Case Studies: Successful and Unsuccessful Redevelopment of Contaminated Sites - Urban Watersheds: Geology, Contamination, and Sustainable Development - page 478

selected compounds that included DNAPL and LNAPL VOCs, PAHs, SVOCs, PCBs, and
heavy metals (As, Ba, Cd, Cr, Cu, Pb, Hg, Se, Ag, and Zn).
Several contaminants were detected in soil, including LNAPL and DNAPL VOCs; PAHs;
SVOCs; PCBs; and the heavy metals arsenic, cadmium, lead, and copper. Contaminants
detected in groundwater included DNAPL VOCs and low levels of LNAPL VOCs.
Contaminants requiring remediation included LNAPL and DNAPL VOCs, PAHs, SVOCs,
PCBs, lead and cadmium in soil and DNAPL VOCs in groundwater. Figure 14.16 shows
the location of soil borings and monitoring wells and the extent of contaminant impacts
requiring remediation.
The geology of the site was dominated by a thin sand layer that became thinner toward
the southern portion of the site. The thickness of the sand was less than 3 m in the northern
portion and only 1 m thick in the southern portion. Beneath the sand was a thick sequence
of clay more than 18 m (60 ft) thick and believed to be a glacial lodgment till deposit. The

N

Sump
location
(source)

DNAPL

VOC
groundwater
plumes

Leakage
into storm
sewer

Site
boundary

Outdoor
storage
areas
(source)

Outdoor storage,
pits, trenches, floor
drains

Leakage
into storm
sewer

Legend

Soil boring or
monitoring well

DNAPL

VOC
groundwater
plume

0 400 m

FIGURE 14.16
(See color insert.) Extent of impacts at Case Study 4.