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Interim Measures
Interim Measures are being conducted to mitigate a current or potential threat to human health and/or the environment. The IMs are estimated to represent approximately 30 percent of the required actions at CSSA. The IMs include Interim/Stabilization Measures WP (7 percent of IM), Interim Measures Implementation (70 percent of IM), and Reports (23 percent of IM). Based on information currently available at the end of Quarter 12, the IMs are approximately 46 percent complete.
Task I - Interim/Stabilization Measures Work Plan
Task Description
The Interim/Stabilization Measures WP includes:
A description of on-going and planned IMs;
A statement of the objectives of each interim/stabilization measure, including how the measure mitigates a potential threat to human health and the environment and is consistent with and integrated into any long-term remedy for CSSA; and
Proposed locations, design plans and specifications, construction, and operation and maintenance requirements of the IMs, including a sampling and analysis plan.
Existing plans, which are included in CSSA’s Environmental Encyclopedia, are referenced to the extent possible.
Interim/Stabilization Measures include initial sampling and analysis of groundwater from off-post wells; sampling and analysis of groundwater in CSSA wells; identification of all off-post water wells located within ¼-mile of the facility boundary; evaluation of alternative measures and implementation of selected interim measures at SWMU O-1; closure of SWMU O-1; characterization and determination of proper disposition of SWMUs B-8, B-20, B-24, B-28, and the Demolition Dud Area soil piles; and implementation of the identified disposition method. Continuation of on-post and off-post groundwater sampling and analysis is being performed under the RFI phase of this project. The status of each interim measure is described below.
An appropriate disposition method will be identified for the soil piles (under RL83). However, final implementation of the yet to be selected disposition method is not funded. Due to the amount of soil in these piles, it is anticipated that funding may be spread over several years.
A water well survey was conducted under RL83 to identify all wells within ¼-mile of the CSSA facility boundary. The final version of the Water Well Survey Report was submitted during Quarter 10 and is located in the Environmental Encyclopedia in Volume 5, Groundwater, Offsite Well Survey Report (August 2001).
Activities this Quarter
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Efforts relating to the determination of proper disposition of previously sifted soil piles at SWMUs B-8, B-20, B-24, B-28, and DD were continued in Quarter 12. The Draft Soil Pile Disposition Assessment Report will be continued, along with the initiation of bench-scale studies of other treatment technologies (e.g., density treatment, phytoextraction, etc.) during Quarter 12. |
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Operations and Maintenance O&M for the Phosphate-Induced Metals Stabilization (PIMS) treatability study on excavated lead-contaminated soils at SWMU B-20 was continued during Quarter 12. Initial results of the treatability study, which is being conducted by UFA Ventures and ESTCP with support from Parsons, are further discussed under Task VI (Treatability Studies). The UFA Ventures treatability study will be incorporated into Volume 4 of the CSSA Environmental Encyclopedia. The PIMS field scale treatability study monitoring efforts are expected to continue through August 2002. A final report of the PIMS treatability study is expected in September 2002. Sampling and monitoring of the treated soils at SWMU B-20 were continued with the monitoring of lysimeters that allow collection of rainwater from the site. Additionally, bioavailability testing of the site soils was conducted during quarter 12. |
Percent Complete
This task makes up approximately 7 percent of the IM phase and is 100 percent complete, based on the interim measures defined in the 3008(H) Administrative Order on Consent, located in Volume 1, Scoping Documents. If future modifications to the scope for Interim Measures Work Plans are made, the percent complete will be adjusted.
Task II - Interim/Stabilization Measures Implementation
Task Description
O-1 (closed) – This task included excavation and removal of contaminated soil related to SWMU O-1, collection and analyses of confirmation samples, backfilling with clean fill material, installation of clay cap, and completion of the closure report. The fieldwork for this task was completed in August 2000. The closure report was completed in October 2000. The TNRCC approved the SWMU O-1 closure on December 3, 2001.
Groundwater Sampling (complete) – This task included one round of groundwater sampling for all on-post monitoring wells and selected off-post water wells sampled in 1995. This sampling and analysis was complete in December 1999.
Off-post Well Survey (complete) – This task included identifying and locating all water wells within ¼-mile of the CSSA boundaries. The final report was issued in August 2001. Since this report was completed, two new private wells were identified at a distance greater than ¼-mile from the post boundary. These wells include OFR-3 and I10-7. OFR-3 was initially sampled in October 2001 and is included on a monthly sampling schedule due to elevated levels of volatile organic compounds (VOCs). I10-7 was sampled for the first time in March 2002. Additional wells and associated data are being tracked by both CSSA and Parsons. An amended well survey table will be issued with the next quarterly update to the CSSA Environmental Encyclopedia.
The Draft Soil Pile Disposition Assessment Report was completed, along with the initiation of bench-scale studies of other treatment technologies (e.g., density treatment, phytoextraction, etc.) during Quarter 12. Upon completion of the treatability studies on the subject soils, a final recommended disposition will be made. Planning and implementation of the final remedy will proceed once the final remedy has been selected for the excavated soils at SWMUs B-8, B-24, B-28, & DD. Soils from SWMU B-20 are being addressed under the PIMS Stabilization Treatability Study.
Percent Complete
This task makes up approximately 70 percent of the IM phase. This task is considered 37 percent complete, based on the current projected activities listed in Task II, Task Description. If investigation results at other sites indicate an immediate threat to human health or the environment so that IM activities are warranted at additional sites, the percent complete will be adjusted accordingly.
Summary of Findings
A total of approximately 1,515 cubic yards of contaminated soil were excavated and removed from SWMU O-1. Results from confirmation samples taken confirmed cleanup was complete. Closure of the soil unit portion of site was approved by TNRCC on December 3, 2001. Investigation and possible cleanup of the vadose zone and groundwater portions of the site are incomplete.
The Off-post Well Survey Report identified 162 potential water wells within ¼-mile of CSSA. Of these, 55 wells were somewhat outside the original ¼-mile radius searched and locations of 122 wells were field verified.
The initial round of groundwater monitoring conducted in 1995 was reported in the Groundwater Investigation and Associated Source Characterization Report, (June 1996) Volume 5, Groundwater. The findings from the initial round of groundwater monitoring indicated VOCs were present in on-post wells, but the four off-post wells sampled did not contain VOCs.
Leachate monitoring samples were taken from the SWMU B-20 soils that were treated with the PIMS Apatite II mineral. Samples were analyzed by APPL. Bioassessment of soils were conducted on PIMS treated and untreated soils from SWMU B-20 site. Results of monitoring and bioassessment analyses will be received in the next quarter.
Continued monitoring results from the PIMS treated B-20 soils test site located at SWMU B-10 indicate that there is no soluble lead available in the leachate. Analytical results for total lead after filtration were non-detect.
Summary of Changes
TNRCC approval of the SWMU O-1 closure report was received on December 3, 2001.
Summary of Contacts
No contacts were made regarding the IM activities during this Quarter.
Summary of Problems
No problems associated with IM activities occurred during this reporting period.
Actions Taken to Correct Problems
No actions to correct problems associated with IM activities were necessary this reporting period.
Projected Work for the Next Quarter
Contractor procurement activities associated with treatability studies for the soil piles continued in Quarter 12. These duties include generation of detailed statements of work for soliciting proposals for the planned treatability studies. Procurement of subcontractor services for the planned treatability studies at SWMUs B-8, B-24, B-28 and DD are expected to be complete during the next reporting period.
CSSA will continue with O&M activities for SWMU O-1 until a final remedy for the associated vadose and groundwater zone is complete. These continued O&M activities include watering the cap to maintain vegetative cover.
O&M activities associated with the PIMS treatability study are expected to continue through the next quarter. Activities include monitoring of leachate generated at the test sites and maintenance of vegetative cover at the SWMU B-20 test site.
Copies of Daily Reports, Inspection Reports, Data, etc.
There were no reports provided during this quarter.
Task Description
Reports associated with the IM include quarterly progress reports, environmental cleanup reports, groundwater monitoring reports, and an interim/stabilization measure report. This quarterly progress report is submitted as part of this task.
The O-1 IM/Closure Report documenting IM and RFI activities conducted at SWMU O-1 was completed in October 2000. The IM Report associated with SWMU O-1 was completely funded under RL74. IM reports for each of the soil pile sites have not been funded. The groundwater sampling task was funded under DO23 and RL74 and was completed in May 2000. The off-post well research project was funded under RL83 and completed in August 2001.
While determination of an appropriate disposition method for the soil piles is funded, actual completion of the soil pile IM will likely be spread over several years due to funding constraints. The IM Report will be in three phases. The first phase will be a baseline report, the second phase will be a progress report, and the third phase will be a final report upon completion of the project. Funding for the first two phases will be completed in the next fiscal year. Currently it is uncertain if the budget for the next fiscal year will fully fund the third phase, and may carry over to the following fiscal years.
Activities this Quarter
There were no reports provided during this quarter.
Percent Complete
This task makes up approximately 23 percent of the IM phase. This task is approximately 61 percent complete based on the current projected activities listed in Task III, Reports, Task Description. If investigation results at other sites indicate an immediate threat to human health or the environment so that IM activities are required at additional sites, the percent complete will be adjusted accordingly.
Summary of Findings
No findings associated with progress reports or IM reports are submitted this reporting period.
Summary of Changes
No changes associated with progress reports or IM reports occurred this reporting period.
Summary of Contacts
No contacts related to quarterly progress reports or IM Reports were made during this reporting period.
Summary of Problems
No problems were associated with Interim Measures reporting this quarter.
Actions Taken to Correct Problems