Objective 1:  Meet TNRCC Requirements for Site Closure

Attainment of Risk Reduction Standard Number 1: Closure/Remediation to Background

Attainment of Risk Reduction Standard 1 

Remove all hazardous and nonhazardous waste and waste residues and contaminated design and operating system components such as liners, leachate collection systems, and dikes from the unit or area of the unauthorized discharge. For remediation of media that have become contaminated by releases from a waste management unit or by other unauthorized discharge of hazardous or nonhazardous waste, the contaminated media must be removed or decontaminated to cleanup levels specified in this section (30 TAC 335.554(b) and (c)).

A geophysical survey was conducted over the majority of the site to determine if there is evidence of buried waste.  No evidence of buried waste was identified in that area of the site.  However, metal scrap and other waste was visually observed protruding from the embankment on the southwestern side of the site.  

No.  Since there is evidence that waste is buried at the site, this objective has not been attained.  

Excavate in the areas which contain buried waste.  If waste and contaminated soil are encountered, remove or remediate them.  Collect confirmation samples to verify that all waste residue has been removed.

Determine compliance with RRS1 closure requirements by comparing to background as represented by results of analyses of samples taken from media that are unaffected by waste management or industrial activities. If the practical quantitation limit (PQL) is greater than background, then the PQL rather than background shall be used as the cleanup level provided that the person satisfactorily demonstrates to the executive director that lower levels of quantitation of a contaminant are not possible (30 TAC 335.554(d)).

Contaminant concentrations were compared to second revised background levels (Parsons, February 2002) or RLs, which are equivalent to PQLs.

No.  Barium, copper, nickel, zinc, lead, and mercury were detected above their respective background limits.  DEHP and fluoranthene were also detected above their respective RLs.

See above.

Attainment of cleanup levels shall be demonstrated by collection and analysis of samples from the media of concern (30 TAC 335.554(e)).

Surface and subsurface soil samples were collected at the site and analyzed for contaminants of potential concern, including SVOCs metals, VOCs, and explosives. 

No.  See above. 

Excavate in the areas which contain buried waste.  If waste and contaminated soil are encountered, remove or remediate them.  Collect confirmation samples to verify that all waste residue has been removed.

Objective 2:  Meet Requirements of 3008(h) Order for RFI

RFI Workplan Requirements

Field Sampling (Detailed listing of methods and procedures are provided in project plans which are incorporated by reference). 

Conduct field sampling in accordance with procedures defined in the project work plan, SAP, QAPP, and HSP.

All sampling was conducted in accordance with the procedures described in the project plans.  

Yes.  

NA

Facility Investigation

Characterization of Environmental Setting - Hydrogeology (B.3.A.1)

Evaluate hydrogeologic conditions at the site. 

Shallow groundwater was not encountered during drilling at the site.  

Groundwater of the Trinity Aquifer is being addressed through the Groundwater Investigation.

NA

NA

Characterization of Environmental Setting- Soils (B.3.A.2)

Characterize soils in accordance with USCS soil classification system (B.3.A.2(a)).

Soil types at the site are based on the SCS Bexar County Soil Survey (USDA, 1991) and are described in Section 1.2.1.

Yes.

NA

Identify soil profile, including ASTM classification of soils; directional relative permeability; bulk density; particle size distribution; infiltration (field test); storage capacity; mineral content; and soil conductivity (B.3.A.2(b), (c), (d), (f), (h), (i), (j), (k))

Soil types at the site are based on the SCS Bexar County Soil Survey (USDA, 1991) and are described in Section 1.2.1.

Yes.

NA

Determine soil pH (B.3.A.2(e)).

The pH of each of the soil types evaluated as part of the background metals concentration study was determined through laboratory analysis.  According to those analyses, the pH of Brackett complex and Krum soils are 7.85 and 7.87, respectively.

Yes.

NA

Determine moisture content (B.3.A.2(g)).

The moisture content of each sample was analyzed.  Moisture content values are provided in the analytical data package.

Yes.

NA

Characterization of Environmental Setting – Surface Water and Sediment (B.3.A.3)

Characterize marshes, creeks, wetland areas, or ditches at the site.

The central portion of the site, which is a former quarry, does not drain and therefore retains water.  Depths of up to 2 feet were noted during the 1996 site investigation. 

Yes

NA

Source Characterization (B.3.B)

Identify the source area (B.3.B.1). 

A description of the source area is provided in Section 1.1.2.2.

Sampling at the site was biased toward the western portion of the site which is the area most suspected of contamination. 

Surface soil contamination was found in the western portion of the site.  Additional sampling is necessary to define the lateral and vertical extent of the source area.

Excavate in the areas which contain buried waste.  If waste and contaminated soil are encountered, remove or remediate them.  Collect confirmation samples to verify that all waste residue has been removed.

Identify the location of the unit/disposal area (B.3.B.2(a)).

The boundary of the site was reviewed during preparation of this report and adjusted, if necessary, based on observations made during the field investigation.

Unknown.  The current boundary of the site appears to include too much area on the east, and possibly not enough area to the west.

Adjust boundary of site based on results of excavation/waste removal activities.

Identify the type of unit/disposal area (B.3.B.2(b)).

The type of unit/disposal area was identified in the visual observation of waste in the field.

Yes.  We know the type of disposal at most sites based on records review, interviews with base personnel, and aerial photo review.

NA

Identify design features (B.3.A.2(c)).

Information regarding design features was obtained during the Environmental Assessment (ES, 1993) and through visual observation during the field investigation.

Yes.

NA 

Identification of past and present operating practices, period of operation, age of unit/disposal area, and method used to close the unit/disposal area (B.3.B.2(d), (e), (f), and (h)).

All known information regarding these items is provided in Section 1.1.  This information is from the Environmental Assessment (if appropriate for your site), records review, interviews, aerial photo review, and visual observations.

To the extent possible with data available.

NA

Determine general physical conditions of the site (B.3.B.2(g))

The general physical condition of the site was determined during the field investigation.  This information is presented in Section 1.1.2.1.

Yes.

NA

Identify waste characteristics, including type of waste placed in the unit, physical and chemical characteristics of the wastes, and migration and dispersal characteristics of the waste (B.3.B.3).

Records regarding historic waste disposal practices at CSSA are very limited.  All known information, derived from the Environmental Assessment (Parsons ES, 1993), records review, interviews, and visual observations at the site is provided in Section 1.1.2.2.

Yes.

NA

Contamination Characterization – Groundwater (B.3.C.1)

Characterize the vertical and horizontal extent of groundwater contamination.

Shallow groundwater was not encountered during drilling at the site.

Groundwater of the Trinity Aquifer is being addressed through the Groundwater Investigation.

NA

NA

Contamination Characterization – Soil (B.3.C.2)

Determine vertical and horizontal extent of contamination (B.3.C.2(a)).

Four soil borings were advanced on the western side of the SWMU and three samples were collected from each boring.  SVOCs and metals were detected in quantities above their respective RLs and background levels.

No.  Since the extent of contamination has not been determined. 

Following recommended waste removal activities, confirmation samples are recommended to verify that all contaminated soils have been removed.

Describe soil properties (B.3.C.2(c)).

See “Characterization of Environmental Setting – Soils” above.

Yes. 

NA

Identify the direction of contaminant movement (B.3.C.2(d)). 

No actions taken.  Since no groundwater was encountered, only soil migration pathways are considered.  However, the only significant exceedances were in surface soil at two locations.

No.

Following recommended waste removal activities, confirmation samples are recommended to verify that all contaminated soils have been removed.

Extrapolate future contaminant movement (B.3.C.2(e)).

No actions taken.  See above.

NA

See above.

Implement a soil boring investigation to determine the extent of soil contamination.  Soil gas monitoring will be performed during drilling of all borings.  Laboratory analysis of borings for contaminants of potential concern will be performed on soils at depths where either visual contamination is evident, or soil gas concentrations indicate contamination.  All boreholes shall be properly abandoned.

Four soil borings were drilled and sampled.  A PID was used during drilling to monitor soil gas vapors.  Samples collected from each boring were analyzed by a laboratory, and each borehole was properly abandoned.

Yes. 

NA 

Prepare a map of all areas included in the investigation (B.3.C.2(i)).

Figures included in this report show all areas included in the investigation.

Yes.

NA

All reporting limits should be below regulatory criteria.

RLs were approved by TNRCC on October 5, 1999.  RLs are considered RRS1 standards for all analytes except metals.  Metals were compared to the second revised background levels (Parsons, February 2002) as approved by the TNRCC.

Yes.

NA

Perform all analyses in accordance with the AFCEE QAPP.

All analyses were performed in accordance with the AFCEE QAPP and approved variances.

Yes.

NA

All data flagged with “U,” “F,” “M,” and “J” are considered usable for site characterization purposes.

Yes.

“M” flagged data are also considered usable. The matrix interference is minimal and does not significantly affect the sample results.

NA

Contaminant Characterization – Sediment and Surface Water (B.3.C.3)

Conduct a surface water and sediment investigation to characterize contamination resulting from releases at the facility 

SWMU B-12 is located approximately 1,000 feet from the Salado Creek floodplain.  In the vicinity of CSSA, Salado Creek only contains water during and shortly after heavy precipitation.  Therefore, surface water was not sampled as part of the SWMU B-12 investigation.  Sampling of sediments in association with the SWMU B-12 investigation is not warranted due to the very limited amount of contamination detected at SWMU B-12. 

Although, during the 1996 investigation there was standing water covering much of the site, for the past several years, standing water has not been observed there, presumably due to long-term drought conditions.

NA

NA

Potential Receptors (B.3.D).

Collect the information necessary to describe the human populations and environmental systems that are susceptible to contaminant exposure from the Facility. 

Information regarding receptors is provided in the Risk Assessment Technical Approach Document (Volume 1-6).  In addition, the Well Research Report identifies private groundwater users within 0.25-mile and public water suppliers within 0.5-mile of CSSA.  Potential receptors are discussed in Section 1.2.5 of this Report

Yes.

NA