Where’s My Material? Appropriate Planning for Cap and Habitat Restoration Material Quantities Presented by Paul LaRosa, P.E., John Verduin, P.E., and Ram Mohan, P.E., Ph.D. October 25, 2012

Outline Importance of Estimating Material Volumes Review of Factors Affecting Material Volumes Case Study – St. Lawrence River Summary of Recommendations

Importance of Estimating Material Volumes Aids in development of engineer’s accurate estimates Provides tool to evaluate bids and minimize potential for cost overruns Allows for appropriate planning for post- construction elevations –e.g., accounting for over-placement, “run-out,” etc.

Factors Affecting Material Volumes Project and contractual requirements Materials handling and placement Material type and gradation Site-specific factors

Project and Contractual Requirements Over-placement allowances Over-placement allowance Armor Layer (Gravel) Isolation Layer (Sand) 12” Minimum, plus over-placement Over-placement allowance 6” Minimum

Project and Contractual Requirements Cap side slopes (i.e., “run-out”) Run-outArea to be capped SEDIMENT TO BE CAPPED Sand cap material Habitat layer Gravel cap armor material

Materials Handling and Placement Management of stockpile Placement beyond the required limits or grades based on equipment configuration Uniformity of placement

Source: Source: Terra et Aqua (No.122/March 2011 Broadcast Spreader Hydraulic Slurry Materials Handling and Placement Conveyor Belt Mechanical Bucket Source: Putzmeister.com

Materials Handling and Placement Placement beyond the required limits or grades based on equipment configuration

Uniformity of Placement Materials Handling and Placement

Material Type and Gradation Relative density of materials in place compared to stockpile Loss to water column via suspension and transport Mixing with underlying sediment Source:

Sand Native Material Habitat Layer – Filling Interstitial Space Site-Specific Factors Water depth Currents and tides Bottom slope and “roughness”

Case Study – St. Lawrence River

Summary of Recommendations Typical Excess Material Factors Based on Anchor QEA Experience Source of Excess Material Percent of Total Material Volume (Typical) Material handling<0.5 Loss to water column through turbidity30-50 percent of fines* Mixing with underlying sediment Site specific (minimal ) Compaction of sand in water compared to stockpile15-20 Run out (based on cap height)1-5 Volume above "target" cap thickness (over-placement)20-30 Overlap in capping lanes (for slurry or broadcast spreaders) 5-10 Excess from equipment0.5-5 Localized repairs0.5-2 * Water column loss factor based on fines content (% passing No. 200 sieve) of cap material

Summary of Recommendations Ways to Control Excess Materials Pilot studies Operational modifications Quality assurance/quality control (QA/QC) Regular tracking of material volume Adaptive management

Questions? Paul LaRosa, P.E. Anchor QEA, LLC Source: