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### INITIAL REVIEW EXPOSURE REPORT (IRExR)
Chemical ID: P-13-0288 Reviewer: Kwon/SD

Results Table: Dose, Concentration, and Days Exceeded Results Summary

Exposure Scenario 1 Water Landfill Stack Air Fugitive Air
Drinking Water Fish Ingestion ADR LADD ADR LADD 7Q10 4 CC = 1 PDM Days Exceede d LADD ADR LADD ADR LADD

Release activity(ies) 2 ; exposure calculation(s) 3 mg/kg/day mg/kg/day mg/kg/day mg/kg/day μg/l # Days mg/kg/day mg/kg/day mg/kg/day mg/kg/day mg/kg/day

M a x ADR: max acute eco 3.20E-04 --- 3 .59E-04 --- 5.66E+00 --- --- --- --- 1.10E-01 ---

M a x LADD --- 1.59E-07 --- 1.10E-07 --- --- --- --- --- --- ---

1 Exposure scenario titles consist of release activity followed by exposure calculation abbreviation. 2 Release activities are from engineering report's Manufact uring (Mfg), Processing (Proc) and Use release activity labels. Multiple release activities are combined in one exposu re scenario if their releases occur at same location. 3 Exposure calculations are Acute Dose Rate (ADR), Lifetime Average Daily Dose (LADD), and Probabilistic Dilution Model (PDM). There may be one, two, or all th ree exposure calculations per exposure scenario. CC is the aquatic concentration of concern. 4 This column displays concentration values for the 7Q10 streamflow, which is defined as the average daily streamflow of the seven consecutive days of lowest flow within a ten year period.
Remarks:3/13/2013 Page 2 of 7

INITIAL REVIEW EXPOSURE REPORT

Chemical ID: P-13-0288 Assessor: Kwon/SD
ENVIRONMENTAL RELEASES
Scenario#:1 Number of Release Sites: Release Activity: Max ADR Release Description: WATER LANDFILL Non-sludge/Sludge STACK FUGITIVE

Total Releases: (kg/yr) (kg/yr) (kg/yr) (kg/yr)

Non-sludge/Sludge Release Days/yr:
Per Site Release: (kg/site/day) (kg/site/day) (kg/site/day) (kg/site/day)

Remarks:3/13/2013 Page 3 of 7

INITIAL REVIEW EX POSURE REPORT
Chemical ID: P-13-0288 SITE-SPECIFIC HUMAN AND AQUATIC EXPOSURES TO SURFACE WATER RELEASES
SCENARIO NUMBER:1 RELEASE ACTI VITY: Max ADR FACILITY NAME: FACILITY LOCATION: RECEIVING WATER NAME: REACH NUMBER: FACILITY ON REACH: DISCHARGE TYPE: NPDES PERMIT #: EXPOSED POPULATION: Adult

WWT REMOVAL (%) RELEASE DAYS PRETREATMENT RELEASE (kg/site/day) POSTTREATMENT RELEASE (kg/site/day) DWT (%) BCF (L/kg) 0.00 161.00

AQUATIC EXPOSURE ESTIMATES - SURFACE WATER FLOW DESCRIPTOR Harmonic Mean 30Q5 7Q10 1Q10 PLANT FLOW (MLD) CONCENTRATION ( μ g/L) 1.24 3.82 5.66 6.97 NA

DRINKING WATER INGESTION AND FISH INGESTION EXPOSURE ESTIMATES

Exposure Units Drinking Water Results Drinking Water Units Fish Ingestion Results Fish Ingestion Units
Cancer
LADD pot 1.59E-07 mg/kg/day 1.10E-07 mg/kg/day
LADC pot 8.17E-06 mg/L 1.31E-03 mg/kg
Acute
ADR pot 3.20E-04 mg/kg/day 3.59E-04 mg/kg/day

Surface Water Comments:3/13/2013 Page 4 of 7

INITIAL REVIEW EX POSURE REPORT Chemical ID: P-13-0288
INHALATION EXPOSURE ESTIMATES (POST-TREATMENT)
SCENARIO #: 1 RELEASE ACTIVITY: Max ADR RELEASE DESCRIPTION: METHOD OF CALCULATION: Screen3 EXPOSED POPULATION: Adult

Number of Sites: Per Site Fugitive Release: kg/site/day Fugitive Release Days per Year: days % Removal via Fugitive Release: % Total Fugitive Release: kg/yr Max Annual Average Air Concentration (Fugitive): 0.79 μg/m 3

Max 24 Hour Average Air Concentration(Fugitive): 600.00 μg/m 3

Per Site Stack Release: kg/site/day Stack Release Days per Year: days % Removal via Stack Release: % Total Stack Release: kg/yr Max Annual Average Air Con centration (Stack): 0.00 μg/m 3 Max 24 Hour Average Air Concentration (Stack): 0.00 μg/m 3

ASSUMPTIONS Exposure Units Results (Stack) Results (Fugitive) ED (years) AT (years) BW (kg) Inh. Rate (m 3 /hr) Cancer LADD pot (mg/kg/day) N/A 5.82E-05 30.00 75.00 71.80 0.55 LADC pot (mg/m 3 ) N/A 3.16E-04 30.00 75.00 NA NA Acute ADR pot

(mg/kg/day) N/A 0.11 NA 1 day 71.80 0.55

Inhalation Comments:3/13/2013 Page 5 of 7

Stack Parameter Data Fugitive Parameter Data Stack Height 10.00 Release Height: 3.00 m Inside Stack Diameter: 0.10 Length of Release Opening: 10.00 m

Stack Gas Exit Velocity: 0.10 Width of Release Opening: 10.00 m

Stack Gas Temperature: 293.00

Meteorological and Terrain Information:
Surrounding Land Use: Rural Terrain Height: 0.00 m Distance to Residence of Interest: 100.00 m Meteorological Class: Full Stability Class: NA Wind Speed: NA

Downwash Information:
Facility Length: NA m Facility Width: NA m Facility Height: NA m3/13/2013 Page 6 of 7

INITIAL REVIEW EXPOSURE REPORT

Chemical ID: P-13-0288 Assessor: Kwon/SD
ENVIRONMENTAL RELEASES
Scenario#:2 Number of Release Sites: Release Activity: Max LADD Release Description: WATER LANDFILL Non-sludge/Sludge STACK FUGITIVE

Total Releases: (kg/yr) (kg/yr) (kg/yr) (kg/yr)

Non-sludge/Sludge Release Days/yr:
Per Site Release: (kg/site/day) (kg/site/day) (kg/site/day) (kg/site/day)

Remarks:3/13/2013 Page 7 of 7

INITIAL REVIEW EX POSURE REPORT
Chemical ID: P-13-0288 SITE-SPECIFIC HUMAN AND AQUATIC EXPOSURES TO SURFACE WATER RELEASES
SCENARIO NUMBER:2 RELEASE ACTI VITY: Max LADD FACILITY NAME: FACILITY LOCATION: RECEIVING WATER NAME: REACH NUMBER: FACILITY ON REACH: DISCHARGE TYPE: NPDES PERMIT #: EXPOSED POPULATION: Adult

WWT REMOVAL (%) RELEASE DAYS PRETREATMENT RELEASE (kg/site/day) POSTTREATMENT RELEASE (kg/site/day) DWT (%) BCF (L/kg) 0.00 161.00

AQUATIC EXPOSURE ESTIMATES - SURFACE WATER FLOW DESCRIPTOR Harmonic Mean 30Q5 7Q10 1Q10 PLANT FLOW (MLD) CONCENTRATION ( μ g/L) N/A N/A N/A N/A NA

DRINKING WATER INGESTION AND FISH INGESTION EXPOSURE ESTIMATES

Exposure Units Drinking Water Results Drinking Water Units Fish Ingestion Results Fish Ingestion Units
Cancer
LADD pot 1.59E-07 mg/kg/day 1.10E-07 mg/kg/day
LADC pot 8.17E-06 mg/L 1.31E-03 mg/kg
Acute
ADR pot N/A mg/kg/day N/A mg/kg/day

Surface Water Comments: