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### INITIAL REVIEW EXPOSURE REPORT (IRExR) Chemical ID: P-13-0839 Reviewer: Wong/BC

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 m g/kg/day mg/kg/day mg/kg/day μg/l # Days mg/kg/day m g/kg/day mg/kg/day mg/kg/day mg/kg/day

USE: Max LADD --- --- --- --- --- --- 9.24E-04 --- 5 .41E-04 --- ---

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 three 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:9/4/2013 Page 2 of 5

INITIAL REVIEW EXPOSURE REPORT

Chemical ID: P-13-0839 Assessor: Wong/BC
ENVIRONMENTAL RELEASES
Scenario#:1 Number of Release Sites: Release Activity: USE: Max LADD Release Description: WATER LANDFILL Non-sludge/Sludge STACK FUGITIVE

Total Releases: (k g/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)

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INITIAL REVIEW EX POSURE REPORT Chemical ID: P-13-0839

DRINKING WATER EXPOSURE ESTIMATES FROM LANDFILL RELEASES
SCENARIO #: 1 ACTIVITY: USE: Max LADD
RELEASE DESCRIPTION: EXPOSED POPULATION: Adult

NUMBER OF SITES NON-SLUDGE LANDFILL RELEASE AND DAYS OF RELEASE (kg/site/day)/(days) LANDFILLED SLUDGE 1 AND DAYS OF RELEASE (kg/site/day)/(days) MIGRATION DESCRIPTOR 2 ADSORPTION TO WASTEWATER SLUDGE (%) DRINKING WATER TREATMENT (%)

0.00 0.00

1 Landfilled sludge equals the fraction adsorbed to wastewater treatment sludge times the surface water pre-treatment release.

2 Migration Descriptor Log Koc Groundwater Concentration (GWC) (mg/L per kg release) Negl igible no migration None Negligible to slow > 4.5 3.21E-6 Slow <4. 5 to 3.5 2.67E-5 Moderate <3.5 to 2.5 5.95E-5 Rapid <2. 5 7. 55E-5

ASSUMPTIONS Exposure Units Results ED (years) AT (years) BW (kg) IR (L/day) Cancer LADD pot (mg/kg/day) 9.24E-04 30.00 75.00 71.80 1.40 LADC pot (mg/L) 4.74E-02 30.00 75.00 NA NA

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INITIAL REVIEW EX POSURE REPORT Chemical ID: P-13-0839
INHALATION EXPOSURE ESTIMATES (POST-TREATMENT)
SCENARIO #: 1 RELEASE ACTIVITY:USE: Max LADD
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): 0.00 μg/ m 3

Max 24 Hour Average Air Concentration(Fugitive): N/A 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): 7.35 μg/m 3 Max 24 Hour Average Air Concentration (Stack): N/A 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) 5.41E-04 N/A 30.00 75.00 71.80 0.55
LADC pot (mg/m 3 ) 2.94E-03 N/ A 30.00 75.00 NA NA
Acute
ADR pot

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

Inhalation Comments:9/4/2013 Page 5 of 5

Stack Parameter Data Fugitive Parameter Data Stack Height 10.00 m Release Height: N/A
Inside Stack Diameter: 0.10 m Length of Release Opening: N/A

Stack Gas Exit Velocity: 0.10 m /sec Width of Release Opening: N/A

Stack Gas Temperature: 293.00 K

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

Do wnwash Information:
Facility Length: NA m Facility Width: NA m Facility Height: NA m