Versatility of “Vacuum Bag Dewatering ”(pat pend) of Dredged Organic Silt Roger G. Miller, P.E., President Miller Engineers & Scientists Sheboygan, Wisconsin, USA

Geotube® Gravity Dewatering

Organic Silt after three months in Geotube® Moisture Content = *120% Liquid Limit = *140% Plasticity Index = *80% Percent Sand and Gravel = *35% Su/Pp ~ 0.5 *Dry Wt Basis

Vacuum Bag Prototype Test (2008) Clear Water Discharge

Vacuum Bag System

Mechanical Filter Plate Presses, LFR 2009

Sediment “Cake” after Dewatering

Drainage Layer Thickness vs. Time Organic Silt Layer Thickness Feet (m) Time To Consolidate (Days) 1 (0.3) 2 ½ 2 (0.6) 10 3 (0.9) 23 4 (1.2) 41 Time for dewatering is proportional to the square of the height of the material. Temperature vs. Time Material Temperature Degrees F 34 50 59 68 77 86 95 104 113 (Degrees C) (5) (10) (15) (20) (25) (30) (35) (40) (45) Time Adjustment Factor 1.52 1.31 1.14 1.00 0.89 0.80 0.72 0.65 0.60 Increasing material temperature shortens consolidation time by lowering the viscosity of the pore water.

Vacuum Bag Consolidation of Geotubes®

Vacuum Bag Dewatering in Barge

Vacuum Bag Dewatering of Sedimentation Basin

Reef Building or Deep Water Disposal

Sediment Vacuum Bag Dewatering in the Lab

Contact Information: Roger G. Miller, PE, President Miller Engineers & Scientists 5308 South 12th Street Sheboygan, WI 53081 Phone (800) 969-7013 US Patent 7,454,847 B1 issued and general concept patent pending.