Apr 27 2004
ProTech General Contracting Services Inc., a water treatment company specializing in stormwater control, today announced that it has successfully demonstrated its polymer coagulation/flocculation system for runoff and stormwater clarification at several large-scale project sites. The polymer coagulation/flocculation units were a key component in the stormwater treatment systems employed at several construction sites in California’s Central Valley, including sites of several thousand acres requiring multiple 1000 gallon per minute systems.
“Construction site runoff and stormwater is increasingly subject to stricter discharge water quality standards,” says Len Pisciotta, President of ProTech. “Today the only practical way for many projects to meet permit requirements is by using an active technology to improve sediment removal efficiency and, consequently, water quality. ProTech’s water clarification systems incorporate a coagulation process that vastly improves sediment removal efficiency. The results are higher flow rates, smaller holding basin volumes, and improved water quality – all at lower cost.”
Many construction projects, particularly those where runoff contains fine-grained sediment that is impractical to remove by simple gravity sedimentation or filtration, are finding that the only way to meet permit requirements is to incorporate some type of active treatment process in their water management system. Polymer-based coagulation systems are among the most efficient and cost-effective methods available. Although polymer clarification has been used for many years for industrial and other applications, it has only recently been used in the mobile, temporary treatment systems required at construction sites. ProTech’s water treatment systems are designed to meet site specific flow requirements and discharge permit criteria, and typically include clarifier tanks, sand filters, bag or cartridge filters, as well as the polymer coagulation system. Systems are also equipped with automated turbidity meters with chart recorders, overflow sensors, automatic flow control switches, or pressure sensors linked to cellular devices for remote monitoring and operation. During the rainy season of winter 2003/2004, ProTech installed and operated several stormwater clarification systems utilizing polymer coagulation/flocculation.
As an example, at the Lincoln Crossing 1000-acre planned community in California’s Central Valley, ProTech installed and operated a 1000 gallon per minute system to treat runoff that contained high levels of fine-grained, colloidal material and iron oxides. Runoff at the project was often very turbid, with measured turbidities commonly over 1,000 NTU (Nephelometric Turbidity Units). Discharge from the site led to surface waters that support steelhead trout, which are listed as threatened species under the Endangered Species Act. Consequently, maintaining water quality was a high priority at the project. Because the colloidal material did not settle and was difficult to remove, a ProTech polymer coagulation/flocculation was incorporated in the water treatment system design.
“To meet our discharge permit requirements, we needed a temporary water treatment system to treat site runoff,” says Ed Horn, Construction Manager, SunCal Companies. “We looked at several alternatives, and found that ProTech’s water treatment system met our water quality criteria. ProTech incorporates the latest filtration technology, and meets Best Management Practices and Best Available Technologies standards of the California Regional Water Quality Control Board. Several storms occurred during the winter rainy season, including one with two inches of rain in six hours. The treatment system operated flawlessly. Discharge never exceeded 50 NTU, although influent was over 1,000 NTU.”
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