COMPREHENSIVE UNDERSTANDING OF EMISSIONS AND CONTROL MEASURES PROVIDE PROTECTIVENESS TO POTENTIAL RECEPTORS

Donald Carpenter

Thomas Fischer

Brian Magee

Robert Ferree

Jing Gabriel

PROJECT LOCATION HAS IMPORTANT REMEDIAL IMPLICATIONSSEVERE COLD AND HEATRECORD HIGH 115° FRECORD LOW -46° FLARGEST TEMPERATURE EXTREME ON EARTH – per The Weather ChannelSEVERE THUNDERSTORMS AND HIGH WINDSLimited Construction Season

High Required Production Rates

Hot and Windy

CLOSE PROXIMITY OF RESIDENCES EMPHASIZES IMPORTANCE OF UNDERSTANDING EMISSIONS

200 meters

SIGNIFICANT COAL TAR WASTES ARE KNOWN TO BE PRESENT

BENZENE 76 ppm (most significant toxicant)NAPHTHALENE 1,500 ppm (most significant malodorant)PHENANTHRENE 400 ppm (potential toxicant)

Preliminary off-gas emissions “bounding case” modeling suggested exceedances of applicable occupational standards at “reasonable” production rates

Inspired interest in a trial excavation to determine emissions potential

THE INVENTORY OF OFF-GAS EMISSION SOURCES MUST BE ACCURATELY SIMULATED

Primary Excavation

Stockpiled Material

Loading into Highway Trucks

TRIAL EXCAVATION FOLLOWED A PROVEN APPROACH

Atmospheric conditions

Concentration of Contaminant

(Soil)

Mass of Soil Disturbed per Unit

TimeDegree of

Disturbance

Concentration of Off-Gas Downwind

Backmodeling allows estimate as to the “RELEASE FRACTION”

MULTIPLE SUMMA CANISTERS PROVIDE DATA FOR ENTIRE INVENTORY OF EMISSIONS

Canisters #1 and #5 – Continuous (50 minute samples)

Canister #2 – Active Excavation (10 minute sample)

Canister #3 – Passive Emission (30 minute)

Canister #4 – Secondary Handling (10 minute)

WORST CASE MODELING DEMONSTRATES SHORT TERM PROTECTIVENESS TO THE COMMUNITY

580 ug/M3

MODELING RESULTS DEMONSTRATE LONG TERM PROTECTIVENESS TO THE COMMUNITY

4.5 ug/M3

NUISANCE ODORS WOULD BE LARGELY CONFINED TO THE SITE

SYSTEMATIC ANALYSIS OF CONTROL MEASURES CAN PROVIDE INSIGHT INTO PROTECTIVENESS

LINEAR DECREASE IN CONCENTRATIONS IS FOUND RELATIVE TO PERCENT SUPPRESSION

0% 20% 40% 60% 80% 90%0

100

200

300

400

500

600Relationship Between Estimated Concentration and Percent Relative Off Gas Suppression

Concentration

Percent Relative Off Gas Suppression

EFFICACY OF A SPRUNG STRUCTURE IS LIMITED BY EFFECTS OF AN ACCIDENTAL RELEASE

PUBLIC EXPOSURE CONCENTRATION DURING ACCIDENTAL RELEASE (g/m3) - 5 MINUTE DURATION

CONCENTRATION WITHIN CONFINING STRUCTURE (g/m3)

VENTILATION RATE OF AIR TREATMENT SYSTEM (acfm)

LIMITING FACTOR

3,200 54,000 18,000 3,200 g/m3 (5 min) Exposure Limit

16,000 250,000 3,600 16,000 g/m3 (5 min) Exposure Limit

18,000 283,000 3,200 580 g/m3 Short Term Exposure Limit During Routine Ops (1 hr) and Limit for Level C PPE

COMPREHENSIVE UNDERSTANDING OF EMISSIONS AND CONTROL MEASURES PROVIDE PROTECTIVENESS TO POTENTIAL RECEPTORSTHE INVENTORY OF OFF-GAS EMISSION SOURCES MUST BE ACCURATELY SIMULATED

MULTIPLE SUMMA CANISTERS PROVIDE DATA FOR ENTIRE INVENTORY OF EMISSIONS

WORST CASE MODELING DEMONSTRATES SHORT TERM PROTECTIVENESS TO THE COMMUNITY

MODELING RESULTS DEMONSTRATE LONG TERM PROTECTIVENESS TO THE COMMUNITY

NUISANCE ODORS WOULD BE LARGELY CONFINED TO THE SITE

LINEAR DECREASE IN CONCENTRATIONS IS FOUND RELATIVE TO PERCENT SUPPRESSION

EFFICACY OF A SPRUNG STRUCTURE IS LIMITED BY EFFECTS OF AN ACCIDENTAL RELEASE