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which is a wide channel constructed at a slight slope that is lined with a synthetic liner, upon which attached algae will grow. Surge boxes will provide a very effective hydraulic regime for algae growth. The flow into the algal scrubber may be combined with a recycle stream taken from the scrubber' s discharge; thus, the project could also provide operational data to evaluate effluent recycling (similar to a wastewater treatment plant trickling filter operation), which will allow further fine-tuning of the system' s treatment efficiency. Discharge from the algal scrubber will be sent by gravity to the polishing pond and some of it will be routed from the polishing pond to the polishing wetland. The side slopes of the existing polishing pond will also be modified to a shallower slope for littoral planting. All treated water will be discharged by gravity back into the IRFWCD canal system. Under normal flow conditions the treated water will overflow into Lateral B-4 Canal and flow east into the Lateral B Canal. Under certain weather conditions, the water will also temporarily overflow into the Lateral C Canal. Therefore, the proposed project is a managed aquatic plant treatment system that will remove significant quantities of pollution from the IRFWCD drainage system, helping to achieve the current goal of a fifty to sixty percent reduction of pollutant loads from the IRFWCD to the Indian River Lagoon. It is also a demonstration project because it will show the benefits of a managed aquatic plant system for the IRFWCD that is operated as an agricultural process . Because farmers understand through their daily work the task of maximizing biomass, the concept behind the treatment system is easy to explain. It is believed that additional buy- in for the process will be achieved when the citrus growers have an opportunity to see the treatment system "in action" . A modified aquatic plant system has also been discussed as a primary functional element of stormwater parks that may be located nearer to or within the urban area of the IRFWCD . The proposed project will allow the basic operation of a managed aquatic plant system to be observed, to be sure that certain operations, particularly biomass removal through harvesting, can be accomplished in a park setting. The ATSTM ' s benefits include a high level of nutrient (nitrogen and phosphorus) and suspended solids removal efficiency, very efficient utilization of the existing County-owned site, production of a useful by-product, wetland and wildlife habitat creation, continuous removal of large amounts of pollutants, and color removal . Monitoring A monitoring program will be conducted as part of this project. There is some existing data that will be verified by pre-construction monitoring of flows in the canal . Parameters that will be measured will include the following : • pH , • dissolved oxygen, • salinity, • temperature, • Total Kjeldahl Nitrogen, • ammonia, • nitrates and nitrites, • total phosphorous, • ortho-phosphorous, • total organic carbon (TOC) , • color, • biochemical oxygen demand (BOD), • total suspended solids, • alkalinity, and • pesticide and heavy metal scans (limited) . Following construction of the treatment system, each process will be monitored for the above parameters to determine the removal efficiency of each process, and pollutant load reduction level for the entire managed aquatic plant stormwater treatment system. DEP Agreement No. G0143 , Attachment A, Page 7 of 9