ffd case study

S 2 C2 inc.

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Streamlined Site Characterization and Closure

Fuel Fluorescence Detector (FFD) Case StudyDelineating residual and free-phase diesel impacts in

soil from delineation to engineering design

Prepared By: S2C2 inc.

S2 C2 inc.

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Fuel Fluorescence Detector (FFD)

Dual Downhole FFD detects the fluorescence produced by aromatic hydrocarbons when excited by an ultraviolet (UV) light source.

The FFD probe is coupled with Cone

Penetrometer Technology (CPT) which gives a simultaneous read-out of lithology.

Continuous, real-time data generated

during the push allows for rapid delineation of Light Non-Aqueous Phase Liquids (LNAPLs) in the subsurface.

S2 C2 inc. Example FFD Log

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S2 C2 inc.

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Project Summary

Initial Characterization

• Minor CVOC impacts and free-phase diesel detected in a number of wells • Limited characterization of actual soil impacts at former UST location.

Objective:• Complete delineation of #2 diesel impacts at former UST location to allow for

detailed development of remediation bid specs.

S2 C2 inc.Project Summary

Diesel impacted soil was initially delineated using the FFD in 3 days.

Depth discrete soil intervals were identified based on logs to collect collaborative data to evaluate relationship of FFD response to DRO analytical results.

Collaborative data were evaluated using a “bin” analysis to determine a conservative FFD threshold value where soil would likely be over or under soil applicable cleanup criteria, with statistical certainty.

Following collaborative FFD/DRO evaluation, in-situ post excavation samples were collected based on the model results.

Data visualization was completed to aid in preparing detailed bid specs for soil excavation.

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S2 C2 inc.Implemented Dynamic Work Strategy

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S2 C2 inc.Collect Collaborative Data

Identified 8 Soil Borings over a range of FFD responses.

Collected discrete soil samples using Geoprobe’s ® 3.25-inch dual tube.

Collected In-Situ Post-Ex samples based on this analysis and FFD model.

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S2 C2 inc.Integrated Real-Time Data into Engineering Estimates

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S2 C2 inc.

Project Results

Delineation completed in five days over a two week period• 3 days of FFD• 1 day of correlation sampling• 1 day of in-situ post excavation sampling

Data visualization incorporated into consultants bid specs for dewatering, sheet pile wall and soil excavation

Soil volumes were estimated based on FFD model results Post Excavation samples were collected prior to excavation Remediation was completed in timely manner with no significant

change orders. Estimated cost saving from using FFD and dynamic work strategy -

$250,000.

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ffd case study

Documents

site characterization

soil excavation

ffd probe

collaborative data

relationship of ffd

closureexample ffd log

diesel impacts

realtime data