Ikelic - Alliance Digital Repository

COAL
SOURCE: IGT
CONTAMINATED
SOIL
TREATED
SOIL
In Situ Solidification
FIGURE 1
BIOSLURRY REMEDIATION PROCESS
2'
Water
Tank
m
SCREEN
THICKENER
At an MGP site in Columbus, Georgia, gas was
produced from 1854 to 1931. In 1992 this site
became the target of an environmental cleanup
effort.
The analysis of ground water flow across the site
indicated a southwesterly flow of water and MGP
coal tar.
Boring and sampling activity indicated that a
bedrock layer identified as "saprolite,"
a
weathered granite material, underlay the site in
an undulating manner at a depth of ap
proximately
45 feet below the ground surface.
Due to the coal tar having a specific gravity
CHEMICALS
AIR-I
01
do
PEED HOPPER
& CONVEYOR
INOCULUM.
NUTRIENTS
AIR-i
ia Aim
f"l ATTRITION
SHAKER r\^'
SCREEN
CO do
BIO-
CHEMICAL SLURRY
REACTOR REACTOR REACTOR
4-45
SCRUBBER
? 20 fresh
OVERSIZE
greater than water, bore samples identified quan
tities of coal tar pooled at the surface of the
saprolite.
A containment plume of MGP waste was iden
tified in the groundwater in a prevailing southwes
terly
point area.
direction and downstream of the source
The selected strategy involved in situ stabilization
using a large vertical auger to directly treat and
immobilize 15 to 20 feet of MGP-affected soil
both above and below the water table (Figure 2).
Existing
clean fill above the water table was ex
cavated and stockpiled for reuse; pockets of
MGP-affected materials within the fill were stabi
lized by mixing with 10 percent portland cement.
THE SYNTHETIC FUELS REPORT, JANUARY 1995