Remediation Status: In groundwater monitoring

Why the technology was selected:
A SVE/AS remedial system was installed at the site, primarily to address the impacts to groundwater in the source area, because of the favorable geology, relatively inexpensive costs, and ease of site access.

Date implemented:
The SVE/AS system was installed in October 2000.

Final remediation design:
The SVE/AS system consists of three SVE wells to 17 ft, six AS wells to 40 ft and 4 sets of nested wells for monitoring groundwater. Approximately 200 ft of trenching was needed for wellhead connections and piping. The remedial trailer houses the SVE/AS manifold, an SVE 10-hp PD blower, differential flow sensors, sampling ports, vacuum gages, see-through flow meters for each line, an AS 10-hp oil-less compressor, ball values, pressure gages, and flow meters on each line and aftercooler. The SVE system produced a vacuum of 20-inches of water at 140 cfm with an effective radius-of-influence of approximately 150 ft.

Results to date:
The SVE/AS and KVA systems reduced the chlorinated solvents to below the Kansas risk-based standards or to non-detect for those constituents. The systems were shut down in June 2002. The groundwater was monitored for 2 years to evaluate contaminant rebound; none was detected. Soil in the source area was collected for analysis at the end of this 2-year period. The compounds of concern were not detected above the Kansas risk-based standards. System abandonment was conducted in March 2005 (SVE/AS, KVA C-Sparger, and select monitoring wells were removed and properly abandoned). Select wells remain for long-term groundwater monitoring.

Next Steps:
Long-term monitoring

Cost to Design and Implement:
System Installation - KVA C-Sparger - $59,629; SVE/AS - $129,900

Why the technology was selected:
KDHE is committed to the use of innovative technologies for the cleanup of impacted soil and groundwater. In addition, the hydrogeology of the area is amenable to a variety of remedial technologies. The KVA C-Sparger system was able to be designed in a barrier-fence configuration to impede the migration of chlorinated solvents near the downgradient extent of the plume.

Date implemented:
The KVA C-Sparger system was installed in August 1998. The SVE/AS system was installed in October 2000.

Final remediation design:
The KVA C-Sparger system uses ozone injection in conjunction with air sparge and recirculation technology. The system includes four dual sparge-points that were installed approximately 750 ft downgradient of the site. The sparge points were installed approximately 60 ft apart, to a depth of approximately 45 ft bgs. The dual sparge-point well construction consists of a 3/4-inch PVC below-well sparge-point and a 4-inch PVC dual-screened well in a common borehole. The interconnected tubing and wiring from the sparge-points were placed in PVC casing in a trench with the SVE piping. The casing is connected to the control panel. The subsurface piping connects the remediation wells to the risers. Flex tubing connects the risers to the header within the equipment enclosure. Equipment consists of a 3/4-hp air compressor, a VOX-2 ozone generator, a programmable timer, flow meter, pressure gauge, and ring compressor. The blower is powered by a 0.11-hp, 115-volt, single-phase motor. The control panel pumps the air/ozone mixture to the four dual sparge-point wells. A submersible pump draws groundwater from the upper screen and discharges through the lower screen. The SVE portion of the KVA system is connected to each dual sparge-point well for removal of vapors. Three wells were installed for monitoring the groundwater.

Results to date:
The SVE/AS and KVA systems reduced the chlorinated solvents to below the Kansas risk-based standards or to non-detect for those constituents. The systems were shut down in June 2002. The groundwater was monitored for 2 years to evaluate contaminant rebound; none was detected. Soil in the source area was collected for analysis at the end of this 2-year period. The compounds of concern were not detected above the Kansas risk-based standards. System abandonment was conducted in March 2005 (SVE/AS, KVA C-Sparger, and select monitoring wells were removed and properly abandoned). Select wells remain for long-term groundwater monitoring.

Next Steps:
Long-term monitoring

Cost to Design and Implement:
System Installation - KVA C-Sparger - $59,629; SVE/AS - $129,900

Why the technology was selected:
A SVE/AS remedial system was installed at the site, primarily to address the impacts to groundwater in the source area, because of the favorable geology, relatively inexpensive costs, and ease of site access.

Date implemented:
The SVE/AS system was installed in October 2000.

Final remediation design:
The SVE/AS system consists of three SVE wells to 17 ft, six AS wells to 40 ft and 4 sets of nested wells for monitoring groundwater. Approximately 200 ft of trenching was needed for wellhead connections and piping. The remedial trailer houses the SVE/AS manifold, an SVE 10-hp PD blower, differential flow sensors, sampling ports, vacuum gages, see-through flow meters for each line, an AS 10-hp oil-less compressor, ball values, pressure gages, and flow meters on each line and aftercooler. The SVE system produced a vacuum of 20-inches of water at 140 cfm with an effective radius-of-influence of approximately 150 ft.

Results to date:
The SVE/AS and KVA systems reduced the chlorinated solvents to below the Kansas risk-based standards or to non-detect for those constituents. The systems were shut down in June 2002. The groundwater was monitored for 2 years to evaluate contaminant rebound; none was detected. Soil in the source area was collected for analysis at the end of this 2-year period. The compounds of concern were not detected above the Kansas risk-based standards. System abandonment was conducted in March 2005 (SVE/AS, KVA C-Sparger, and select monitoring wells were removed and properly abandoned). Select wells remain for long-term groundwater monitoring.

Next Steps:
Long-term monitoring

Cost to Design and Implement:
System Installation - KVA C-Sparger - $59,629; SVE/AS - $129,900