The Carver's Circle Community in Grenada, MS has been affected by the local wood treater since the 1950's. Over the next 55 years Koppers and Beazers East successfully defended the position that the waste in the Community as well as the dying residents were due to the residents own activities. MDEQ and EPA Region 4 continued to ignore the problem until a change in Administration. The Culture of Disinfranchisement is so pervasive at EPA Region 4 that good people are not really allowed to make protective decisions.
Of the 30 something sites tested in Carvers Circle not one was unaffected ( clean). While only a few required clean up according to EPA Region 4. The most positive result of the EPA Region 4 intervention was to remove the assertion that the waste did not belong to Koppers/Beazers East. To make this perfectly clear: The WASTE BELONGS TO KOPPERS/BEAZERS EAST. Now my concern is the persistent, cumulative exposure of the residents and the persistent culture at EPA Region 4 which pays lip service only to Community Engagement. I was horrified to learn that sites were being cleaned up with out discussion with the affected Community. Open, Transparent, Equal Treatment is just a figment of our imiginations. Please Sign our Petition at: http://petitionbureau.org/COCEJR4
Interim Measures to Contain Creosote DNAPL at a Wood-Treating Facility
in Grenada, Mississippi, USA
by Peter A. Rich1, Robert M. Cohen1, Jennifer Abrahams2, Michael W. Bollinger3, Robert S.
Markwell3, and Mitchell D. Brourman3
A creosote wood treatment facility in Grenada, Mississippi, has treated railroad ties, utility poles, and lumber in pressurized cylinders using creosote since 1904. Former waste management practices at the facility resulted in the presence of creosote DNAPL and associated groundwater contamination in alluvium and stream sediments at the site. Stream sediments along the Central Ditch, which received discharge from former lagoon areas, were found to be significantly impacted by DNAPL.
In 1999, Interim Measures (IM) were initiated to mitigate further discharge of DNAPL into the ditch.
These IM activities included controlling mobile DNAPL by installing a sheet-pile barrier along the
north bank of the ditch, an underdrain system to extract DNAPL beneath the relined ditch, and
DNAPL recovery wells behind (and upgradient of) the sheet-pile barrier. As of March 2001, nearly
1900 gallons of DNAPL had been extracted from the ditch underdrain system, but little DNAPL had been recovered from the wells. Ongoing monitoring shows that the rate of DNAPL recovery is slowing. Impacted stream sediments were excavated from the Central Ditch prior to construction of the NAPL recovery underdrain system. The excavation began on-site and continued nearly one mile downstream to the mouth of the Batupan Bogue. Central Ditch reconstruction in the on-site area involved installing a DNAPL recovery system and liner. Trenches were excavated in the on-site
Central Ditch to construct the DNAPL recovery system, which includes of eight underdrain sumps (Figure 1). Each underdrain sump consists of the following: nonwoven geotextile fabric covering the trench and bench; #57 stone; 4-inch diameter perforated pipe; clean backfill; geosynthetic clay liner (GCL Bentomat CL); a structural fill layer; woven geotextile; and, riprap covering the drains to complete the reconstruction. Underdrain #1 through 5 were constructed with a typical drain pipe length of 60 feet in length. Underdrain #6 is approximately 90 feet long. Each underdrain consists of a 4-inch diameter high-density polyethylene (HDPE) horizontal perforated filter pipe that empties into a 12-inch diameter vertical sump with an approximately 20 gallon reservoir at the downstream end. The sump extends above the final riprap grade of the Ditch as does a 4-inch diameter cleanout at the upstream end of each drain.
GCL Bentomat® CL panels were placed over the clean fill covering the underdrains. The GCL
Bentomat® CL was sealed to the upstream weir and the sheet pile cutoff wall. The GCL Bentomat® L panels were covered with one foot of structural fill. Size R-90 riprap was placed on geotextile fabric over the structural fill layer to reinforce the ditch. DNAPL was pumped from the underdrain sumps after the completion of the Central Ditch reconstruction. A total of 1,885 gallons of DNAPL have been recovered as of March 2001. A summary of the DNAPL collection from the underdrain system is provided in Figure 2.
Recovered DNAPL was collected in 55-gallon drums staged upgradient of the cutoff wall on the
access road. All drums filled with DNAPL were labeled, capped and secured prior to transport offsite to a licensed facility. One upstream concrete weir was installed to maintain channelized flow in the reconstructed ditch to prevent erosion under the railroad bridge. Two grade control structures, located immediately downgradient of the property line, were constructed to maintain channelized flow in order to protect the reconstructed on-site ditch and limit scouring of the ditch. The grade control structures consist of the following: weirs (vertical barriers installed perpendicular to the water flow in the ditch); underdrain sumps; drain filter stone; a non-woven geotextile; backfill; and, GCL Bentomat® CL. The rade control structures, also referred to as low-drop structures, were constructed after impacted sediments from the ditch bottom, slopes and buried channel deposits were excavated. The grade control structure weir sheet pile panels were installed with a vibrating hammer suspended from a crane. Once the panels were placed, the upper panel edges were cut with an acetylene torch so the top of the panels matched the final ditch grade profile.
A sheet pile cutoff wall was designed to inhibit DNAPL migration to the Central Ditch. The cutoff
wall is located in the north bank of the on-site Central Ditch (see Figure 1). Construction details of
the cutoff wall are presented on Figure 3. The interlocking edges of the sheet pile panels were
aligned and the panels were vibrated into the ground with a vibrating hammer. The sheet pile panel interlocks were flushed and cleaned after the entire cutoff wall was installed. The panel interlocks were sealed with CETCO’s “PureGold Grout.” Interlocks noted to contain DNAPL during flushing activities were cleaned with a detergent designed to remove DNAPL.
Nine pilot test borings (RW1 to RW9) were installed to 20 feet below ground surface to characterize subsurface conditions and the presence of NAPL immediately adjacent to and north (upgradient) of the cutoff wall. Five of the pilot borehole locations were selected for DNAPL recovery well construction based on observation of DNAPL in the pilot boreholes. The boreholes for the DNAPL recovery wells were drilled with a mud rotary rig, and a 7 5/16 -inch inner-diameter well was constructed. The DNAPL recovery wells are constructed of HDPE pipe. Each well has a 10-foot HDPE screen with a 3-foot sump. As of March 2001, less than 50 gallons of NAPL had been collected from the five recovery wells.
DNAPL will be pumped from the underdrain recovery sumps and recovery wells to deplete mobile DNAPL and further reduce the potential for DNAPL to migrate to the surface water environment. The quantities removed will be evaluated periodically to optimize the recovery pumping schedule and protocol.