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Silt Stop ®

Description

Silt Stop ® is an anionic polymer focculent that is used with Filtrexx ® sediment control and fltration practices, such as Sediment control, Check dams, Concrete washouts, Slope interruption, and Filtration system baffes. It is specifcally used to further

reduce suspended solids and turbidity in storm runoff . Silt Stop ® should not be used without one of these practices and should not be applied within 25 ft (7.6m) of natural waterways (KY TC, 2006). When using Silt Stop ® there should be a secondary sediment control or fltration practice installed after the practice where it is applied, as this product should not be directly discharged into storm inlets, drains, natural receiving waters, or wetlands. For optimum performance this Support Practice tm should be applied immediately upslope and/or along the inner circumference of the Filtrexx ® practice.

Function

Silt Stop ® is an anionic, polymer focculent that reduces suspended solids and turbidity when applied with Sediment control, Check dams, Concrete washouts, Slope interruption, and Filtration system baffes. Silt Stop ® is a material that focculates negatively charged eroded soil colloids together to form larger aggregates (or focs) that reduce their propensity to be transported by sheet runoff. Silt Stop ® is anionic, which means it has a positive electrostatic charge that attracts negatively charged clay colloids. As soil colloids foc together to form a larger mass and weight they eventually fall out from storm runoff, settle in retained runoff, and are more diffcult to transport in sheet fows.

Additionally, focculants can create a surface coagulant which buffers the mobility of soil

particulates, reducing their transportability in storm runoff. Due to the coagulation characteristic this product may reduce hydraulic fow through rate and permittivity of the Filtrexx ® practices listed above. For optimum performance, site soil samples should be taken and sent to Applied Polymer Systems to determine the best Silt Stop ® product for your soil type. For more information on testing and research with Silt Stop ® and Filtrexx ® products see research summaries in the Appendix.

Installation

1. Where required, Silt Stop ® shall be surface applied manually, directly upslope, and along the entire length of the Filtrexx ® sediment control or fltration practice.

2. Silt Stop ® shall be applied at a rate of 100 grams per linear ft (0.3 m)

3. Silt Stop ® shall not be applied within 25 ft (7.6 m) of receiving stream, river, lake, or wetland.

Inspection & Maintenance

1. Additional applications of Silt Stop ® may be added after storm events to decrease suspended solids and turbidity resulting from future rainfall/ runoff events.

2. If Sediment control, Check dams, Concrete washouts, Slope interruption, or Filtration system baffes exhibit signifcantly reduced hydraulic fow through rates or become clogged, they should be cleaned out or replaced.

Method of Measurement

Bid items shall show measurement as APS Silt Stop tm

+ Filtrexx ® BMP per linear ft or per linear m installed.

Section 3: Support Practices ™

Silt Stop ® Polymer

Sediment Reduction Technology