Watershed delineation / hydrologic modeling: Delineation of watershed areas will be <br />conducted for Queens Mirror Lake and each of the Triplet Lakes using available stormsewer <br />and topographic information. Estimates of annual runoff inputs to the lakes from each of <br />the contributing watershed areas will be developed using computer modeling techniques. <br />The modeling will be performed using site-specific hydrologic characteristics for each <br />drainage sub -basin area, including basin size, percentage of impervious areas, soil <br />characteristics, and conveyance system types. Estimates of annual runoff inputs to the lake <br />will be generated for each contributing sub -basin area. <br />9. Develop hydrologic budget: Annual hydrologic budgets will be developed for Queens <br />Mirror Lake and each of the Triplet Lakes based upon evaluated inputs from direct <br />precipitation, stormwater runoff, and groundwater seepage. Inputs from direct precipitation <br />will be calculated based upon the lake surface area and historical rainfall characteristics for <br />the Central Florida area. Hydrologic inputs from stormwater runoff will be estimated based <br />upon computer modeling of the drainage sub -basin areas. Inputs from groundwater seepage <br />will be estimated based upon the field monitoring program. If direct measurements for <br />these inputs are available, either from historical data or the field monitoring program, then <br />these values will be used. If direct data are not available, then hydrologic components will <br />be estimated based on similarities with other lakes or conditions. The results of the <br />hydrologic budget will be presented in both graphical and tabular formats. <br />PROPS \QUEENS MIRROR/TRIPLET CHAIN -OF -LAKES HYDROLOGIC -NUTRIENT BUDGET EVALUATION FEE -AUGUST 2010 PAGE 5 <br />