1 / 20

BoRit Asbestos Superfund Site

BoRit Asbestos Superfund Site. Remedial Overview of USACE Reservoir Report January 15, 2014 Jill Lowe, EPA Travis Fatzinger, USACE. BoRit Asbestos Superfund Site Overview. USACE Report on BoRit Reservoir Reservoir Hydrology Berm Stability Options Reviewed.

wesley
Download Presentation

BoRit Asbestos Superfund Site

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BoRit Asbestos Superfund Site Remedial Overview of USACE Reservoir Report January 15, 2014 Jill Lowe, EPA Travis Fatzinger, USACE

  2. BoRit Asbestos Superfund SiteOverview • USACE Report on BoRit Reservoir • Reservoir Hydrology • Berm Stability • Options Reviewed

  3. BoRit Asbestos Superfund SiteUSACE Report • Remedial Inter Agency Agreement (IA) with U.S. Army Corps of Engineers (USACE) • Tasks • Analyze Hydraulics of Reservoir • Assess Berm Stability • Investigations Performed • Geotechnical Investigations • Water Level Investigation • Berm slope stability and seepage

  4. BoRit Asbestos Superfund SiteUSACE Report • Hydraulics Study • Transducers – March-August 2013 • 3 transducers in wells MW-01a, MW-02, and MW-03 • 1 in Reservoir • Transducer – July 2013-August 2013 • 1 transducer in background well, MW-07

  5. Legend Monitoring Well, Transducer Monitoring Well, No Transducer Staff Gauge, Transducer Staff Gauge, No Transducer Pennsylvania BoRit Figure 3.1 Monitoring Locations BoRit Asbestos Superfund Site Ambler, PA August 2013

  6. BoRit Asbestos Superfund SiteUSACE Report • Hydraulics Study Conclusions • Reservoir • No direct correlation between groundwater and Reservoir • Water levels correlate to rainfall and evaporation • Known seep is not significant • Groundwater • Significant drawdown Monday through Friday • Identified 2-Non-potable production wells

  7. BoRit Asbestos Superfund SiteUSACE Report

  8. Geophysical Investigation • Multi-channel analysis of surface waves (MASW) • Characterize Soil • Self-potential (SP) • Water flow • EM61 Metal Detector • Ground Penetrating Radar (GPR) • Probable pipe locations targeted based upon drawings from Whitpain Township and removal work • Known pipes likely filled in with sedimentation

  9. Figure 2.2 Zone of Weak Material in SW Berm BoRit Asbestos Superfund Site Ambler, PA August 2013

  10. Geotechnical Investigation • Boring locations based on survey cross-sections, geophysical results, and seepage locations • Three Borings • Continuous Split Spoon Sampling • Advanced until bedrock refusal • Lab testing on Samples • Included sieve analyses, triaxial consolidated- undrained, unconfined compression

  11. Figure 2.4 Locations of BOB-1, BOB-2, and BOB-3 BoRit Asbestos Superfund Site Ambler, PA August 2013

  12. Slope Stability Model • GeoStudio 2012 • Seep /W • Slope /W • Survey Profiles • Soil Profiles • Lab Results

  13. Legend FS= 0.93 Pennsylvania BoRit Figure 4.5 BOB-2 Current Geometry High Head BoRit Asbestos Superfund Site Ambler, PA August 2013

  14. Current ConditionSlope Stability Results

  15. BoRit Asbestos Superfund SiteUSACE Report • USACE Options to cover ACM and stabilize berm • Option 1 • Flatten exterior slope • Add stability berm to exterior toe of slope (Wissahickon side) • Option 2 • Sheetpile • Option 3 • Increase berm’s cross-sectional width • Flatten interior slope to 3H:1V =18° • Material stable to 30° resulting in Factor of Safety of 1.7

  16. Legend FS= 1.63 Pennsylvania BoRit Figure 4.8 BOB-2 Proposed Geometry Normal Head BoRit Asbestos Superfund Site Ambler, PA August 2013

  17. Proposed GeometrySlope Stability Results

  18. Option 3 with GCL • Supplement clay fill with Geosynthetic Clay Liner (GCL) • GCL consists of bentonite between layers of Geotextile • “Self Healing” Properties • Benefits • Reduced berm width • Homogenous, uniform installation • Less fill and haul trucks required • Sand and Clay fill geotechnical properties testing complete • GCL FS for Bob-2 Normal head conditions 1.50, High head 1.41

  19. GCL/ Backfill placement • Backfill material Sandy Lean Clay • Clay material placed on inside slope compacted in lifts to 90% standard Proctor • GCL placed on top- then covered by 2-3 ft additional compacted clay • Existing berm will be dry and compacted from additional weight

  20. Legend FS= 1.500 Pennsylvania BoRit BOB-2 GCL Normal Head BoRit Asbestos Superfund Site Ambler, PA January 2014

More Related