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TIM #5 Meeting Minutes
Treatability Study for Area of Concern (AOC)-65
Camp Stanley Storage Activity
F41624-00-D-8024/Task Order 0058
Parsons 740999.02000

Date: December 19, 2002

Time: 9:00 A.M. - 2:00 P.M.

Place: Camp Stanley Storage Activity (CSSA)

Subject:  TIM #5 to discuss preliminary results of the soil gas treatability study; discuss the University of Texas at San Antonio's (UTSA's) research and tracer test proposals; review project Data Quality Objectives (DQOs) for the AOC-65 Treatability Study; and, discuss the results of Parsons' assessment of borehole flowmeters. 





Brian K. Murphy, CSP


(210) 698-5208

Jeff Aston


(210) 295-7451

Chris Beal

Portage Environmental

(210) 295-7417

Dr. Enos Innis*


(210) 458-7926



(512) 719-6059

Gary Cobb**


(512) 719-6011

* Dr. Innis was present only for the portion of the meeting pertaining to UTSA. 

** Minutes prepared by Gary Cobb, Parsons.

These meeting minutes are organized in the order discussed.

Preliminary Results of Soil Gas Treatability Study at AOC-65

The meeting was opened with a discussion of the current status of the soil gas treatability study at AOC-65.  In November 2002, Parsons initiated the startup and testing of the Building 90 Subslab Soil Vapor Extraction (SVE) system and the AOC-65 SVE system and preliminary results were discussed.  Participants in this portion of the meeting included CSSA, USACE, Portage Environmental, and Parsons. 

On December 3, 2002, Parsons performed the startup and testing of the Building 90 Subslab SVE and AOC-65 SVE systems.  Prior to the startup of the system blowers, soil gas concentrations at SVE monitoring points for the two SVE systems were measured using a photoionization detector (PID) meter and an oxygen/carbon dioxide meter.  The soil gas concentrations were measured to determine subsurface conditions prior to initiating the extraction tests.  Soil gas concentrations, pressure readings and airflow rates were measured from the systems following initiation of the startup tests.  

For the AOC-65 SVE system, soil gas was extracted from vapor extraction well (VEW)-19 for the startup test and pressure responses were measured in vapor monitor points (VMPs) 1 - 5.  The AOC-65 SVE startup test was terminated prematurely after only four hours of operation due to water drawing up to block the entire screened interval in the extraction well which caused the blower to overheat and automatically shut down.  During the abbreviated startup test, the pressure readings in shallow zone and deep zones of VMP-4A (4-10’), VMP-4B (41’), and VMP-3 (38-48’), the closest monitoring points to extraction well VEW-19 (with effective screened interval of 10-15’ below ground surface [bgs]), did not exhibit significant responses suggesting little interconnection between the extraction zone and these monitoring zones.  The pressure readings from these monitoring points exhibited an almost instantaneous response indicating a direct vertical connection between the extraction intervals and these monitoring zones. 

Groundwater samples were collected from AOC-65 SVE extraction wells VEW-15, VEW-19, and VEW-16, and submitted to DHL for volatile organic compound (VOC) analysis (SW 8260B short list [acetone, methyl ethyl ketone, cis-1,2-dichloroethene, trans-1,2-dichloroethene, tetrachloroethene, trichloroethene, toluene, and isopropyl alcohol (tic)]).  Results of the groundwater samples identified the presence of tetrachloroethene (PCE) at concentrations ranging from 35.5 micrograms per liter (μg/L) in VEW-15 to 546 μg/L in VEW-19.  Trichloroethene (TCE) was present at concentrations ranging from 15.5 μg/L in VEW-15 to 73.3 μg/L in VEW-19.  Laboratory results of the soil gas samples collected during the startup tests have not been received.  PCE was the only contaminant detected in the sample collected from AOC-65 VEW-16 (at 37.0 μg/L).  Parsons anticipates continuing the initial system check and testing of this system in January 2003.

Startup testing of the Building 90 SVE system consisted of extracting soil gas from each of the 12 VEWs and monitoring soil gas concentrations and air flow.  During the startup test, the SVE blower operated for seven days and soil gas and airflow readings were measured periodically on December 5, 6, 9, and 11.  Results of the soil gas screening indicates that the concentrations increased with time during the initial phases (first few hours) of the test then declined steadily to concentrations significantly lower than pretest levels.  Parsons will monitor soil gas concentrations in the VEWs/VMPs to assess the rate of accumulation of vapors in the subslab material.

CSSA requested Parsons to bail the wells that have water in them.  The bailed water will be treated at the GAC unit.  The wells will be monitored to determine recharge.  If the wells do not fill up with water again, then the SVE system can continue using these wells.  If the wells recharge, research will need to be conducted to ascertain how and why the water enters the wells so readily.  Also, those wells impacted may have to be removed from the extraction system.  The accumulation of water in the AOC-65 VEWs raises a concern by CSSA that there possibly is a water leak from the water lines feeding Building 90.  CSSA is aware that there are leaks from the water distribution system and a leak at Building 90 could allow water to migrate through the impacted shallow material and contribute to the spread of groundwater contamination. 

Additionally, the automated collection of water levels in the AOC-65 piezometers using the weather station data logger experienced some difficulties during the initial month of data collection.  There appears to be problems with adjusting the water levels measured in some piezometers to a mean sea level datum.  Also, the water level data is being stored with previous days date rather than the date the measurements are collected.  Both these items appear to be problems with the program that controls the collection and storage of the data by the data logger.  Parsons will contact the vendor, Campbell Scientific, to get technical assistance with resolving the programming problems.

Review of DQOs for AOC-65 Treatability Study

CSSA has prepared draft DQOs to address shallow groundwater sampling activities conducted as part of the overall groundwater investigation at AOC-65.  During the startup testing of the SVE systems at AOC-65, groundwater was found to accumulate in the shallow extraction wells west of Building 90.  CSSA and Parsons decided to sample this shallow groundwater to assess the distribution and migration on contaminants through the shallow subsurface materials. A draft document prepared by CSSA presents suggested DQOs for the sampling of shallow groundwater from the SVE extraction wells.  Parsons will review the draft DQOs and incorporate this information into the AOC-65 DQO document for consideration and discussion at a future TIM.  TIM #6 will be scheduled for January 2003 so that the shallow groundwater DQOs can be resolved.  This will ensure that the appropriate data is obtained for CSSA use under TO 0058.

Discuss UTSA Research and Tracer Test Proposals

A discussion of the latest proposals from UTSA for conducting research and soil gas tracer tests was conducted with Dr. Ennis of UTSA.  UTSA has proposed to conduct soil gas tracer tests in the AOC-65 area to assess interconnectivity of fractures/faults in the area and to determine the optimum partial saturation level for the extracting PCE/TCE vapor from the unsaturated material around AOC-65.  Additionally, UTSA has proposed to conduct permeability and contaminant absorption studies on select rock cores collected during drilling activities around AOC-65/Building 90. 

CSSA and Parsons agreed that the decision to perform the tracer tests is premature given the limited information obtained from the SVE systems to date.  Additional data collection and evaluation is warranted to determine if the benefits offered by the tracer tests justify the proposed costs.  Dr. Bill Blanford at Louisiana State University (formerly of UTSA), who authored the UTSA proposal, was contacted in a conference call during the meeting to determine if the proposed costs of $30,000 for the tracer tests can be reduced.  Dr. Blanford indicated that reductions in the tracer test costs are not possible and that he thought the costs were justified by the information that will be gained regarding the optimum saturation levels for effective SVE operations.  Given the costs and the premature nature of the tracer tests, CSSA decided not to proceed with the current UTSA proposals.

Discussions were continued with Dr. Ennis regarding possible alternate research activities that UTSA may be able to provide.  CSSA indicated that it would like to assist UTSA with potential research studies associated with planned activities at AOC-65 and SWMU B-3, but justification of expenditures for UTSA's research may be difficult.  Dr. Ennis suggested that there may be research activities that can be conducted with little or no costs to CSSA.  Dr. Ennis will develop and submit a proposal for additional tests to CSSA.  Specifically, UTSA may request CSSA to participate in the purchase of some test equipment that could be used to perform the testing.

Evaluation of Borehole Flowmeter Options

Parsons has conducted a preliminary evaluation of borehole flowmeters that may be used to monitor groundwater flow rates and directions at specific subsurface locations near AOC-65.  Parsons obtained and reviewed several technical documents related to the evaluation of various types of borehole flowmeters.  From the technical documents, the heat-pulse flowmeters are frequently the preferred equipment for measuring groundwater flow within a borehole.  However, based on information presented in these technical documents, concerns related to the accuracy and repeatability of borehole flow measurements were identified.  Parsons will contact individuals with direct recent experience using borehole flowmeters, specifically the heat-pulse flowmeters, to determine if borehole flow measurements should be conducted and gain understanding into how to effectively perform the measurements.

Action items


Parsons will contact Campbell Scientific for technical assistance with correcting problems with the weather station data logger program.


Parsons will review the draft DQO additions prepared by CSSA for future shallow groundwater sampling from the SVE extraction wells, and incorporate the draft information into the AOC-65 DQO document as appropriate.


Dr. Ennis at UTSA will develop proposal for additional research at CSSA and submit the proposals for CSSA’s review.


Parson will conduct additional evaluations of borehole flowmeters to address concerns identified during the preliminary information assessment and determine if the use of borehole flowmeters are advisable for future AOC-65 activities.

Agenda for Technical Interchange/Progress Meeting #5
CSSA Treatability Study and Removal Action

Area of Concern 65 (Building 90)

Time:     Thursday, December 19, 2002; 09:00 am to 1:00 pm

Place:  Camp Stanley Storage Activity, Boerne, Texas, Environmental Office


            1.  Discuss preliminary results from soil gas treatability study.

            2.  Discuss and review UTSA research and tracer test proposals.

            3.  Review DQOs for Treatability Study relative to Future Investigation and Treatability activities at AOC-65 and as part of the Overall Groundwater Investigation at CSSA.

            4. Discuss borehole flowmeter assessment.

Proposed Order of Discussion

Date & Time


9:00 am – 9:45 am

Review Completed Field Activities and Data Collection for Treatability Study

           Subslab SVE system test data
           Building 90 SVE system data

9:45 am – 10:30 pm

Discuss and review UTSA research and tracer test proposals.

10:30 am – 11:15 am

Review DQOs and Possible Future Treatability Activities

11:15 am – 12:30 pm

Discuss borehole flowmeter options and assessment

12:30 pm – 1:00 pm

Lunch or Other topics