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, and identify actual or potential receptors. The RFI is estimated to represent approximately 30% of the required actions at CSSA. The RFI includes a Preliminary Report (5% of RFI), RFI Work Plan (10%), Facility Investigation (45%), Investigation Analysis (10%), Treatability Studies (10%), and Progress Reports (5%). At the end of Quarter 5, the RFI is approximately 23% complete.

Task I - Preliminary Report: Description of Current Conditions

This task includes preparation of the Description of Current Conditions (DCC) Report. The DCC Report includes 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 is included in the DCC Report. CSSA’s Environmental Encyclopedia was used to meet the DCC Report submittal requirements.

Completion of this task has been fully funded (under delivery order RL74). The final DCC Report was submitted to EPA and TNRCC on August 1, 1999. No regulatory comments have been received on the report. In addition, copies of the Groundwater Investigation and Source Characterization Report (Parsons ES, June 1996), the B-20 Remedial Investigation Report (Parsons ES, June 1995), and Addendum to the B-20 Remedial Investigation Report (Parsons ES, June 1996) will be provided to the EPA and TNRCC as soon as they are available in an electronic format.

This task makes up approximately 5% of the RFI phase. This task is 100% complete.

As this was a review of known information, there were no new findings.

There are no changes associated with the Preliminary Report during this reporting period. A new SWMU was identified in July 2000 during the installation of subsurface utilities. The site is located east of Building 200 and south of the North Outer Road, and occupies the northwest corner of AOC 38. It is physically located east of the roadway into the area where Wells 2, 3, and 4 are located, and south of the Stanley Trap northern fenceline. The site is estimated to be approximately 1 acre in size. The site is clearly a SWMU and not an AOC since there is a large amount of ammunition and ordnance-related debris. Its contents consist mostly of small arms ammunition, casings, and projectiles. The location of the of the new SWMU is presented in Attachment 6, as well as a 1967 aerial photograph which depicts an area of disturbance in that location.

No contacts related to the Preliminary Report were made during this reporting period.

No problems related to the Preliminary Report during this reporting period.

No actions to correct problems necessary during this reporting period.

No work on this task is projected for next Quarter.

No daily reports, inspection reports, or data related to the DCC Report generated during this reporting period.

Task II - RFI Work Plan

The Order requires that the RFI Work Plan include a Project Management Plan, Data Collection Quality Assurance Plan, Health and Safety Plan, and Community Relations Plan (CRP). As previously agreed by EPA, CSSA’s Environmental Encyclopedia, which includes all of the information (with the exception of the CRP) required by the Order, in a unique format, will be used to fulfill this requirement.

Completion of this task has been funded for the RFI tasks that have been planned.

The "Community Interest Survey Response", a figure exhibiting the distribution area of the December 1999 community mail-out, was submitted to CSSA on May 19, 2000. This figure demonstrates the distribution area of the initial community mail-out, the location of the respondents, and the location of the respondents with significant comments. Persons with addresses not found in the Bexar County Appraisal District database as well as those persons residing in Comal and Kendall counties were not mapped in this figure.

The CSSA encyclopedia will be in a hypertext document format that will be structured like an internet web site. The encyclopedia can be placed on a CD-ROM and viewed using a web browser. The encyclopedia can also be copied to a web site server to become part of an internet/intranet web site. Trellix, the originally chosen web building tool, cannot be used due to file size limitations within Trellix. Parsons ES created a draft of a large portion of the encyclopedia for CSSA and AFCEE to comment on.

This task makes up approximately 10% of the RFI phase. As of the end of Quarter 5, this task is approximately 95% complete. The remaining 5% of this task is associated with the CSSA Encyclopedia hypertext document.

2. Summary of Findings

No new findings associated with RFI Work Plan preparation during this reporting period.

Greg Lyssy of the EPA voiced concerns regarding the proposed open borehole construction for the RL83 cluster wells. The week of May 8, 2000, a conference call was held between the EPA, AFCEE, CSSA, and Parsons ES in a roundtable format to discuss the well design and construction constraints. In preparation for the conference call, Parsons ES prepared and submitted schematics with possible design alternatives. In summary, it was decided that no more than 25 feet of aquifer thickness would be monitored at each well. Designs with respect to a limited open borehole completion (e.g., less than 25-foot open intervals with no well screens or gravel packs) were given priority consideration.

Following the conference call, Parsons ES continued work on developing a suitable well completion to meet the requirements given during the conference call. Discussions with the drilling subcontractor (GeoProjects International) raised substantial concerns regarding the limited open borehole completions. In concurrence with AFCEE and CSSA, Parsons ES recommended that a well design implementing casing, screen, and filter pack materials be used to monitor a 25-foot thickness of each formational member of the Middle Trinity aquifer.

No contacts related to the RFI Work Plan were made during this reporting period.

With respect to construction costs associated with the cluster wells, the value of the drilling subcontract has risen substantially due to several factors. The proposed costs were originally based upon 15 feet of stainless steel screen and low-carbon steel casing construction, rather than 25 feet of stainless steel screen and stainless steel casing. In addition, it has been over a year since the receipt of the drilling subcontractor drilling estimate. Therefore, upgrading the wells to a stainless steel construction with 25 feet of screen will impact the budget. In conjunction with AFCEE and CSSA, Parsons ES is evaluating options to re-allocate current funding through scope reductions of the delivery order affected.

No actions to correct problems necessary during this reporting period.

The Cluster Well work plan will be finalized in Quarter 6. Actual well installations are tentatively scheduled to begin starting October 2000.

A CD-ROM showing an example of the draft electronic encyclopedia will be available for CSSA and AFCEE comment.

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

Task III - Facility Investigation

An investigation of the facility will be conducted to A) characterize the environmental setting of the facility; B) define the source(s) of contamination; C) define the nature and extent of contamination; and D) identify actual or potential receptors. In some cases, multiple phases of investigation may be necessary. The investigation results will be used to develop and evaluate alternatives during the Corrective Measures Study. All investigation activities will be conducted in accordance with the RFI Work Plan.

Completion of this task is partially funded for the RFI tasks that are planned. Investigation of all but SWMU B-2 is funded, and investigation of all but AOCs 44- 46, 49, 51- 55, 57, 59, 60, 62- 64, and 67- 70 is funded.

During May 2000, Parsons ES submitted a cost proposal for the amended Air Education Training Command (AETC) DO5068 statement of work. This modification to the current contract included those important items identified during the February 3, 2000 Technical Interchange Meeting (TIM) with the EPA. During this phase of SOW modification, all investigative work at AOCs 35, 42, 43, and 50 has been temporarily suspended. The modifications included:

Including a geophysical survey and UXO avoidance for the AOC 50 Interim Measures excavation. The number and type of analytical samples to be collected has been increased, and will now include VOC and explosives analyses.

Increasing the number of borings at AOC 42 based upon significant geophysical anomalies encountered in November 1999. Since the types of wastes buried at this AOC have not been identified, the SOW modification also includes provisions for UXO avoidance support personnel. At the request of the EPA, the boring depths will be increased to 15 feet, and will include explosives analyses.

Due to the lack of anomalies identified at AOCs 35 and 43, the scope has been reduced to remove all subsurface investigations at these locations. Surface samples will be collected to characterize AOCs only.

By the end of this quarterly reporting period, the scope modification and funding is expected to receive final approval. Once the contract is officially amended, then work will resume with facility investigations at AOCs 35, 42, 43, and 50.

Data validation and informal technical information report (ITIR) submittals for AOC 65 were completed, and investigative reports for AOCs 36, 38, 39, and 40 were initiated.

During the week of May 1, 2000, CSSA met with representatives from Parsons ES to discuss project management issues and the development of tracking tools for the large amount of data required under the Order.

During the week of May 8, 2000, CSSA met with representatives from WPI to discuss activities that WPI has been contracted for through AFCEE. The topics of discussion included: cost-to-complete for two areas of concern, groundwater monitoring and current list of sites and their actual versus projected costs, a schedule-to-complete based on planned budgetary constraints, data validation of laboratory packages for work completed outside of Parsons ES work, review of risk assessments prepared, review of "M-flagged" data, review of fact sheets, writing public notices, updating CSSA’s community relations plan mailing list, technology evaluation of the soil vapor extraction system, an evaluation for the potential use of hydrogen injection and potassium permanganate to remediate groundwater, the use of soils from sites that are not hazardous in asphalt and the polymerization processes, meetings and miscellaneous document review.

Surface soil samples were collected at AOCs 47 and 48 as shown in the table below.

During the weeks of June 26, 2000 and July 4, 2000, CSSA’s environmental staff assisted the U.S. Army Corps of Engineers in obtaining geographical positions data to enhance CSSA’s GIS. Items to be verified and corrected included roads, potable water, waste water, selected buildings, hazardous waste activity locations and other miscellaneous tasks to spatially correct these infrastructure and compliance areas.

In mid-June, CSSA collected 11 soil samples from the east pasture berm, in the approximate area of Rifle Management Unit (RMU) 1. These samples were analyzed for total lead (method SW6010B). Results from this sampling event are considered screen level data only. The resulting concentrations of total lead are presented on the figure included in Attachment 7.

Soil sample results presented in Attachment 8 were validated and approved by AFCEE. As more data are approved, the results will be presented in future quarterly reports. These data will also be presented in the individual site investigation/closure reports for each site.

Two background metals investigations were completed, both in November 1999 (soils background study and the Glen Rose background study). An internal draft report has been prepared and will be submitted for review upon AFCEE approval of the soils background study data package. The data package for the Glen Rose background study was approved by AFCEE on March 30, 2000.

This task makes up approximately 45% of the RFI phase. As of the end of Quarter 5, this task is approximately 10% complete.

Approved soil analytical results are presented in Attachment 8. Only results which have been approved by AFCEE are described here. The Glen Rose background metal study results, although approved by AFCEE, will be included with the soils background study results. In addition, the SWMU O-1 results for VOCs and metals will be presented in a draft IM SWMU O-1 report. Analytical soil results include:

AOC 36 has been reported as a former mustard gas disposal site in 1942, and an area of elevated PCE soil gas concentrations. On May 23, 1958 all items associated with this disposal were recovered, destroyed and decontaminated by the Technical Escort Unit. In response to the presence of volatile contaminants in the soil gas, a total of 10 surface soil samples collected at AOC 36 and analyzed for VOCs. No VOCs were detected in any samples collected during the January 2000 sampling event.

A total of 60 surface soil samples collected at AOC 38 and analyzed for VOCs. AOC 38 is not known to be an area of disposal activities, but does exhibit elevated PCE and TCE soil gas concentrations. No VOCs were detected in any samples during the January 2000 sampling event.

A total of three surface soil samples collected at the AOC 56 former landfill and analyzed for VOCs, SVOCs and metals. One VOC was detected in each SS01 and SS03, and two VOCs were detected in SS02. Ten SVOCs were detected in SS01, and nine were detected in both SS02 and SS03. Metals were detected in all samples.

A total of 3 surface soil samples collected at AOC 58 (a suspected trench and fill disposal site) and analyzed for VOCs, SVOCs and metals. One VOC was detected in SS01, no VOCs were detected in SS02 and 3 VOCs were detected in SS03. One SVOC was detected in each of the samples. Metals were detected in all samples.

A total of 3 surface soil samples collected at AOC 61 (a suspected trench and fill disposal site) and analyzed for VOCs, SVOCs and metals. One VOC was detected in each of the samples. No SVOCs were detected in any of the samples. Metals were detected in all samples.

A total of 2 samples were collected from beneath the sump of a degreasing vat at AOC 65 during Quarter 4, and results were reported during Quarter 5. The samples were analyzed for volatile organic and inorganic constituents. Concentrations of tetrachloroethene ranging from 1.7 mg/kg to 3.7 mg/kg were detected in both samples. Metals were detected in all samples. Samples collected by CSSA from a soil boring outside of CSSA have not been validated or approved by AFCEE through the end of Quarter 5.

Summary results for surface soil and subsurface soil samples collected between May 2000 and July 2000 will be provided after analytical data packages have been reviewed and approved by AFCEE.

The DO5068 SOW is expected to be revised by August 2000 (Quarter 6), when work can resume at the scheduled AOCs.

No contacts related to facility investigation were made during this reporting period.

No problems related to facility investigation during this reporting period.

No actions to correct problems necessary during this reporting period.

Contract modifications are underway in preparation for the installation of the deep wells/cluster wells. The work plans are being modified to reflect construction changes reviewed and will be submitted to government entities for approval during Quarter 6.

Data packages, including analytical data from the laboratories that are flagged by Parsons ES, have been submitted for AFCEE approval. A listing of these data packages is included as Attachment 9.

Task IV - Human Health and Ecological Risk Assessment

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 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 basewide human health and ecological Conceptual Site Model (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.

The draft Conceptual Site Model and Technical Approach Document for Risk Assessment was submitted for review on March 17, 2000. Comments were received on this document from CSSA on April 5, 2000. Comments were received from AFCEE on May 30, 2000.

During this quarter, revisions of the document were initiated based on the CSSA and AFCEE comments received, and were submitted on August 10, 2000. Comments from the TNRCC and EPA will be incorporated when they are received.

This task makes up approximately 15% of the RFI phase. The amount of effort needed to accomplish this task is not yet known because analytical data are not yet available. The percent complete depends on the number of sites requiring risk assessment.

The site visit resulted in the identification of potential human and ecological receptors within and surrounding CSSA. There are numerous residential areas and private and public water wells. These will be considered in any further risk assessments that are conducted. In addition, habitats and jurisdictional wetlands were identified for consideration during any subsequent ecological risk assessments.

A technical approach for conducting risk assessments under the TRRP was proposed. This approach will evaluate a site for closure to background under the Risk Reduction Standard 1 of the Risk Reduction Rule. If it is determined that this approach is not feasible, then consideration will be given to closure under the new TRRP.

No changes associated with the Risk Assessments during this reporting period.

No contacts related to the Risk Assessments were made during this reporting period.

No problems related to the Risk Assessments during this reporting period.

No actions to correct problems necessary during this reporting period.

Responses to comments will be prepared and the Technical Approach Document revised as necessary. The approach document will be submitted as part of the Environmental Encyclopedia.

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

Task V - Investigation Analysis

This task includes preparation of an Investigation Analysis to support the selection of protection standards for CSSA. It will be submitted along with the Risk Assessment Report, and it will describe the extent of the contamination in relation to background levels indicative for the area around CSSA. If possible, background levels will be used to determine the possibility of closure under the Risk Reduction Rule Standard 1. The Investigation Analysis will also include groundwater protection standards and other relevant protection standards. The relevant protection standards will be used at sites where a Standard 1 Closure was not applicable. Due to the recent promulgation (September 23, 1999) of the Texas Risk Reduction Program (TRRP, 30 TAC §350) by the TNRCC, two options are being considered for the protection standards. One option is to base the protection standards on the Risk Reduction Rule Standard 2 Media-Specific Concentrations. The other option is to use the Protective Concentration Limits developed under TRRP. The decision will be made as additional information becomes available.

This task makes up approximately 10% of the RFI phase. It was not active during Quarter 5; however during Quarter 6 it is anticipated that comparison of investigation results to closure criteria will commence.

Task VI - Treatability Studies

This task may include a Treatability Study Program, if so directed by EPA. Treatability studies are performed to determine the applicability of corrective measure technologies to conditions or problems at or resulting from waste management activities at CSSA. Where it is determined by EPA that treatability testing is necessary, candidate technologies will be identified, a treatability study Work Plan will be prepared, the treatability study(ies) will be implemented, and a treatability study report will be prepared.

Completion of this task is partially funded. Currently planned and funded (under RL33) is completion of a treatability study report for SWMU B-20, and continued operations and maintenance of the soil vapor extraction (SVE) system at SWMU B-3 (under RL74 and RL83).

As part of the Task II Interim/Stabilization Measures, a treatability study for stabilization of the excavated soils was continued during Quarter 5. The Environmental Security Technology Certification Program (ESTCP) and UFA Ventures, Inc. are demonstrating a stabilization process using Phosphate Induced Metal Stabilization (PIMS) on soils contaminated with lead and other metals. The PIMS laboratory benchscale treatability studies were completed during Quarter 5. It is anticipated that a field scale treatability study will be initiated during the next reporting period.

SVE laboratory and field data were collected in accordance with the SVE operations and monitoring (O&M) schedule detailed in the Soil Vapor Extraction Test Work Plan, Second Addendum (December 1999). The results of this testing were evaluated as part of the interim O&M Report provided to CSSA and AFCEE on July 26, 2000 for review.

The week of May 1, 2000, CSSA provided assistance to Parsons ES in balancing airflow activities at SWMU B-3. Parsons ES is routinely monitoring the facility to ensure that the system stays balanced.

The 5-month soil gas and emission samples were collected from SWMU B-3 on June 20-21, 2000 and shipped to the laboratory for analytical testing. CSSA also provided oversight to the system maintenance. Field measurement results indicate that monitoring point MP-A is over 2,000 parts per billion for total hydrocarbons. Field measurements, analytical results, and removal rates are included as tables in Attachment 10.

The final Soil Stabilization/Solidification Treatability Study Report and the final Soil Washing Treatability Study Report for SWMU B-20 were submitted in May 2000.

AFCEE and WPI comments on the draft Phytoremediation Treatability Study Report are currently being incorporated into the final.

This task makes up approximately 10% of the RFI phase. The amount of effort needed to accomplish this task is not yet known because analytical data 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.

UFA Ventures recently completed a bench-scale treatability study on a small sample of B-20 sifted soils. On average, the soils contained about 2,000 mg/kg lead. Three leaching tests were run on the soil: one with rainwater, one using TCLP methodology, and one using SPLP methodology. The TCLP extraction moved the most (between 2 and 30 ppm) lead into solution. These three leaching tests were also run on soil mixed with apatite. TCLP extract results on the soil mixed with apatite were an order of magnitude lower. UFA Ventures will document results of their bench-scale treatability study during Quarter 6.

Findings associated with the B-3 SVE O&M are provided in the draft O&M report. The testing activities demonstrated that SVE continues to be an effective mechanism for removal of VOC contamination present in the trench. An estimated 100 additional pounds of VOCs were removed during the first 5 months of O&M under this task. Some of the removal concentrations increased more than tenfold, suggesting each these VEW had widened its radius of influence. The primary mechanism for this expansion of influence is not known, but decreasing moisture contents in the subsurface soils are suspected to be an important factor.

The following recommendations are provided for the final 6 months of SVE O&M to improve contaminant removal efficiencies, and to gather some additional data to gain a better understanding of how the system is affected by climatological changes:

Flow rate at the main exhaust should be maintained at or above 60 cfm, and should be kept as constant as possible for the remainder of the O&M period.

The flow control valves at VEW-07 and VEW-18 should be shut down, and the VEWs removed from the extraction system in anticipation of the planned groundwater percolation study planned for the second half of the O&M period. These VEWs were selected because they have historically contributed some of the lowest TVH removal rates in the entire system. A Hermit data logger will record water level data in the two VEWs on a 30-minute cycle, and will be down-loaded during every bi-weekly system check until at least one week of wet weather that produces accumulation of over one foot of water in the trench has been experienced.

Meteorological data will be obtained from the CSSA weather station located at Well 16, and evaluated to assess the possible impact that precipitation and temperature may have on TVH removal and flow rates. This data may also be useful in interpreting the infiltration rate into the trench during and following rainfall events.

Findings associated with the Soil Washing and Stabilization Treatability Studies are presented in the reports that are included in Volume 4 of the encyclopedia. In general, results of the soil washing techniques performed at B-20 indicate that the physical treatment step of the soil washing process produces significant reductions in the lead concentrations in the soil composite samples. However, the treatment technique results only in recovery of the larger particulate lead fractions within the soil matrix. Therefore, this remediation process must be used in conjunction with another technique in order to recover small particulate and ionic lead fractions to reach cleanup standards. Parsons ES recommends that the technology be combined with other appropriate technologies in order to test the viability of density treatment with other remedial technologies.

Resulting solidification and stabilization efforts for SWMU B-32 and B-33 were successful in treating lead contaminated soils to maximum containment level (MCL) requirements. TCLP lead results for the solidification and stabilization for B-32 and B-33 were non-detects. The soils from SWMU B-20 small arms disposal areas were not successfully treated to action levels. TCLP results from the solidification and stabilization effort ranged from 236 mg/l to 376 mg/l. Appropriate curing times are required to achieve MCL requirements for off-site disposal of soils within a municipal landfill.

Cure times are critical in reducing the leaching of contaminants in solidified/stabilized samples. While the initial effort of solidification and stabilization at B-32 and B-33 resulted in higher TCLP lead concentrations than the untreated soils, samples taken from the additional solidification and stabilization effort with an extended cure time were below the method detection limit (MDL) and considered non-detects. The cure time was approximately 3 days for the first solidification and stabilization effort and 20 days for the second effort. The pattern of insufficient cure time adversely affecting the TCLP lead results is also noticed in the B-20 stabilization samples. Both stabilization efforts of B-20 soils had a cure time of less than 3 days. As with the B-32 and B-33 samples, the TCLP lead for these samples was higher than for the untreated sample. While analyses for B-20 samples with longer cure times are not available, it may be concluded that additional cure times will reduce lead contaminant leaching. Thus, given that sufficient cure times are provided for samples, solidification and stabilization is an effective method for treating soils.

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

No contacts related to the treatability studies were made during this reporting period.

No problems related to the O&M activities at SWMU B-3 or the B-20 treatability studies during this reporting period.

No actions to correct problems necessary during this reporting period.

The SVE unit at SWMU B-3 will remain on a bi-weekly system check schedule. Data validation and evaluation will be initiated upon receipt of analytical data from the 5-month emissions sampling event (performed June 20-21, 2000).

Finalize Phytoremediation Treatability Study Report and PIMS.

Copies of the bi-weekly SVE monitoring record are included in Attachment 10. No other daily reports, inspection reports, or data related to the treatability studies were generated 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 this task is partially funded. Progress reports for two years (August 1999 – May 2001) are funded (RL83).

This task makes up approximately 5% of the RFI phase. The percent complete is unknown because the number of treatability studies necessary is currently unknown.

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

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

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

No problems related to the Progress Reports during this reporting period.

No actions to correct problems necessary during this reporting period.

Progress Report for Quarter 6 will be submitted.

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

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