Soil/Sediment Inhalation

Equation 3 (non-radionuclides), equation 4 (radionuclides), and Table 3 present the exposure variables for the soil/sediment inhalation pathway for the residential, industrial, recreational, and agricultural scenarios. The particulate emission factor (PEF) is represented by the term that includes V, Um/Ut, F(x), Q/C, and CF3. The default PEF in SADA is 1.32E+9 (EPA 1996). The 1/VF term is only present if the contaminant is a volatile.

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Table 3. Soil/Sediment Inhalation Parameters

 

Parameter

 

Units

 

Residential

 

Industrial

 

Recreational

 

Excavation

 

Agricultural

 

Non-radionuclide chemical concentration in soil = Csn

 

mg/kg

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Radionuclide chemical concentration in soil = Csr

 

pCi/g

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Exposure frequency = EF

 

day/year

 

350

(EPA 1989a)

 

250

(EPA 1991a)

 

40

(EPA 1992)

 

20

 

350

(EPA 1989a)

 

Exposure duration = ED

 

years

 

30

(EPA 1989a)

 

25

(EPA 1991a)

 

30

(EPA 1989a)

 

1

 

30

(EPA 1989a)

 

Conversion factor = CF5

 

g/kg

 

1000

 

1000

 

1000

 

1000

 

1000

 

Volatilization factor = VF

 

m3/kg

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Chemical-specific

 

Fraction of vegetative cover = V

 

unitless

 

0.5

(EPA 1996)

 

0.5

(EPA 1996)

 

0.5

(EPA 1996)

 

0.5

(EPA 1996)

 

0.5

(EPA 1996)

 

Mean annual windspeed = Um

 

m/s

 

4.69

(EPA 1996)

 

4.69

(EPA 1996)

 

4.69

(EPA 1996)

 

4.69

(EPA 1996)

 

4.69

(EPA 1996)

 

Equivalent threshold value of windspeed at 7 m = Ut

 

m/s

 

11.32

(EPA 1996)

 

11.32

(EPA 1996)

 

11.32

(EPA 1996)

 

11.32

(EPA 1996)

 

11.32

(EPA 1996)

 

Function dependent on Um/Ut= F(x)

 

unitless

 

0.194

(Cowherd 1985)

 

0.194

(Cowherd 1985)

 

0.194

(Cowherd 1985)

 

0.194

(Cowherd 1985)

 

0.194

(Cowherd 1985)

 

Inverse of the mean concentration at the center of a 0.5 acre-square source = Q/C

 

(g m3)/

(m2 s kg)

 

90.8

(EPA 1996)

 

90.8

(EPA 1996)

 

90.8

(EPA 1996)

 

90.8

(EPA 1996)

 

90.8

(EPA 1996)

 

Seconds in an hour = CF3

 

s/h

 

3600

 

3600

 

3600

 

3600

 

3600

 

Total inhalation rate = IRair

 

m3/day

 

20

(EPA 1989a)

 

20

(EPA 1989a)

 

6.7

(8 hours)

(EPA 1992)

 

20

(EPA 1989a)

 

20

(EPA 1989a)

 

Conversion Factor = CF2

 

days/yr

 

365

 

365

 

365

 

365

 

365

 

Body weight = BW

 

kg

 

70 (adult)

(EPA 1991a)

 

70 (adult)

(EPA 1991a)

 

70 (adult)

(EPA 1991a)

 

70 (adult)

(EPA 1991a)

 

70 (adult)

(EPA 1991a)

 

Lifetime = LT

 

years

 

70

(EPA 1989a)

 

70

(EPA 1989a)

 

70

(EPA 1989a)

 

70

(EPA 1989a)

 

70

(EPA 1989a)

 

Averaging time = AT

 

years

 

LT (carcinogen)

ED (noncarcinogen)

 

LT (carcinogen)

ED (noncarcinogen)

 

LT (carcinogen)

ED (noncarcinogen)

 

LT (carcinogen)

ED (noncarcinogen)

 

LT (carcinogen)

ED (noncarcinogen)