21st Quarter - Final 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 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 21, the RFI is approximately 43 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 on the report were received. 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 Quarter.

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 information required by the Order. Completion of this task is funded for the planned RFI tasks.

Activities this Quarter

No activities associated with the RFI WP were conducted this Quarter.

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 projects are planned. As of the end of Quarter 21, WPs currently under scope are 99 percent complete. The CSSA Environmental Encyclopedia will continue to be updated as WPs are finalized.

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 CMS. 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 included groundwater monitoring, analytical data verification and validation, closure activities at several SWMUs and AOCs, Building 90/AOC-65 investigations, SWMU B-3 SVE system, AOC-55 remediation activities, and various miscellaneous tasks.

Groundwater Monitoring

There are currently 41 drinking water, livestock, and monitoring wells at CSSA that are monitored as set out in the Data Quality Objectives (DQOs). In addition, there are four Westbay^® multi-port wells that are sampled on a monthly basis. There are 10 shallow wells and piezometers around Building 90 that are monitored in conjunction with the AOC-65 treatability investigation and recharge study.

Sampling of all on-post and selected off-post wells is conducted quarterly. Off-post wells were sampled from June 4-10, 2004. Thirty-two private and public off-post drinking water wells were sampled, including FO-17, HS-2, HS-3, I10-2, I10-4, I10-7, JW-6, JW-7, JW-8, JW-9, JW‑13, JW-14, JW-26, JW-27, 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-8, RFR-10, RFR-11 and RFR-12. The locations of these wells are shown on Attachment 1. All samples were collected from ports located near the wellhead. If necessary, ports were installed near the wellhead. 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 (1,1-DCE), bromodichloromethane, bromoform, chloroform, cis-1,2-dichloroethene (cis-1,2-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 by Parsons on July 1, 2004. Data validation and verification for these samples were initiated this quarter and Parsons’ chemists submitted these data packages to AFCEE and Portage Environmental on July 16, 2004.

During the June 2004 off-post sampling event, toggle switches were added to eight off-post private wells to facilitate the off-post sampling process. These wells included JW-8, JW-27, JW‑30, LS-5, LS-6, DOM-2, RFR-4, and I10-4. These wells have been historically difficult to sample because of their completion at the surface, so switches were added to engage the well pump. The well upgrades were performed with the permission of the well owners by representatives of Parsons and GeoProjects. The upgrade consisted of a lockable toggle switch to by-pass the existing float control or pressure switch control mechanism. The upgrade allows for samplers to simply operate the switch rather than manually override the existing system. During the site visit to well JW-8, the existing pump failed for reasons not associated with the switch installation; however, CSSA replaced the pump at no cost to the owner.

Quarterly groundwater monitoring of on-post monitoring and/or drinking water wells was performed on June 15-23, 2004. 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-MW11B-LGR, CS-MW12-BS, CS-MW12-CC, CS-MW12-LGR, CS‑MW16-CC, 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 July 12-13, 2004. Data validation for VOCs and metals was performed this quarter and Parsons’ chemists will submit these data packages to AFCEE and Portage Environmental in Quarter 22.

The Final Off-post Quarterly Groundwater Monitoring Report for March 2004 was added to Volume 5 of the Environmental Encyclopedia this quarter. The Draft March On-post Quarterly Groundwater Monitoring Report was submitted for review to CSSA and AFCEE in Quarter 21. CSSA comments were received on July 16, 2004, and responses to comments were submitted July 22, 2004. This report will be finalized and submitted in Quarter 22.

Westbay®-equipped Well Sampling Events

Formation pressures in each sample zone were profiled seven times during Quarter 21 (May 12, May 20, May 26, June 4, July 12, July 16, and July 26, 2004). A continuous datalogger system was temporarily installed in CS-WB01-LGR to study the effects of recharge with respect to response time and pressure head changes. Each of the 10 multi-layered zones are continuously measured to monitor the flux of precipitation recharge through the upper 300 feet of the Glen Rose Limestone. Continuous data logging will continue through the end of July 2004. Three rounds of sampling from the Westbay^® multi-level wells were conducted during the weeks of May 27, June 22, and July 26, 2004 from CS-WB02, CS-WB03, and CS-WB04. The datalogger installed in CS-WB01 precluded it from being sampled this quarter. There was a presence of groundwater in zones which have historically been dry. CS-WB04-LGR02 was sampled on May 12, 2004. Likewise, CS-WB02-UGR01 and –LGR-02 were also sampled for the first time on July 2, 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.

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 March 2004. No post-GAC samples had concentrations above the MCL for PCE, TCE, or cis-1,2-DCE during the March event. The next post-GAC sampling event will be conducted in September 2004.

On-Post GAC Systems

A long-term pilot study to measure the effectiveness and capacity of well CS-MW16-CC was initiated at the end of February 2004 and continued through Quarter 21. Discharge rate, drawdown, and contaminant concentrations have been monitored throughout the duration of the pilot study. The system is currently operating at approximately 12.5 gpm (18,000 gallons per day [gpd]), which is 60 percent of the permitted discharge limit. When the irrigation system is constructed, the system will provide 50 percent of the allowable daily discharge (30,000 gpd) from each point source.

Parsons operated and maintained the GAC unit, and prepared a Discharge Monitoring Report (DMR) each month to comply with TPDES permit requirements. Through June 2004, approximately 1,086,760 gallons of water containing VOCs were treated by GAC and discharged from Outfall 002 during Quarter 21.

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 21 under CSSA projects TO 0019, TO 0008, TO 0042, and TO 0058.

Seven data packages related to quarterly groundwater monitoring activities were received by Parsons during Quarter 21. These packages covered the June 2004 quarterly sampling event. Thirteen additional data packages were received related to investigation derived waste (IDW), waste characterization, and soil sampling for RFIs at various SWMUs and AOCs. Additional screening-level data packages were reviewed by Parsons’ chemists for the Westbay^® multi-port groundwater sampling. All data packages were validated and verified in accordance with specific project Data Quality Objectives (DQOs) and the CSSA QAPP. Parsons submitted data packages for TO 0008 Group H and Group I this Quarter. AFCEE chemists approved data package groups TO 0008 #29, TO 0019 #2, 5, 6, 7, 8, 9, 12, 13, 14, 15, 17, 20, 22, 24, 25, 26, & 29 during 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 64 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. To-date, closure of 19 sites has been approved by TCEQ. In addition, closure reports have been submitted for six additional sites and closure reports are currently being prepared for nineteen sites.

During Quarter 21, soil/waste investigations and/or excavations were conducted at SWMUs B-2, B-12, B-23, B-23A, B-25, B-26, B-29, B-30, B-33, DD, Building 43, AOC-38, AOC-50, AOC-54, AOC-56, and AOC-67. A brief summary of the investigation/excavation results follows:

Hydrogeologic Conceptual Site Model Preparation and Well Installation Report

A draft version of the CSSA Hydrogeologic Conceptual Site Model (HCSM) was submitted to AFCEE and CSSA for internal review on January 27, 2004. CSSA provided comments during Quarter 21 and responses to comments are currently being prepared. The Draft TO42 Well Installation Report was submitted to CSSA and AFCEE during Quarter 20. CSSA provided comments on May 28, 2004. Parsons response to comments was prepared during Quarter 21 and the final report will be produced in Quarter 22.

Building 90/AOC-65 Investigation

Under TO 0058, groundwater sampling is performed following each significant rainfall event. Groundwater samples were collected on June 10 in response to heavy rainfall on multiple days totaling more than 1.5 inches. Analytical data from the April 2004 sampling event was received during Quarter 21 and data verification was conducted. Contaminant levels measured in the wells appear to be remaining relatively consistent following moderately intensive rainfall events. Results for the June 10 sampling event were received June 17, 2004. These results indicated slight lower PCE concentrations in every piezometer and monitor well sampling following the most intensive rainfall event during the recharge study.

AOC-55 Excavation

Removal actions at AOC-55 were completed during Quarter 20. Approximately 35,000 yd³ of soil were sifted for removal of ordnance and explosive (OE) scrap material, which was demilled and sent as scrap metal for recycling. The majority of the AOC-55 waste and waste residue was disposed of as Class 2 non-hazardous waste at the Waste Management, Inc., Covel Gardens Landfill. A closure report for RRS1 closure of AOC-55 was sent to TCEQ for approval. Comments to the closure report were received July 8, 2004. A response will be submitted to TCEQ during Quarter 22.

Letters summarizing the results of the March 2004 off-post groundwater monitoring event were mailed to the owners of the off-post wells on June 4, 2004. Fact Sheet 18 was mailed to the recipients on the CSSA mailing list during Quarter 21. Draft letters to well owners and a draft Fact Sheet 19 summarizing the June 2004 groundwater monitoring laboratory results were submitted to CSSA and AFCEE for review during Quarter 21.

The CSSA website was updated with documents added to the Environmental Encyclopedia through the end of December 2003. Additional updates are pending due to impending contracting activities. The website includes CSSA’s Administrative Record as required under the Order. Parsons continued to update the internal version of the electronic encyclopedia and hard-copy by updating it with all final reports through July 2004.

Parsons personnel conducted various LAN and GIS support activities during Quarter 21. Parsons personnel provided GIS support was provided during Quarter 21, including continuous updates to GIS files, overall maintenance to GIS data. Periodic GIS support was provided to CSSA personnel on an as-needed basis. Software installations were performed in preparation to migrate to ArcGIS 9, the next version of GIS software. Updates to the SDS database were also conducted to include sampling location coordinates and other electronic data. Parsons personnel provided LAN support this Quarter, including LAN system maintenance, preparation of system diagrams, documentation for backup LAN administration and using virtual private network (VPN) for access to the CSSA LAN.

1. Percent Complete

The Facility Investigation task makes up approximately 45 percent of the RFI phase. As of the end of Quarter 21, this task is approximately 26 percent complete.

2. Summary of Findings

Groundwater Monitoring

Quarterly groundwater monitoring for both on- and off-post wells was performed at CSSA from June 7 –22, 2004. A map of the well locations sampled is provided on Attachment 1 of this report. CSSA sampled 20 private and 12 public off-post wells, 36 on-post monitoring wells, and 3 drinking water wells during Quarter 21. Results of the June 2004 groundwater monitoring event will be formally reported in the draft June 2004 Quarterly Groundwater Monitoring Reports to be submitted to CSSA and AFCEE for review and comments during Quarter 22.

Building 90/AOC-65 Investigation

Observations and data collected during the groundwater recharge study activities will be presented in the Technology Evaluation Report to be prepared under TO 0058 during Quarter 22.

RCRA Facility Investigations/Closures of SWMUs and AOCs

Findings of current investigations and closures at SWMUs and AOCs were described previously in this section. In general, excavation and subsequent sampling continues at each site until RRS1 criteria are met.

3. Summary of Changes

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

4. Summary of Contacts

Results from the March 2004 quarterly groundwater monitoring event were mailed to each off-post well owner June 4, 2004. In addition, CSSA received several letters from the TCEQ during Quarter 21. The following correspondence was submitted to and/or received from TCEQ:

	April 14, 2004 - TCEQ Notice of Violation concerning TPDES calibration records;
	May 10, 2004 - CSSA submittal of calibration records in response to TCEQ April 14, 2004 Notice of Violation letter following TPDES inspection conducted February 23, 2004;
	May 14, 2004 - CSSA self-disclosure for exceedance of monthly daily flow average limit TCEQ permit 03849;
	May 14, 2004 - CSSA response to March 25, 2004, letter regarding LPST site 101264;
	May 17, 2004 - TCEQ approval of SWMU B-8 RFI Report Addendum recommending closure methods;
	May 19, 2004 - CSSA response to TCEQ letter March 24, 2004, requesting additional information concerning the December 2003 Off-post Groundwater Monitoring Report;
	June 7, 2004 - TCEQ Compliance evaluation investigation conducted March 30, 2004 list of alleged violations;
	June 11, 2004 - TCEQ approval of the September 2003 Off-post Quarterly Groundwater Monitoring Report;
	June 11, 2004 - TCEQ approval of the September 2003 On-post Quarterly Groundwater Monitoring Report;
	June 17, 2004 - TCEQ letter requiring no further submittal or response regarding the TPDES compliance investigation conducted February 23, 2004;
	June 29, 2004 - CSSA response to TCEQ letter dated June 11, 2004, regarding April 2004 coliform sampling data;
	June 29, 2004 - CSSA response to TCEQ letter dated June 15, 2004, regarding May 2004 coliform sampling data;
	July 8, 2004 - TCEQ Request for additional information/written response to comments concerning the AOC-55 closure report; and
	July 16, 2004 - CSSA response to TCEQ letter dated June 7, 2004, regarding compliance evaluation inspection conducted March 30, 2004.

Copies of all correspondence are included in Volume 1-1 of the Environmental Encyclopedia. The TCEQ collected groundwater samples from CSSA wells CS-9, CS-10, CS-1, the CS-1 entry point, and the WWTP entry point on May 10, 2004. The TCEQ expressed its intention to analyze for perchlorates, VOCs, haloacetic acids, minerals and trihalomethanes. TCEQ results were received for all samples except perchlorates. CSSA collected independent split samples from each of the sample locations. CSSA results for the independent split samples indicated that no perchlorates were detected above the method detection limit of 0.33 µg/L.

In addition, CSSA met with TCEQ on July 1, 2004to discuss the compliance evaluation inspection (CEI) list of alleged violations that was provided to CSSA on June 7, 2004.

On July 21, 2004, CSSA met with representatives from EPA Headquarters and Region 6 to discuss the CSSA environmental programs and issues, followed by a brief tour of relevant environmental sites.

5. Summary of Problems

No significant problems were encountered during the reporting period.

6. Actions Taken to Correct Problems

No actions to correct problems necessary.

7. Projected Work for the Next Quarter

Fact Sheets

Fact Sheet 19 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 will be submitted to CSSA and AFCEE for review during Quarter 21. Fact Sheet 20 will be prepared from results of the September 2004 sampling event.

Groundwater Monitoring

Final versions of the June Groundwater Monitoring Reports for on-post and off-post will be submitted in Quarter 22. Preparation of a summary report for 2004 will be initiated, to be submitted with the December 2004 Groundwater Monitoring Report.

The next quarterly groundwater monitoring event will be conducted in September 2004. The upcoming event will include the existing CSSA drinking water and monitoring wells, approximately 30 off-post wells and seven post-GAC samples from off-post wells. 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 22. A well network optimization study or long-term monitoring optimization evaluation will be initiated in Quarter 22.

The Westbay^® wells will be profiled twice a month and sampled once per month for the foreseeable future, including Quarter 22. Monitoring frequencies may be modified based on the occurrence of significant rainfall.

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 June 2004 will be reviewed and compiled into tables for eventual use in the groundwater recharge study summary section of the Technology Evaluation Report. Additional workplans will be prepared as new contracts are funded.

SWMU and AOC RFI/Closure Reports and Planned Closure Projects

Closure work will be continued for several SWMUs and AOCs during Quarter 22. A response to the July 8, 2004, TCEQ comments concerning the closure report for AOC-55 will be submitted to TCEQ during Quarter 22. A response will also be prepared addressing TCEQ comments made to the Building 40 RFI/Closure Report.

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 is delivered to the EPA within three weeks following the submittal of each quarterly progress report.

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. Task Order 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, 20 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 closure reports currently in preparation and those submitted through Quarter 21, 20 sites are recommended for closure while the remaining sites may require future investigation and/or cleanup. Through July 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 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

Parsons continued the six-month O&M period of the AOC-65 SVE system per the O&M plan schedule through June 25, 2004. O&M consisted of twice monthly system checks to assess and document the system performance, manage water in the knock-out pot, and perform miscellaneous maintenance. Pressure measurements, flow, and contaminant flux screening levels were measured during the associated system check once per month. Data collected from the quarterly and final O&M testing performed in March and June 2004 were received during Quarter 21. These data will be included in the SVE O&M Assessment Report and Technology Evaluation Report, which will include revised estimates calculated on contaminant mass removal from the subslab and exterior SVE system. The estimated emissions were well within allow emission limits established in the Permit By Rule (PBR). The final quarterly O&M sampling event of the AOC-65 SVE system was performed on June 25, 2004, and included screening of VEWs inside Building 90.

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

AOC-65 SVE System

Preliminary evaluation of recently collected data from VEWs surrounding AOC-65 showed estimated rates of removal of 15 pounds per year. The initial measured rate of removal from the subslab system was 300 pounds per year. Sustainable rates of PCE removal measured from the subslab system were measured at approximately 100 lbs/year in December 2003. The preliminary evaluation does not include three VEWs which were not producing flow due to blockages resulting from accumulation of moisture in the piping between the affected VEWs and the manifold. Analytical data from the final O&M sampling event collected from the extraction wells and from the main emission intakes following the line clearing process indicate estimated removal rates of 10 lbs/year from the AOC‑65 SVE system and 35 lbs/year from the subslab SVE system during the quarterly sampling event. All data will be presented in the annual O&M Assessment report. Preparation of this report was initiated following completion of the 6-month O&M period in June 2004. The final sampling event was conducted on June 23, 2004. The SVE systems are continuing to be operated, but no data collection is being performed until additional (pending) funds are awarded. The annual O&M report scheduled to be submitted after six months of operation of the system and the interim treatability evaluation report will to be submitted in September 2004.

SWMU B-3 Preliminary Geologic and SVE Pilot Study Investigation

The data was compiled and presented in a Pilot Study Report for SWMU B-3 SVE submitted to CSSA on February 27, 2004. This report included results from the surface geophysical investigation conducted in February 2004 that suggest a possible anomaly related to some sort of subsurface feature (fracture, buried object, or chlorinated contaminant mass) in a portion of the SWMU B-3 site boundary, but did not positively confirm the presence or orientation of a fault near SWMU B-3.

Preliminary emission calculations suggest that the two blowers would be capable of removing more than 50 pounds of chlorinated hydrocarbons over one year of operation. The data was compiled and presented in a Pilot Study Report for SWMU B-3 SVE submitted to CSSA on February 27, 2004.

3. Summary of Changes

A Technical Interchange Meeting (TIM) was held July 14, 2004. Discussions included report content and general findings from treatability studies conducted on TO 0058 and recommendations for future work. Personnel from CSSA and Parsons attended Tim #8.

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 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

O&M of the SVE systems at AOC-65 and SWMU B-3 will begin during the next quarter upon award of new task orders that include O&M testing. Field scale treatability studies of PIMS for the previously sifted soil piles will continue in Quarter 21 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.

Additional site investigations are subject to funding in current contracts.

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

No analytical data were submitted during this reporting period. Closure work will be continued for several SWMUs and AOCs during Quarter 22.

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 18 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 22 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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