19^th Quarterly Progress Report

RCRA Facility Investigation

The RFI is being conducted to characterize the environmental setting of CSSA, define the sources of contamination, define the degree and extent of contamination, identify actual or potential receptors, and to assess whether any additional I/SM may be warranted. The RFI is estimated to represent approximately 30 percent of the required actions at CSSA. The RFI includes a Preliminary Report (5 percent of RFI), RFI WP (10 percent), Facility Investigation (45 percent), Human Health and Ecological Risk Assessment (15 percent), Investigation Analysis (10 percent), Treatability Studies (10 percent), and Progress Reports (5 percent). As of the end of Quarter 19, the RFI is approximately 41 percent complete.

Task I - Preliminary Report: Description of Current Conditions

Task Description

This task included preparation of the DCC Report. The DCC Report included information from previous investigations and other relevant data. Information related to the facility background, nature and extent of contamination and pre-investigation evaluation of corrective measure technologies was included in the DCC Report. CSSA’s Environmental Encyclopedia was used to meet the DCC Report submittal requirements. The final DCC Report was submitted to the EPA and TCEQ on August 1, 1999. No regulatory comments have been received on the report. This task makes up approximately 5 percent of the RFI phase, and is 100 percent complete.

Activities this Quarter

No activities associated with the DCC were conducted this period.

Task II - RFI Work Plan

Task Description

The Order requires that the RFI WP task include a Project Management Plan, Data Collection Quality Assurance Plan, Health and Safety Plan (HSP), and a Community Relations Plan (CRP). As previously agreed by EPA, CSSA’s Environmental Encyclopedia has been used to fulfill this requirement. The Environmental Encyclopedia includes all the information required by the Order. Completion of this task is funded for the planned RFI tasks.

Activities this Quarter

Closure activities were conducted at eleven SWMUs and AOCs during this quarter. The Task Order (TO) 0019 Environmental Cleanup Plan (ECP) was made Final and placed in the CSSA Environmental Encyclopedia in December 2003. The TO 0058 O&M WP for the two soil vapor extraction (SVE) systems (subslab and treatability study) installed at AOC-65 was finalized in November 2003. Final TO 0008 WPs (WP, HSP and SAP) for continued quarterly groundwater monitoring were added to the CSSA Environmental Encyclopedia in December 2003.

1. Percent Complete

The RFI WP task makes up approximately 10 percent of the RFI phase. Estimation of percent complete is difficult due to the continuing need for plan addenda as new TOs are added. As of the end of Quarter 19, WPs currently under scope are approximately 90 percent complete. The CSSA Environmental Encyclopedia will continue to be updated as WPs are completed and made Final.

2. Summary of Findings

No new findings are associated with RFI WP preparation during this reporting period.

3. Summary of Changes

No changes other than those described above in Activities this Quarter to existing RFI WP were made during this reporting period.

4. Summary of Contacts

No contacts occurred during this reporting period.

5. Summary of Problems

No significant problems occurred during this reporting period.

6. Actions Taken to Correct Problems

No actions were taken for any problems during this reporting period.

7. Projected Work for the Next Quarter

WPs for continued CSSA contracts will be prepared as needed.

8. Copies of Daily Reports, Inspection Reports, Data, etc.

No daily reports, inspection reports, or data related to the RFI WP task were generated during this reporting period.

Task III - Facility Investigation

Task Description

An investigation of the facility is being conducted to:

1. Characterize the environmental setting of the facility;

2. Define the source(s) of contamination;

3. Define the nature and extent of contamination; and

4. Identify actual or potential receptors.

In some cases, multiple investigational phases may be necessary. The investigation results will be used to develop and evaluate alternatives during the CSM. All investigation activities are being conducted in accordance with the RFI WP.

Completion of this task is partially funded for the planned RFI tasks. Attachment 2 indicates the sites for which investigations have been initiated and subsequently conducted as well as sites that have been identified, but not yet investigated.

Activities this Quarter

The majority of current ongoing environmental activities at CSSA are part of the RFI task. Work on each of these tasks is described in the following paragraphs. The main areas of work this quarter include groundwater monitoring, maintenance of the off-post granular activated carbon (GAC) wellhead treatment systems, analytical data verification and validation, RFIs and closures of several SWMUs and AOCs, well installations, Building 90/AOC-65 investigations, SWMU B-3 SVE system, AOC-55 remediation activities, and various miscellaneous tasks.

Groundwater Monitoring

Sampling of all on-post and selected off-post wells is conducted quarterly. Off-post wells were sampled from December 1 - 4, 2003. Twenty-nine private and public off-post drinking water wells were sampled, including FO-J1, FO-22, HS-2, I10-2, I10-5, JW-7, JW-8, JW-9, JW-14, JW-26, JW‑28, JW-29, JW-30, LS-1, LS-2, LS-3, LS-4, LS-5, LS-6, LS-7, OFR-1, OFR-2, OFR-3, RFR‑3, RFR-6, RFR-7, RFR-10, RFR-11, and RFR-12. All samples were collected from ports located near the wellhead. The locations of these wells are shown on Attachment 1. Samples were analyzed by Agriculture & Priority Pollutants Laboratories, Inc. (APPL) for the EPA-approved short list of volatile organic compounds (VOCs). The VOC short list includes 1,1-dichloroethene, bromodichloromethane, bromoform, chloroform, cis-1,2-dichloroethene (DCE), dibromochloromethane, dichlorodifluoromethane, methylene chloride, naphthalene, tetrachloroethene (PCE), trichloroethene (TCE), toluene, trans-1,2-dichloroethene, and vinyl chloride. Preliminary data on these samples were received on December 29, 2003 by Parsons. Data validation and verification for these samples were initiated this quarter.

Quarterly groundwater monitoring of 38 on-post monitoring and/or drinking water wells was performed from December 8 - 16, 2003. CSSA wells CS-1, CS-2, CS-4, CS-9, CS-10, CS-11, CS-D, CS-I, CS-MWG-LGR, CS-MWH-LGR, CS-MW1-BS, CS-MW1-CC, CS-MW1-LGR, CS-MW2-LGR, CS-MW2-CC, CS-MW3-LGR, CS-MW4-LGR, CS-MW5-LGR, CS-MW6-BS, CS-MW6-CC, CS-MW6-LGR, CS-MW7-CC, CS-MW7-LGR, CS-MW8-CC, CS-MW8-LGR, CS-MW9-BS, CS-MW9-CC, CS-MW9-LGR, CS-MW10-CC, CS-MW10-LGR, CS‑MW11A‑LGR, CS-MW12-BS, CS-MW12-CC, CS-MW12-LGR, CS-MW16-LGR, CS‑MW17-LGR, CS‑MW18-LGR, and CS-MW19-LGR were sampled. Locations of the on-post wells sampled are shown on Attachment 1. Samples were analyzed by Severn Trent Laboratories (STL) for the EPA-approved short list of VOCs. The preliminary data were received by Parsons on January 14, 2004. Data validation for VOCs, metals, and cations and anions was initiated this quarter.

The Final On- and Off-post Quarterly Groundwater Monitoring Reports for September 2003 were added to Volume 5 of the Environmental Encyclopedia this quarter. Preparation of the Draft December Quarterly Groundwater Monitoring Reports was initiated this quarter.

The Final Data Quality Objectives (DQOs) for the Groundwater Investigation were added to the CSSA Encyclopedia in December 2003.

Off-Post GAC Systems

Based on previous sampling results indicating VOC levels above or approaching the maximum contaminant level (MCL), GAC filtration systems were installed at seven off-post wells. In accordance with the CSSA Off-post Monitoring Program Response Plan dated June 2002 (the Plan), the off-post GAC wellhead treatment systems are maintained by CSSA. Monthly O&M activities for the off-post residential GAC treatment systems were performed this quarter. Work included inspection and replacement, as needed, of the pre- and post-GAC micron filters at wells LS-6, LS-7, RFR-10, RFR‑11, and OFR‑3. Confirmation post-GAC samples were collected from these wells and LS-2/LS-3 during September 2003. No post-GAC samples had concentrations above the method detection limit (MDL) for PCE, TCE, or cis-1,2-DCE during the September event. The next post-GAC sampling event will be conducted in March 2004.

Data Validation and Verification

Laboratory results from sampling efforts and investigations are validated and verified by Parsons’ chemists to ensure results are in compliance with CSSA Quality Assurance Program Plan (QAPP) requirements. Data validation and verification continued during Quarter 19 under CSSA projects TO 0019, TO 0008, TO 0042, TO 0058, RL83, and TO 0009.

Data packages related to quarterly groundwater monitoring activities consist of groundwater monitoring conducted on- and off-post during Quarter 19 (the December 2003 quarterly sampling event). Data packages related to Westbay^® multi-port well groundwater sampling, investigation derived waste (IDW), soil gas vapor sampling, air emissions, waste characterization, and soil sampling for investigations at various SWMUs and AOCs were also validated and verified. Verification of these data packages continued during Quarter 19. AFCEE chemists approved data package groups TO 0009 Group D and TO 0008 Groups A, B & C, this quarter.

RCRA Facility Investigations/Closures of SWMUs and AOCs

A total of 84 SWMUs, AOCs, and Rifle Management Units (RMUs) have been identified at CSSA and investigations have been conducted at 59 of those sites. A summary of the status of each site, including whether the site is recommended for closure or if closure is approved, is provided in Attachment 2. Closure Reports were approved by TCEQ for SWMU Building 40 on January 4, 2004, and for SWMU B-32 on November 25, 2003. To date, closure of 20 sites has been approved by TCEQ.

During Quarters 19 and 20, soil/waste investigations and/or excavations were conducted at SWMUs B-2, B-11, B-12, B-23, B-23A, B-25, B-26, B-29, B-30, AOC 50, and DD. Evidence of ordnance waste was observed at SWMU B‑29 and AOC-56; therefore, further work was suspended at these sites until ordnance specialists could be mobilized to the site. A brief summary of the investigation/excavation results follows:

Well Installations

There are currently 41 drinking water, livestock, and monitoring wells at CSSA that are monitored on a quarterly basis. In addition, there are four multi-port wells that are sampled on monthly basis. Finally, there are 10 shallow wells and piezometers around Building 90 that are used for the AOC-65 treatability investigation.. TO 0042 funded the installation of 17 new monitoring wells: 11 wells to be completed in the Upper and Lower Glen Rose Formation (including four Westbay^®-equipped wells), two in the Bexar Shale, and four in the Cow Creek Formation. In addition, five upgrades to existing wells were completed under TO 0042 (CS-16, CS-G, CS-I, CS‑MW1-LGR, and CS-MW2-LGR). At the end of Quarter 19, the well upgrades and the installation of the 17 new monitoring wells under TO 0042 were complete.

Formation pressures in each sample zone were profiled four times during Quarter 19 (November 17, November 20, December 16, 2003 and January 12, 2004. Three rounds of sampling from the Westbay^® multi-level wells were conducted during the weeks of November 17, 2003, December 15, 2003, and January 19, 2004. Each well was hydraulically profiled by zone and discrete samples were collected from groundwater-bearing intervals. The samples were submitted to DHL Analytical for VOC analysis.

Because testing indicated low levels of VOC contamination, groundwater and drilling fluids produced during drilling efforts at the Westbay^® locations were contained and treated at the CSSA GAC unit and discharged at Texas Pollutant Discharge Elimination System (TPDES)-permitted Outfall 002. Parsons operated and maintained the GAC unit, and prepared a Discharge Monitoring Report (DMR) each month to comply with TPDES requirements. Through January 2004, approximately 9,000 gallons of water containing VOCs was treated by GAC and discharged from Outfall 002 during Quarter 19. Parsons is currently coordinating for the testing, disposal, and replacement of the activated carbon canisters located at the GAC unit.

Building 90/AOC-65 Investigation

Also under TO 0058, groundwater sampling was performed from the six piezometers and four of five shallow monitoring wells located west of Building 90 during the week ending January 23, 2004. This sampling was triggered by the first period of significant rainfall (>1 inch over multiple days) in over six months. In addition to the sample collection from these wells, AOC65-VEW15 and -VEW16 were purged to determine if the high water levels present within these wells are related to trapped water or from some other source (such as a pipe leak). Samples were also collected from these VEWs to assess the contaminant levels present in this water. These samples collected as part of the recharge study were dropped off at the laboratory for testing.

AOC-55 Excavation

Removal actions at AOC-55 were continued during Quarter 19. Approximately 35,000 cubic yards of soil were sifted for removal of ordnance and explosive (OE) scrap material, which was demilled and sent as scrap metal for recycling. Class 2 non-hazardous soil was the bulk of the transported and disposed of soil at the Waste Management, Inc., Covel Gardens facility. The removal effort at AOC-55 was completed during Quarter 19.

Approximately 699 OE scrap items have been discovered at AOC-55, many found at depths greater than two feet. The OE items include 75mm projectiles, 155mm projectiles, rocket propelled grenades and Stokes mortars. Approximately 20 of the items of UXO may still contain high explosive filler; however, none were found to be fused. The OE scrap items were demilled and sent off-site for scrap metal recycling after inspection and certification by the UXO specialists to confirm that none of the items contain explosives. The 20 items potentially containing high explosive fillers were removed by Fort Sam Houston EOD personnel.

Confirmation sampling of AOC-55 perimeter soils and excavated bottom was conducted in order to gain RRS1 closure. This testing identified a small area where further excavation will be needed. This additional excavation and the closure report for AOC-55 is expected to be completed during Quarter 20.

Miscellaneous

Preparation of the hydrogeologic conceptual site model (CSM) funded under RL83 continued during Quarter 18. Work on the CSM focused on the AOC-65 area in preparation for the installation of multi-level monitoring points (Westbay^®-equipped wells) in the vicinity of Plume 2. Detailed cross-section stratigraphic analysis was conducted to best determine the locations and zones to monitor. The geologic model is being prepared using the Rockworks^® software package to visualize the subsurface conditions. Preparation and submittal of the Final Well Installation Report for cluster wells installed under RL83 was completed during Quarter 17.

Letters summarizing the results of the September 2003 off-post groundwater monitoring were mailed to the owners of the off-post wells on December 1, 2003. Preparation of Fact Sheet 17, summarizing the findings of the December 2003 quarterly groundwater monitoring event were initiated this Quarter. The draft Fact Sheet 17 and draft letters to the well owners will be submitted to CSSA for review during Quarter 19.

The CSSA website was updated with documents added to the Environmental Encyclopedia through the end of December 2003. This website includes CSSA’s Administrative Record as required under the Order.

Parsons personnel conducted various LAN support activities during Quarter 19. Parsons personnel provided basic computer desk side support for the CSSA Environmental Office, upgraded a server to Windows 2003, configured and installed Microsoft ISA Server, verified the Microsoft Exchange Mail server and Active Directory restoration process and researched and specified hardware and software needs for 2004.

1. Percent Complete

The Facility Investigation task makes up approximately 45 percent of the RFI phase. As of the end of Quarter 18, this task is approximately 25 percent complete.

2. Summary of Findings

Groundwater Monitoring

Quarterly groundwater monitoring for both on- and off-post wells was performed at CSSA from December 1 - 16, 2003. A map of the well locations sampled is provided on Attachment 1 of this report. This figure includes monitoring well installations completed through December 2003.

On-post Wells, December 2003: Thirty-eight on-post monitoring and/or drinking water wells were sampled, including CS-1, CS-2, CS-4, CS-9, CS-10, CS-11, CS-D, CS-I, CS‑MWG‑LGR, CS-MWH-LGR, CS-MW1-BS, CS-MW1-CC, CS-MW1-LGR, CS‑MW2‑LGR, CS-MW2-CC, CS-MW3-LGR, CS-MW4-LGR, CS-MW5-LGR, CS-MW6-BS, CS-MW6-CC, CS-MW6-LGR, CS-MW7-CC, CS-MW7-LGR, CS-MW8-CC, CS-MW8-LGR, CS-MW9-BS, CS-MW9-CC, CS-MW9-LGR, CS-MW10-CC, CS-MW10-LGR, CS‑MW11A‑LGR, CS-MW12-BS, CS-MW12-CC, CS-MW12-LGR, CS-MW16-LGR, CS‑MW17-LGR, CS‑MW18-LGR, and CS-MW19-LGR were sampled. Samples were analyzed by STL. Results of the December 2003 groundwater monitoring event will be formally reported in the draft December 2003 Quarterly Groundwater Monitoring Report to be submitted to CSSA and AFCEE for review and comments during Quarter 19.

Off-post Wells, September 2003: Twenty-nine private and public off-post drinking water wells were sampled, including FO-J1, FO-22, HS-2, I10-2, I10-5, JW-7, JW-8, JW-9, JW-14, JW-26, JW‑28, JW-29, JW-30, LS-1, LS-2, LS-3, LS-4, LS-5, LS-6, LS-7, OFR-1, OFR-2, OFR-3, RFR‑3, RFR-6, RFR-7, RFR-10, RFR-11, and RFR-12. All samples were analyzed by APPL. Results of the off-post groundwater monitoring will be formally reported in the draft December 2003 Quarterly Groundwater Monitoring Report to be submitted to CSSA and AFCEE during Quarter 20.

Building 90/AOC-65 Investigation

There is no new analytical data available for review for Quarter 19. Observations from the purging activities will be presented in the Treatability Evaluation Report prepared under TO 0058. AOC65-VEW15 and -VEW16 purge results will be presented next quarter.

3. Summary of Changes

No changes to the RFI were made during the reporting period.

4. Summary of Contacts

Results from the September 2003 quarterly groundwater monitoring event were mailed to each off-post well owner. In addition, CSSA received several letters from the TCEQ during Quarter 19. The following correspondence was submitted and/or received:

	September 22, 2003 - CSSA submitted drinking water information to TCEQ concerning lead, copper, and a residual chlorine compliance sampling conducted at CSSA.
	September 24, 2003 - CSSA submitted additional information to TCEQ concerning the off-post quarterly groundwater monitoring program and the off-post short list of VOCs.
	September 26, 2003 - CSSA submitted the Closure Report for SWMU Bldg 40.
	November 4, 2003 - TCEQ issued approval of March 2003 Off-post Quarterly Groundwater Monitoring Report.
	November 25, 2003 - CSSA submitted response to TCEQ letter dated September 5, 2003, concerning closure of SWMU B-32.
	November 25, 2003 - TCEQ issued approval of final closure for SWMU B-32
	December 23, 2003 - TCEQ issued approval of the RL83 Final Well Installation Report
	January 5, 2003 - TCEQ issued approval of final closure for SWMU Bldg 40.

Copies of all correspondence are included in Volume 1-1 of the Environmental Encyclopedia.

5. Summary of Problems

No significant problems were encountered during the reporting period.

6. Actions Taken to Correct Problems

No actions beyond those previously reported for the data package review and approval process have been taken to correct problems.

7. Projected Work for the Next Quarter

Fact Sheets

Fact Sheet 17, summarizing the findings of the December 2003 Quarterly Groundwater Monitoring will be prepared and submitted to CSSA and AFCEE. After approval, the fact sheet will be distributed to area residents. Draft letters to the well owners were prepared this Quarter and will be submitted to CSSA for review during Quarter 21.

Groundwater Monitoring

The next quarterly groundwater monitoring event will be conducted in March 2004. The upcoming event will include the existing CSSA drinking water and monitoring wells, approximately 25 off-post wells (VOCs only). On- and off-post quarterly sampling will be funded under TO 0008 in March 2004. O&M at the residential GAC filtration systems (LS-6, LS-7, OFR-3, RFR-10, and RFR-11) and public water supply systems (LS-2/LS-3) will be conducted monthly during Quarter 20.

The Westbay^® wells will be profiled twice a month and sampled once per month for the foreseeable future. Monitoring frequencies may be modified based on the occurrence of significant rainfall.

Building 90/AOC-65 Investigation

O&M of the SVE systems at AOC-65 will be continued during the next quarter. Additionally under TO 0058, groundwater sampling of the AOC 65 piezometers will be performed in accordance with the Standard Operating Procedures (SOPs) and DQOs prepared for the groundwater recharge study. Analytical data from groundwater sampling performed in January 2003 will be reviewed and compiled into tables for eventual use in the Groundwater Recharge Study Report. Additional workplans will be prepared as new contracts are funded.

AOC-55 Excavation

Closure reporting for AOC-55 is expected to be completed during Quarter 20.

SWMU and AOC RFI/Closure Reports and Planned Closure Projects

Closure work recommended in previous RFI Reports will be continued at several SWMUs and AOCs during Quarter 20.

8. Copies of Daily Reports, Inspection Reports, Data, etc.

Reports summarizing the most recent groundwater findings are submitted to present the results from quarterly groundwater sampling events (on- and off-post). The quarterly groundwater monitoring reports present the groundwater elevations recorded (on-post wells only) and the analytical results received for each well (on- and off-post). The groundwater elevations are presented in the On-post Quarterly Groundwater Monitoring Reports on a potentiometric surface map and in tabular format. Analytical results from the most recent sampling events are compared to levels from the previous quarters, while comprehensive historical analytical results can be found in tables which are revised quarterly and presented in the Introduction to the Quarterly Groundwater Monitoring Program, Volume 5, Groundwater. Reports for each previously conducted quarterly monitoring event are also located in Volume 5, Groundwater, behind the On-post Groundwater Monitoring and Off-post Groundwater Monitoring tabs. Copies of these reports and analytical data are presented separately to the EPA by electronic version on CD Rom, at the request of the EPA. The CD Rom was delivered to the EPA within three weeks following the submittal of each quarterly progress report.

Preliminary groundwater data for the December 2003 on- and off-post sampling event were received by Parsons during Quarter 19. Various screening data packages were received under TO 0042, TO 0058, and TO 0009 delivery orders (DOs). SWMU investigation data packages were received under RL83, TO 0009, and TO 0019. These data packages were verified by Parsons’ chemists during this quarter and will be submitted to AFCEE for approval during Quarter 20.

Laboratory audit findings were forwarded to APPL on July 17, 2003, and APPL’s responses were received on September 5, 2003. CSSA/AFCEE/Parsons comments were forwarded to APPL on September 26, 2003 with request for further information and/or documentation to be submitted by October 31, 2003. APPL provided responses to AFCEE/Parsons' second set of comments on October 5, 3003. Parsons chemist reviewed the responses and recommended to AFCEE for acceptance on November 5, 2003. Final approval letter from AFCEE/Parsons were issued on January 14, 2004.

Task IV - Human Health and Ecological Risk Assessment

Task Description

This task includes a screening risk assessment, or if necessary, a baseline risk assessment for the potential human health and environmental risks posed by the site in the absence of any remedial action. For human health risks, this effort will involve the following components:

1. Contaminant Identification;

2. Exposure Assessment;

3. Toxicity Assessment; and

4. Risk Characterization.

For ecological risks, the effort will include the following components:

1. Problem Formulation;

2. Exposure Assessment;

3. Ecological Effects Assessment; and

4. Risk characterization.

Completion of this task is partially funded. Currently planned and funded (under RL83) is preparation of a preliminary post-wide human health and ecological CSM for risk assessment. The CSM identifies potential human and ecological receptors and land use surrounding the facility. In addition, a Risk Assessment Technical Approach has been prepared.

This task makes up approximately 15 percent of the RFI phase. The amount of effort needed to accomplish this task is not yet known because analytical data have not yet been fully evaluated. The percent complete will depend on the number of sites requiring risk assessment and is currently estimated at 30 percent.

Task V - Investigation Analysis

Task Description

This task includes preparation of an Investigation Analysis to support the selection of protection standards for CSSA. For sites closing under the State of Texas RRSs, this analysis will be included as part of the RFI Report. For sites closing to a risk-based standard, the analysis will be submitted along with the Risk Assessment Report. Background levels will be used to determine the possibility of closure under RRS1. The Investigation Analysis will also include groundwater protection standards and other relevant protection standards. The relevant protection standards will be used at sites where an RRS1 closure is not applicable. Due to the promulgation (September 23, 1999) of the Texas Risk Reduction Program (TRRP) (30 Texas Administrative Code [TAC] §350) by the TCEQ, two options are being considered for the protection standards. One option is to base the protection standards on the RRS2 Media-Specific Concentrations. The other option is to use the Protective Concentration Limits developed under TRRP. Site-by-site decisions will be made as additional information becomes available. New TO 0019 seeks closure of SWMUs and AOCs under the RRS.

Activities this Quarter

No activities related to Investigation Analysis this quarter.

1. Percent Complete

The Investigation Analysis task makes up approximately 10 percent of the RFI phase, and is approximately 69 percent complete.

2. Summary of Findings

As described in Task III, 49 final RFI reports have been completed and submitted to CSSA and TCEQ. As part of the preparation of these reports, investigation results were compared to closure criteria. A summary of recommendations for each site is provided in Attachment 2. Based on the final reports submitted through Quarter 19, 20 sites were recommended for closure while the remaining sites may require future investigation and/or cleanup. Through January 2004, a total of 20 SWMUs or AOCs have been approved by TCEQ for closure.

3. Summary of Changes

No changes associated with the Investigative Analysis were made during this reporting period.

4. Summary of Contacts

No contacts related to the Investigative Analysis were made during this reporting period.

5. Summary of Problems

No problems related to the Investigative Analysis occurred during this reporting period.

6. Actions Taken to Correct Problems

No actions to correct problems were necessary during this reporting period.

7. Projected Work for the Next Quarter

Continued work on comparison of investigation results to closure criteria will be performed.

8. Copies of Daily Reports, Inspection Reports, Data, etc.

No daily reports, inspection reports, or data related to investigation analysis/risk assessment were generated during this reporting period.

Task VI - Treatability Studies

Task Description

Funded activities include bench-scale treatability studies for SWMU B-20, SVE, and other treatability studies for treatment of the subsurface soils and bedrock at AOC-65 and SWMU B-3 if further contamination exists.

Activities this Quarter

As part of the Task II I/SM, a treatability study for stabilization of the excavated soils was continued during Quarter 19. Additional soil characterization data was generated during quarter 19 for the <2mm soil fraction at SWMU B-20. Monitoring of the field treatment efforts is expected to continue. Monitoring data are anticipated to support similar closure/remediation efforts at sites with similar contaminants of concern.

AOC-65 SVE System

O&M activities of the SVE system under TO 0058 were initiated during the first week in December 2003 and continued through the remainder of Period 19 in accordance with the O&M plan. Some preliminary testing of the plumbing network and manifold were performed in November 2003. It was discovered that there were some aberrations with air flow and pressure responses measured at the well-heads. Several hypotheses were evaluated to try and solve these aberrations before beginning the six-month O&M period (per TO 0058). It was determined that the likely cause of flow disruption in the vapor extraction wells (VEWs) closer to the Building 90 dock is related to high water levels in the extraction well blocking the screened interval. The cause of the high water is unknown since it has not rained appreciably in the past six months. Evaluation of the high water will be the subject of continued evaluation at the site.

SWMU B-3 SVE System

The installation of SVE wells at SWMU B-3 under RL83 was completed November 2003. Testing on the B3-VEW-19-UGR borehole was performed to measure contaminant levels in soil gas and relative formation tightness using a packer sampling system. Groundwater within the open borehole at B-3 VEW-19-UGR was unable to be collected by disposable bailer in sufficient volume for sampling. The packer testing data confirmed the lithologic borehole descriptions that indicated the limestone formation throughout the 280-foot borehole depth was mostly competent, with few signs of faulting. Based on tightness testing three upper zones were identified that appeared to exhibit the greatest permeability (15-25 feet, 30-45 feet, and 75-85 feet). Additional intervals were also noted below 125-feet, but for the purposes of the pilot study, the screened intervals of the VEW and associated vapor monitoring points (VMPs) were set to address those in the projected treatment zone in the upper 90 feet of the formation. Construction of the SVE system was completed in December 2003, including manifolding the VEW piping from B3-VEW19 and B3-VEW20 to the blower, which was installed in an enclosure built specifically to house the blower.

SWMU B-3 Geophysical

SWMU B-3 Surface geophysical survey work was also performed during the week of January 19, 2004. This work completed under RL83 will try and locate significant geologic features, such as fault zones. The results from this work will be included in the Pilot Study Summary Report for SVE at SWMU B-3 scheduled for completion next quarter.

1. Percent Complete

The Treatability Studies task makes up approximately 10 percent of the RFI phase. The amount of effort needed to accomplish this task is not yet known because all pertinent data (e.g., analytical, physical, etc.) are not yet available. The percent complete depends on the number of sites requiring treatability studies and/or the need for a Treatability Study Program, but is currently estimated to be 38 percent complete.

2. Summary of Findings

Analytical data continue to be received from the PIMS treatability study monitoring efforts. The results will be reported in the treatability study report anticipated to be completed in March 2004.

AOC-65 SWVE System

Preliminary evaluation of recently collected data from VEWs surrounding AOC-65 showed estimate rates of removal of 15 pounds per year. The measured rate of removal from the subslab system was 339 pounds per year. The preliminary evaluation does not include three VEWs which were not producing flow due to blockage. Additional data was collected from each individual SVE well to determine mass removal from each of the four wells. All data will be presented in the annual O&M report scheduled to be submitted after six months of operation of the system and the interim treatability evaluation report to be submitted in September 2004.

SWMU B-3 Preliminary Geologic and SVE Pilot Study Investigation

Initial pilot testing was performed on the SWMU B-3 SVE system on December 23-24, 2003. Data collected during initial startup included air emission samples from the blower intake and mass removal rates from each of the two VEWs. Preliminary emission calculations suggest that the two blowers would be capable of removing 50 pounds of chlorinated hydrocarbons over one year of operation. The data will be compiled and presented in a Pilot Study Report for SWMU B-3 SVE at CSSA scheduled to be completed during Quarter 20.

3. Summary of Changes

No changes associated with the treatability studies occurred during this reporting period.

4. Summary of Contacts

Revisions to the scope of work proposed by University of Texas at San Antonio (UTSA) for characterization of contaminant migration near AOC-65 were submitted in a previous Quarter. CSSA continues to consider the studies proposed, but no plans are currently ongoing to conduct any of the proposed work during the next quarter.

5. Summary of Problems

No problems related to the PIMS treatability studies occurred during this reporting period.

6. Actions Taken to Correct Problems

No actions to correct problems were necessary during this reporting period.

7. Projected Work for the Next Quarter

Data collection and O&M at the AOC-65 and SWMU B-3 SVE systems will continue into the future.

Field scale treatability studies of PIMS for the previously sifted soil piles will continue in Quarter 20 as part of the treatability activities for the soil pile disposition assessment. Because this work is associated with the soil piles, it is included in the Interim Measures description.

SWMU B-3 SVE System

The summary report for the SVE pilot test conducted at SWMU B-3 will also be prepared during the next quarter for inclusion into the Environmental Encyclopedia.

8. Copies of Daily Reports, Inspection Reports, Data, etc.

No analytical data are submitted during this reporting period.

Task VII - Progress Reports

This task includes quarterly progress reports pertaining to the status of the RFI phase of work. This progress report is submitted as part of this task.

Completion of the quarterly progress report preparation task is partially funded. Five progress reports (December 2003 – January 2005) are funded under TO 0005.

1. Percent Complete

The Progress Reports task makes up approximately 5 percent of the RFI phase. The percent complete is unknown because the number of quarterly progress reports needed is currently unknown; however, it is estimated to be approximately 14 percent complete.

2. Summary of Findings

No findings associated with the progress reports were made during this reporting period.

3. Summary of Changes

No changes associated with the progress reports occurred during this reporting period.

4. Summary of Contacts

No contacts relating to progress reports were made during this reporting period.

5. Summary of Problems

No problems relating to progress reports occurred during this reporting period.

6. Actions Taken to Correct Problems

No actions to correct problems were necessary during this reporting period.

7. Projected Work for the Next Quarter

The Progress Report for Quarter 20 will be submitted.

8. Copies of Daily Reports, Inspection Reports, Data, etc.

No daily reports, inspection reports, or data related to the Progress Reports were generated during this reporting period.

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