Amendment 04 - 2009 Soil Report for 2818 Area.pdf

1 September 30, 2009

September 30, 2009

Mr. David A. Retta The Heran Consulting Group 1934 Old Gallows Road Suite 350 Vienna, VA 22182

Subject: Data Report for Soil Contamination and Geotechnical Investigation in support of the Phase III and IV Hangar Construction Projects, 166th Airlift Wing, Delaware Air National Guard, New Castle, Delaware

Mr. Retta:

This letter report has been prepared to document the analytical results of soil sampling conducted on August 31 through September 2, 2009 and findings from the geotechnical investigation conducted on September 1 through 4, 2009, at the Delaware Air National Guard Base (DANG) in New Castle, Delaware.

1.0 BACKGROUND AND OBJECTIVE

This work was performed to obtain data regarding the environmental and geotechnical conditions of the subsurface soils within the footprints of the proposed maintenance support shops and corrosion control fuel cell hangar that are to be constructed in the tarmac area, just west of Building 2815 and south of Building 2819, respectively, and to determine if contamination exists in the subsurface soil beneath existing Buildings 2818 and 2819, which are slated for demolition.

The proposed maintenance support shops footprint is a 36,000 square foot area located approximately 90 feet south of Building 2805 and approximately 35 feet west of Building 2815.

The proposed corrosion control fuel cell hangar footprint is a 32,500 square foot area located immediately south of Building 2819, approximately 95 feet north of Building 2818 and approximately 30 feet west of Building 2822. Buildings 2818, 2822, 2826, and 2819 will be demolished during construction activities for the corrosion control fuel call hangar.

Soil borings were advanced to a depth of 10 feet at 34 locations within the proposed footprints of the maintenance shops and hangar construction site, and inside buildings 2818 and 2819, which are designated for demolition in an effort to determine if any impacted/contaminated soils may be encountered during the proposed construction/deconstruction activities. The location of the soil borings are presented in Figure 1. Geotechnical borings were advanced to a depth of 30 feet at eight locations and up to 80 feet at two locations to define the geotechnical conditions in the proposed building locations. The location of geotechnical borings are also presented in Figure 1.

Findings from the geotechnical investigation are presented in Appendix A.

Data Report for Soil Contamination & Geotechnical Investigation Delaware Air National Guard

2.0 FIELD TASKS PERFORMED

Thirty-five soil samples and four duplicate soil samples were collected from 34 direct push locations on August 31 through September 2, 2009. Samples from each borehole were collected using acetate liners at intervals determined by personnel in the field based on field screening criteria. Samples were analyzed for volatile organic compounds (VOCs) and total petroleum hydrocarbons-gasoline range organics/diesel range organics (TPH-GRO/DRO); all Delaware Hazardous Substances Clean-up Act (HSCA) guidelines were followed. The samples previously collected during the New Hangar Construction project on September 25 and 26, 2008 were analyzed for the same parameters. All soil samples were collected following the procedures in the Final Remedial Investigation/Feasibility Study Work Plan (Earth Tech, 2004).

Twenty of the 34 soil borings were advanced within the proposed building footprints; 12 for the maintenance support shops and eight within the corrosion control fuel cell hangar. Eight soil borings were distributed between the two buildings designated for demolition, and the remaining six were located in a proposed utility area, just west of the corrosion control fuel cell hangar location. An AECOM geologist logged all soil boring locations; this information in combination with data obtained from previous sampling activities in the proposed construction areas were used to characterize the soils within this area. Copies of the soil boring logs are presented in Appendix B.

Borings within the proposed building footprints and adjacent utility areas were spaced at approximately 60-foot intervals to gain a comprehensive assessment of the soils within the entire footprint. Boring locations in the buildings designated for demolition were placed to gain the best representation in areas that could be accessed by the sampling rig. The boring locations were marked-out with white paint and all required utility clearances were obtained prior to the commencement of activities. The proposed points did not conflict with utility mark-outs;

however, several points were moved slightly to ensure the boring was well clear of the marked utility.

Surface conditions of the proposed boring locations varied between asphalt and concrete; asphalt and concrete thicknesses were less than 12 inches and generally less than 6 inches. Up to 1 foot of subgrade material occurred beneath the asphalt/concrete.

Soil borings were advanced at 5-foot intervals utilizing a track-mounted Geoprobe® and cores were extracted using acetate liners. The cores were screened by AECOM personnel utilizing a photoionization detector (PID) in an effort to determine the presence of impacted/contaminated soil and the appropriate location to obtain representative samples of the subsurface soils. Up to two soil samples were proposed for each borehole; however, soil screening and visual observations of the samples indicated that little to no contamination existed and therefore, only one soil sample was collected in all but one borehole. The down hole lithology was logged by an AECOM geologist; the borehole logs are presented in Appendix B. Upon completion of the screening, logging, and sample collection, the remaining soils from the boring were containerized and transported to a designated disposal location. The open annulus of the borehole was filled with bentonite chips to 1-foot below ground surface. In areas where the boring occurred in asphalt, a concrete plug was installed to within 4 inches of ground surface.

Surface restoration of the boreholes consisted of the placement of asphalt patch and/or concrete patch to match existing grade.

3 September 30, 2009

All work was performed under modified Level D protection; results of field screening activities did not indicate the need to upgrade to Level C personal protective equipment (PPE).

Geotechnical soil borings were advanced at 10 locations on September 1 through 4, 2009.

Standard penetration test via split barrel sampling was conducted continuously down hole at each location. Seven Shelby Tube samples were collected from five borings at both of the proposed construction locations for soil classification and density determinations. The geotechnical report is presented in Appendix A.

All of the geotechnical soil borings were advanced within the proposed building footprints. Five geotechnical soil borings were drilled in the footprint of the proposed maintenance support shop;

four of the five were drilled to a depth of approximately 30 feet at the approximate location of the building corners, and the remaining one was drilled to a depth of 80 feet at the approximate location of the center of the building. Five geotechnical soil borings were drilled in the footprint of the proposed corrosion control fuel cell hangar; four of the five were drilled to a depth of approximately 30 feet at the approximate location of the building corners, and the remaining one was drilled to a depth of 65 feet at the approximate location of the center of the building. An AECOM geologist oversaw all the geotechnical activities.

The geotechnical boring locations were marked-out with white paint and all required utility clearances were obtained prior to the commencement of activities. The proposed points did not conflict with utility mark-outs; however, several points were moved slightly to ensure the boring was well clear of the marked utility.

Surface conditions of the proposed boring locations varied between asphalt and concrete; where concrete thicknesses were in excess of 6 inches, a rock drill (with air compressor) was used to initiate the borehole through the tarmac material (approximately 1-foot total). Rock coring was conducted at several locations.

Geotechnical borings were advanced utilizing a hollow stem auger rig. The down hole lithology was logged by an AECOM geologist; the borehole logs are presented in Appendix B. Upon completion of the sample collection, the remaining soils from the boring were placed back into the borehole. Surface restoration of the boreholes consisted of the placement of asphalt patch and/or concrete patch to match existing grade

All work was performed under modified Level D protection; results of field screening activities did not indicate the need to upgrade to Level C PPE.

4 September 30, 2009

5 September 30, 2009

3.0 SOIL SAMPLING RESULTS

Soil borings were advanced to a depth of 10 feet at 34 locations (Figure 1) within the proposed footprints of the maintenance support shops, corrosion control fuel cell hangar, utility area adjacent to the corrosion control fuel cell hangar, and within the two buildings designated for demolition to determine if any impacted/contaminated soils may be encountered during the proposed construction/demolition activities. A total of 35 soil samples and four duplicate soil samples were collected from the 34 direct push locations. Samples were analyzed for VOCs (United States Environmental Protection Agency [USEPA] Method 8260), and TPH-GRO/DRO (USEPA Method 8015B). The samples previously collected during the New Hangar Construction project on September 25 and 26, 2008 were analyzed for the same parameters. All soil samples were collected following the procedures in the Final Remedial Investigation/ Feasibility Study Work Plan (Earth Tech, 2004).

Samples were assigned identification numbers based on their location (HSB-021) and the depth at which the sample was collected (HSB021-4 for a sample collected at approximately 4 feet below ground surface). The sample identification (ID) numbers continued the sample ID protocol from previous soil sampling activities.

None of the samples collected during the direct push activities indicated the presence of any contamination exceeding the Department of Natural Resources and Environmental Control (DNREC) Unrestricted Use Criteria set forth in the Remediation Standards Guidance Under the Delaware HSCA (December 1999). During the sample collection process, no visual signs of contamination were noted by AECOM personnel. The sample ID, depth of sample, contaminant detected, analysis results, and DNREC action levels for all samples are presented in Table 1.

Two contaminants (acetone and toluene) were detected in almost all of the soil samples. All but one soil sample contained low levels of acetone at concentrations ranging from 7 to 250 micrograms per kilogram (µg/kg). Acetone is a main laboratory contaminant. Trace levels of toluene were detected in 28 of 39 samples at concentrations ranging from 0.9 to 3 µg/kg.

Other contaminants detected in soil samples include benzene at one location (0.5 µg/kg), 2-butanone at 13 locations (0.9 to 20 µg/kg), carbon disulfide at seven locations (0.9 to 20 µg/kg), cis-1,2-dichloroethene at four locations (1 to 5 µg/kg), methylene chloride at three locations (3 to 9 µg/kg), tetrachloroethane at seven locations (1 to 6 µg/kg), trichloroethene at two locations (3 to 11 µg/kg), and xylene at one location (0.9 µg/kg).

Six sample points indicated the presence of trace levels of TPH-GRO at concentrations ranging from 0.3 to 2.9 µg/kg, and 14 sample points indicated the presence of low levels of TPH-DRO at concentrations ranging from 8.5 to 180 µg/kg. The detected levels were well below the clean-up criteria of 100,000 µg/kg for both of these contaminants.

Copies of the laboratory analysis are presented in Appendix C.

6 September 30, 2009

Table 1 Soil Sampling Results

Sample

ID

Depth (ft bgs)

Acetone (µg/kg)

Benzene (µg/kg)

2-Butanone (µg/kg)

Carbon Disulfide (µg/kg) cis-1,2- Dichloro ethene (µg/kg)

Methylene Chloride (µg/kg)

Tetrachloroe thane

(µg/kg)

Toluene (µg/kg)

Trichloro ethene (µg/kg)

Xylene (µg/kg)

TPH GRO

(µg/kg)

TPH DRO

(µg/kg)

URS Delaware (µg/kg) 6,000 500 19,000 10,000 7,000 500 500 100,000 500 NA 100,000 100,000

HSB021-3 3 - 3.25 12 J ND ND ND ND ND ND ND ND ND ND ND

HSB022-9 9 - 9.5 8 J ND ND ND ND 9 ND 1 J ND ND ND ND

HSB023-3 3 - 3.5 21 ND ND ND ND ND 2 J 3 J ND ND ND ND

HSB024-4 3.5 - 4 14 J ND ND ND ND ND ND 2 J ND ND ND ND

HSB024-

4DUP 3.5 - 4 23 ND ND ND ND ND ND ND ND ND ND ND

HSB025-3 2.5 - 3 24 ND ND ND ND ND 2 J 1 J ND ND ND 13 J

HSB026-4 3.5 - 4 14 J ND ND ND ND ND ND 2 J ND ND 0.3 J 180

HSB027-7 6.25 - 6.75 ND ND ND ND ND ND ND ND ND ND ND ND

HSB028-3 2.25 - 2.75 67 ND ND ND ND 8 6 1 J 3 J ND ND ND

HSB029-3 3 - 3.25 19 J ND ND ND ND ND ND 2 J ND ND ND 16

HSB030-3 3 - 3.5 110 ND 10 ND ND ND ND ND ND ND ND 85

HSB031-3 2.75 - 3 120 ND 14 ND ND ND 1 J ND ND ND ND 12 J

HSB032-5 5 - 5.25 7 J ND ND 11 ND ND ND 0.9 J ND 0.9 J ND ND

HSB033-3 3.25 - 3.75 88 ND 10 J ND ND ND ND ND ND ND ND ND

HSB034-3 2.75 - 3.25 57 ND 6 J ND ND ND ND 2 J ND ND ND ND

HSB035-3 2.5 - 3 53 ND 6 J 2 J 2 J ND ND ND ND ND 1.7 62

HSB035-

3DUP 2.5 - 3 160 0.5 J 22 2 J 1 J ND ND 2 J ND ND 1.6 57

HSB035-5 5 - 5.5 45 ND 5 J 20 1 J ND 1 J 2 J ND ND 0.5 J ND

HSB036-3 3 - 3.25 250 ND 39 2 J 5 J ND ND 2 J ND ND ND 23

HSB037-3 3 - 3.5 64 ND 7 J 2 J ND ND ND 1 J ND ND ND 9.9 J

HSB038-3 3 - 3.5 10 J ND ND ND ND ND ND 1 J ND ND ND 16

HSB038-

3DUP 3 - 3.5 12 J ND ND ND ND ND ND 2 J ND ND ND 13

HSB039-3 2.5 - 3 56 ND 5 J ND ND ND 1 J 2 J ND ND ND 27

7 September 30, 2009

Table 1 Soil Sampling Results

Sample

ID

Depth (ft bgs)

Acetone (µg/kg)

Benzene (µg/kg)

2-Butanone (µg/kg)

Carbon Disulfide (µg/kg) cis-1,2- Dichloro ethene (µg/kg)

Methylene Chloride (µg/kg)

Tetrachloroe thane

(µg/kg)

Toluene (µg/kg)

Trichloro ethene (µg/kg)

Xylene (µg/kg)

TPH GRO

(µg/kg)

TPH DRO

(µg/kg)

URS Delaware (µg/kg) 6,000 500 19,000 10,000 7,000 500 500 100,000 500 NA 100,000 100,000

HSB040-3 2.75 - 3 110 ND 10 J ND ND ND 6 ND 11 ND ND ND

HSB041-3 2.5 - 3 46 ND 5 J 0.9 J ND ND ND 2 J ND ND 1.0 J ND

HSB042-3 2.5 - 3 27 ND ND 1 J ND ND ND 2 J ND ND 2.9 8.5 J

HSB043-3 3 - 3.5 27 ND ND ND ND 3 J ND 2 J ND ND ND ND

HSB044-5 4.5 - 5 20 J ND ND ND ND ND ND 1 J ND ND ND ND

HSB045-4 3.5 - 4.5 32 ND ND ND ND ND ND ND ND ND ND ND

HSB046-4 4 - 4.5 38 ND ND ND ND ND ND 2 J ND ND ND ND

HSB046-

4DUP 4 - 4.5 35 ND ND ND ND ND ND 1 J ND ND ND ND

HSB047-3 2.75 - 3 73 ND ND ND ND ND ND 1 J ND ND ND 26

HSB048-9 9 - 9.5 28 ND ND ND ND ND ND 1 J ND ND ND ND

HSB049-2 2.25 - 2.5 19 J ND ND ND ND ND ND 1 J ND ND ND ND

HSB050-3 2.75 - 3 40 ND ND ND ND ND ND ND ND ND ND ND

HSB051-3 3 - 3.25 29 ND ND ND ND ND ND 2 J ND ND ND ND

HSB052-3 2.75 - 3 91 ND 13 ND ND ND ND 1 J ND ND ND ND

HSB053-10 9.75 - 10 21 ND ND ND ND ND ND ND ND ND ND ND

HSB054-2 2 - 2.5 45 ND ND ND ND ND ND 2 J ND ND ND ND

Note: Acetone was detected in all but on sample ranging from 7 to 250 µg/kg; however, it is a main laboratory contaminant.

"J" indicates an estimated value “ND” = Non detect

4.0 CONCLUSIONS AND RECOMMENDATIONS

Based on visual observation and field and laboratory test results, the soil within the proposed building construction/demolition footprints did not indicate the presence of any contamination exceeding the DNREC Unrestricted Use Criteria set forth in the Remediation Standards Guidance Under the Delaware HSCA (December 1999).

Conclusions and recommendations for the geotechnical portion of this report are presented in the Subsurface Investigation and Geotechnical Engineering Report (Appendix A).

8 September 30, 2009