Appendix 9 – Environmental Risk Screen 
Table 1 – PB-HAP Benchmarks Included in the Environmental Risk Screen 

EcoHAP Assessment Endpoint Benchmark Effects Level Benchmark Value

Benchmark 

Source

Tier 1 Eco 

Screening 

Threshold 

(TPY)

Cadmium Fish - Avian Piscivores NOAEL (merganser) 0.7 (mg/kg BW/day) d 2.03E-01

Cadmium Fish - Avian Piscivores LOAEL (merganser) 1 (mg/kg BW/day) d 2.90E-01

Cadmium Fish - Mammalian Piscivores NOAEL (mink) 0.742 (mg/kg BW/day) e 4.06E-01

Cadmium Fish - Mammalian Piscivores LOAEL (mink) 7.42 (mg/kg BW/day) e 4.06E+00

Cadmium Sediment Community No-effect Level 0.6 (mg/kg dry wt) b 1.73E+00

Cadmium Sediment Community Threshold Level 1.2 (mg/kg dry wt) a 3.45E+00

Cadmium Sediment Community Probable-effect Level 3.5 (mg/kg dry wt) b 1.01E+01

Cadmium Surface Soil - Dist. 1 - 312 m Threshold - Mammalian Insectivores (shrew) 0.36 (mg/kg dry wt) a 3.64E-01

Cadmium Surface Soil - Dist. 1 - 312 m Threshold - Avian Ground Insectivores (woodcock) 0.77 (mg/kg dry wt) a 7.79E-01

Cadmium Surface Soil - Dist. 1 - 312 m Threshold Level - Plant Community 32 (mg/kg dry wt) a 3.24E+01

Cadmium Surface Soil - Dist. 1 - 312 m Threshold Level - Invertebrate Community 140 (mg/kg dry wt) a 1.42E+02

Cadmium Surface Soil - Dist. 2 - 850 m Threshold - Mammalian Insectivores (shrew) 0.36 (mg/kg dry wt) a 5.21E-01

Cadmium Surface Soil - Dist. 2 - 850 m Threshold - Avian Ground Insectivores (woodcock) 0.77 (mg/kg dry wt) a 1.11E+00

Cadmium Surface Soil - Dist. 2 - 850 m Threshold Level - Plant Community 32 (mg/kg dry wt) a 4.63E+01

Cadmium Surface Soil - Dist. 2 - 850 m Threshold Level - Invertebrate Community 140 (mg/kg dry wt) a 2.03E+02

Cadmium Surface Soil - Dist. 3 - 1,500 m Threshold - Mammalian Insectivores (shrew) 0.36 (mg/kg dry wt) a 7.53E-01

Cadmium Surface Soil - Dist. 3 - 1,500 m Threshold - Avian Ground Insectivores (woodcock) 0.77 (mg/kg dry wt) a 1.61E+00

Cadmium Surface Soil - Dist. 3 - 1,500 m Threshold Level - Plant Community 32 (mg/kg dry wt) a 6.69E+01

Cadmium Surface Soil - Dist. 3 - 1,500 m Threshold Level - Invertebrate Community 140 (mg/kg dry wt) a 2.93E+02

Cadmium Surface Soil - Dist. 4 - 3,500 m Threshold - Mammalian Insectivores (shrew) 0.36 (mg/kg dry wt) a 1.05E+00

Cadmium Surface Soil - Dist. 4 - 3,500 m Threshold - Avian Ground Insectivores (woodcock) 0.77 (mg/kg dry wt) a 2.24E+00

Cadmium Surface Soil - Dist. 4 - 3,500 m Threshold Level - Plant Community 32 (mg/kg dry wt) a 9.32E+01

Cadmium Surface Soil - Dist. 4 - 3,500 m Threshold Level - Invertebrate Community 140 (mg/kg dry wt) a 4.08E+02

Cadmium Surface Soil - Dist. 5 - 7,500 m Threshold - Mammalian Insectivores (shrew) 0.36 (mg/kg dry wt) a 2.99E+00

Cadmium Surface Soil - Dist. 5 - 7,500 m Threshold - Avian Ground Insectivores (woodcock) 0.77 (mg/kg dry wt) a 6.40E+00

Cadmium Surface Soil - Dist. 5 - 7,500 m Threshold Level - Plant Community 32 (mg/kg dry wt) a 2.66E+02

Cadmium Surface Soil - Dist. 5 - 7,500 m Threshold Level - Invertebrate Community 140 (mg/kg dry wt) a 1.16E+03

Cadmium Water-column Community Threshold Level 0.25 (ug/L) c 7.66E-01

Cadmium Water-column Community Frank-effect Level 2 (ug/L) c 6.12E+00
Table 1 – PB-HAP Benchmarks Included in the Environmental Risk Screen 

Dioxin Fish - Avian Piscivores NOAEL (merganser) 0.0000014 (mg/kg BW/day) f 3.17E-05

Dioxin Fish - Avian Piscivores LOAEL (merganser) 0.000014 (mg/kg BW/day) f 3.17E-04

Dioxin Fish - Mammalian Piscivores NOAEL (mink) 0.000000771 (mg/kg BW/day) f 4.12E-05

Dioxin Fish - Mammalian Piscivores LOAEL (mink) 0.00000771 (mg/kg BW/day) f 4.12E-04

Dioxin Sediment Community Threshold Level 0.00000116 (mg/kg dry wt) g 3.10E-05

Dioxin Surface Soil - Dist. 1 - 312 m Threshold - Mammalian Insectivores (shrew) 0.0000002 (mg/kg dry wt) h 6.69E-07

Dioxin Surface Soil - Dist. 2 - 850 m Threshold - Mammalian Insectivores (shrew) 0.0000002 (mg/kg dry wt) h 9.48E-07

Dioxin Surface Soil - Dist. 3 - 1,500 m Threshold - Mammalian Insectivores (shrew) 0.0000002 (mg/kg dry wt) h 1.28E-06

Dioxin Surface Soil - Dist. 4 - 3,500 m Threshold - Mammalian Insectivores (shrew) 0.0000002 (mg/kg dry wt) h 2.08E-06

Dioxin Surface Soil - Dist. 5 - 7,500 m Threshold - Mammalian Insectivores (shrew) 0.0000002 (mg/kg dry wt) h 4.39E-06

Dioxin Water-column Community Threshold Level 0.000012 (ug/L) i 3.84E-03

Dioxin Water-column Community Frank-effect Level 0.1 (ug/L) i 3.20E+01

Mercuric Chloride Sediment Community Threshold Level 0.15 (mg/kg dry wt) a 9.11E-03

Mercuric Chloride Sediment Community Probable-effect Level 0.7 (mg/kg dry wt) j 4.25E-02

Mercuric Chloride Surface Soil - Dist. 1 - 312 m Threshold Level - Plant Community 0.3 (mg/kg dry wt) k 9.25E-03

Mercuric Chloride Surface Soil - Dist. 1 - 312 m Threshold Level - Invertebrate Community 0.1 (mg/kg dry wt) k 3.08E-03

Mercuric Chloride Surface Soil - Dist. 2 - 850 m Threshold Level - Plant Community 0.3 (mg/kg dry wt) k 1.35E-02

Mercuric Chloride Surface Soil - Dist. 2 - 850 m Threshold Level - Invertebrate Community 0.1 (mg/kg dry wt) k 4.50E-03

Mercuric Chloride Surface Soil - Dist. 3 - 1,500 m Threshold Level - Plant Community 0.3 (mg/kg dry wt) k 1.78E-02

Mercuric Chloride Surface Soil - Dist. 3 - 1,500 m Threshold Level - Invertebrate Community 0.1 (mg/kg dry wt) k 5.93E-03

Mercuric Chloride Surface Soil - Dist. 4 - 3,500 m Threshold Level - Plant Community 0.3 (mg/kg dry wt) k 2.70E-02

Mercuric Chloride Surface Soil - Dist. 4 - 3,500 m Threshold Level - Invertebrate Community 0.1 (mg/kg dry wt) k 8.99E-03

Mercuric Chloride Surface Soil - Dist. 5 - 7,500 m Threshold Level - Plant Community 0.3 (mg/kg dry wt) k 7.23E-02

Mercuric Chloride Surface Soil - Dist. 5 - 7,500 m Threshold Level - Invertebrate Community 0.1 (mg/kg dry wt) k 2.41E-02

Mercuric Chloride Water-column Community Threshold Level 0.77 (ug/L) c 7.78E-01

Mercuric Chloride Water-column Community Frank-effect Level 1.4 (ug/L) c 1.42E+00

Mercury (methyl) Fish - Avian Piscivores NOAEL (merganser) 0.013 (mg/kg BW/day) f 7.55E-03

Mercury (methyl) Fish - Avian Piscivores LOAEL (merganser) 0.078 (mg/kg BW/day) f 4.53E-02

Mercury (methyl) Fish - Mammalian Piscivores NOAEL (mink) 0.0247 (mg/kg BW/day) e 4.01E-02

Mercury (methyl) Fish - Mammalian Piscivores LOAEL (mink) 0.123 (mg/kg BW/day) e 2.00E-01

Mercury (methyl) Sediment Community Threshold Level 0.2 (mg/kg dry wt) l 5.43E+00

Mercury (methyl) Sediment Community Probable-effect Level 1 (mg/kg dry wt) l 2.72E+01

Mercury (methyl) Surface Soil - Dist. 1 - 312 m Threshold Level - Invertebrate Community 0.67 (mg/kg dry wt) I 1.25E+00
Table 1 – PB-HAP Benchmarks Included in the Environmental Risk Screen 

References: 

a. U.S. EPA OSWER

b. Environment Canada

c. U.S. EPA OW

d. CA DTSC HERD (2009)

e. Sample, et. al, 1996

f. U.S. EPA 1995

g. U.S. EPA Region 3, 4, and 5.

h. U.S. EPA Region

i. U.S. EPA Region 4

j. Florida DEP, NOAA

k. ORNL and EPA R4, R6

l. MacDonald, et. al. 2000

m. U.S. EPA Region 6

n. NAAQS for Lead, Secondary 

Standard

Mercury (methyl) Surface Soil - Dist. 2 - 850 m Threshold Level - Invertebrate Community 0.67 (mg/kg dry wt) i 1.82E+00

Mercury (methyl) Surface Soil - Dist. 3 - 1,500 m Threshold Level - Invertebrate Community 0.67 (mg/kg dry wt) i 2.40E+00

Mercury (methyl) Surface Soil - Dist. 4 - 3,500 m Threshold Level - Invertebrate Community 0.67 (mg/kg dry wt) i 3.62E+00

Mercury (methyl) Surface Soil - Dist. 5 - 7,500 m Threshold Level - Invertebrate Community 0.67 (mg/kg dry wt) i 9.71E+00

Mercury (methyl) Water-column Community Threshold Level 0.0028 (ug/L) c 3.30E-01

Mercury (methyl) Water-column Community Frank-effect Level 0.099 (ug/L) c 1.17E+01

PAH Fish - Mammalian Piscivores NOAEL (mink) 0.417 (mg/kg BW/day) e 4.72E+02

PAH Fish - Mammalian Piscivores LOAEL (mink) 4.17 (mg/kg BW/day) e 4.72E+03

PAH Sediment Community No-effect Level 0.032 (mg/kg dry wt) b 4.73E+00

PAH Sediment Community Threshold Level 0.15 (mg/kg dry wt) l, h 2.22E+01

PAH Sediment Community Probable-effect Level 1.45 (mg/kg dry wt) l 2.14E+02

PAH Surface Soil - Dist. 1 - 312 m Threshold - Mammalian Insectivores (shrew) 1.52 (mg/kg dry wt) h 3.45E+00

PAH Surface Soil - Dist. 2 - 850 m Threshold - Mammalian Insectivores (shrew) 1.52 (mg/kg dry wt) h 5.09E+00

PAH Surface Soil - Dist. 3 - 1,500 m Threshold - Mammalian Insectivores (shrew) 1.52 (mg/kg dry wt) h 8.22E+00

PAH Surface Soil - Dist. 4 - 3,500 m Threshold - Mammalian Insectivores (shrew) 1.52 (mg/kg dry wt) h 2.02E+01

PAH Surface Soil - Dist. 5 - 7,500 m Threshold - Mammalian Insectivores (shrew) 1.52 (mg/kg dry wt) h 5.06E+01

PAH Water-column Community Threshold Level 0.014 (ug/L) a, h, m 1.84E+01

PAH Water-column Community Frank-effect Level 0.24 (ug/L) a 3.16E+02

Lead Ambient Air NAAQS Secondary Standard 0.15 ug/m3 n NA
 

Table 2 – Acid Gas Benchmarks Included in the Environmental Risk Screen 

a- Note that the human health RfC is 20 μg/m3, which is lower than the ecological benchmark.

Acid Gas Chronic 90-day Benchmark in μg/m3

Hydrochloric acid - LOEL 50a

Hydrofluoric acid – Plant Community LOEL 0.5

Hydrofluoric acid – Plant Community LOEL 0.4