Contaminant Risk Factors - Urban Watersheds: Geology, Contamination, and Sustainable Development - page 372

CRF (GW)

CRF (SOIL)

Arsenic

Chromium VI
DNAPL
Arsenic
Mercury
Lead
LNAPL
PAHs
PCBs

DNAPL

Chlordane

DNAPL

Mercury

PCBs

Chromium VI

Others

Others

CRF (AIR)

Chlordane

Chromium VI

PCBs

DNAPL

PAHs

Arsenic

Mercury

LNAPL
Lead

FIGURE 10.8
Pie charts of groundwater, soil, and air CRFs.

TABLE 10.15
Relative CRF Risk Rankings of Contaminants by Media

Compound CRF GW CRF SOIL CRF AIR

Chromium VI Extremely high Very low Very high

DNAPL High High Moderate

Arsenic Low Very low Moderate

LNAPL Very low Very low Moderate

Mercury Very low Extremely high Very high

Lead Very low Very low Low

PAHs Extremely low Very low Very high

Chlordane Extremely low Very high Very high

PCBs Extremely low Very high Moderate

watershed within a variety of geological environments. Using as input the variables listed
in Table 10.6, early iterations of the stepwise procedure on the Rouge River watershed data
set retained extent of contamination and the total risk scores to explain remediation cost.
Examination of the distribution of the dependent and independent variables indicated
the data were positively skewed. After a logarithmic transformation, and the multiplica-
tion of the total risk scores by plume length, the River Rouge data set indicates a strong