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Page 2 PC South — Approval of Contract for Construction BCC Meeting — July 16, 2013 July 8, 2013 E. Consider payment of a Technology License Fee to Hydromentia, Inc. for use of proprietary Algal Turf Scrubber technology at PC South. PC South will be a regional stormwater pollution reduction facility similar to Egret Marsh Stormwater Park (Egret Marsh), in that it uses algae to remove dissolved nutrients from water. The treatment facility will be located adjacent to the South County Water Treatment Plant on a former orange grove site. A large pump station to be constructed within the Indian River Farms Water Control District (IRFWCD) South Relief Canal will pump up to 10 million gallons per day (MGD) of canal water onto a concrete floway on which algae will be grown. At the floway influent structure, up to 1.5 MGD of brine concentrate from the South County Reverse Osmosis (RO) Water Treatment Facility will be blended with the canal water. The mixture will travel down the floway surface where algae will remove dissolved nitrogen and phosphorus and reduce some trace elements. Additionally, the brine concentrate's dissolved hydrogen sulfide will be released into the atmosphere. After passing through the algae crop, the water will flow into a polishing pond and a wetland system for final pollutant reduction, pH stabilization, and temperature equalization. The treated effluent will then flow back to the South Relief Canal and eventually into the Indian River Lagoon. The algae's ability to remove organic pollutants from the brine concentrate and reduce the brine toxicity to marine organisms, will allow the County Division of Utility Services to comply with a Florida Department of Environmental Protection (FDEP) Consent Order. The Consent Order requires the County to remove its current brine concentrate direct discharge from the South Relief Canal or face regulatory fines. Project construction timing is critical because of the Consent Order. County Utilities will request that FDEP grant a Consent Order time extension once the project schedule becomes finalized. The Consent Order expires on October 22, 2013. The 12.8 acre PC South site is smaller than the 35 acre Egret Marsh facility and space is not available for processing algae products. Therefore, all algae harvested at PC South will be transported to Egret Marsh and mixed with Egret Marsh's harvested algae for processing into reusable compost or other environmentally friendly byproducts. Processing harvested algae at a single facility will maximize efficiency and reduce overall processing costs. The floway length and width was based on a pilot plant study performed on the canal water/RO brine concentrate. Based on removal rates experienced during the pilot plant study, the proposed facility is expected to remove the following quantities of nutrients from the mixture each year: • Total Nitrogen = 9,830 pounds = 2,458 forty pound bags of 10-5-10 (N -P -K) fertilizer. 2 F:\Public Works\KeithM\Stormwater Projects\PC South Construction\Agenda Items\Agenda - PC South Recommendation of Bid 17 8 Award for Construction.doc