phase ii environmental investigation - DocumentCloud
AMENDMENT TO THE PHASE II ENVIRONMENTAL SITE ASSESSMENT REPORT DATED AUGUST 2013
Henry B. Gonzalez Convention Center 200 E. Market Street San Antonio, Texas
Prepared for:
Hunt-Zachry, A Joint Venture 426 N. 44th Street, Suite 410 Phoenix, Arizona 85008
Prepared by:
Geo Strata Environmental Consultants, Inc. 4718 College Park San Antonio, TX 78249
Geo Strata Project No. 824-SA-Phase II
September 2013
TABLE OF CONTENTS Letter Report ATTACHMENTS Table 7 (updated) - Critical PCL Determination- Metals Table 8 (updated) - Soil Characterization for Disposal - Metals Laboratory Analytical Reports
Phase II Environmental Site Assessment Henry B. Gonzalez Convention Center San Antonio, Texas
Geo Strata Environmental Consultants, Inc. San Antonio, Texas Page 1
LETTER REPORT SUMMARY Between July 15th and 19th, 2013, Geo Strata Environmental Consultants, Inc (Geo Strata) and subcontractor Vortex Drilling, advanced a total of 23 geoprobe soil borings as part of a Phase II Environmental Site Assessment (ESA) being performed for Hunt-Zachry, A Joint Venture (Hunt-Zachry). Hunt-Zachry has been selected by the City of San Antonio (COSA) to perform demolition of the original western portion of the Henry B. Gonzalez Convention Center (HBGCC), along with further expansion to the east of the HBGCC 2001 and Grand Hyatt Expansions, as part of the HBGCC Expansion Project. The Phase II ESA was completed to assess potential impacts to the site from a range of recognized environmental conditions (RECs) identified during a Phase I ESA, performed by Geo Strata for HuntZachry in January 2013. Results of the Phase II ESA were reported to Hunt-Zachry in a report titled “Phase II Environmental Site Assessment, Henry B. Gonzalez Convention Center” dated August 2013. Findings in the report determined heavy metals concentrations in the soil, primarily consisting of arsenic, barium, lead, mercury and selenium, exceeded State regulatory levels (as defined in the Texas Risk Reduction Program [TRRP] rules) in many of the soil samples collected from the geoprobe soil borings advanced during the Phase II ESA. Recommendations provided in the report included the following: Special handling and reuse on-site (if possible) of all soils excavated during the Expansion Project from within the Phase II study area, (with the exception of soils encountered in the vicinity of SB-25, 20- 22 foot interval), due to metals impacts exceeding regulatory levels; In the event soils cannot be reused on-site, waste characterization, manifesting and disposal offsite of all excavated soils; Disposal off-site at an approval landfill, any soils excavated from 20-22 feet in the vicinity of SB25, since barium concentrations exceeded health-based levels considered safe for construction worker exposure. WASTE CLASSIFICATION DETERMINATION To assist in determining the appropriate waste classification of the heavy metals impacted soils, Geo Strata requested additional analytical testing of the soil samples which exhibited the highest concentrations of select metals, to perform toxicity characteristic leachate procedure (TCLP) analysis by EPA SW1311/6020. TCLP analysis was not required for soils exhibiting maximum arsenic, selenium and mercury concentrations, since the range of concentrations did not exceed Class II soil disposal regulatory levels. During the initial Phase II ESA, TCLP analysis was performed for soils exhibiting the maximum barium concentrations of 9040 mg/kg; TCLP results showed the waste may be classified as Class II based on the anticipated barium concentrations. TCLP analysis was also performed for a sample exhibiting a lead concentration of 144 mg/kg; however, an additional soil sample exhibited a higher lead concentration of 156 mg/kg, and therefore further TCLP analysis was required. A summary of the TCLP analytical results was provided in the August 2013 Phase II ESA report in Appendix B, Table 8. Additional TCLP analysis was performed for the lead sample exhibiting the maximum lead concentration of 156 mg/kg; TCLP results of 0.0772 mg/L showed the waste may be classified as Class II based on the maximum anticipated lead concentrations. Table 8 has been updated and is presented as an attachment to the addendum, along with the laboratory analytical report. Phase II Environmental Site Assessment Henry B. Gonzalez Convention Center San Antonio, Texas
Geo Strata Environmental Consultants, Inc. San Antonio, Texas Page 2
TRRP REGULATORY ISSUES As mentioned in the Phase II ESA report, since maximum concentrations of select metals exceeded applicable regulatory levels, future assessment and regulatory closure activities will be required. Comparison of preliminary synthetic precipitation leaching procedure (SPLP) analytical results (EPA Method SW1312/6020) for the second highest lead concentration (144 mg/kg), and the highest barium concentration (9040 mg/kg), to the TRRP groundwater ingestion protective concentration levels (PCLs), showed SPLP results measured below the groundwater ingestion PCL. Analytical results were presented in Appendix B, Table 7 in the original Phase II ESA report. Additional SPLP analysis was performed for the highest observed arsenic concentration (SB-12g, 17.5-20 feet) of 19.1 mg/kg; lead concentration (SB-33, 2-5 feet) of 156 mg/kg; selenium concentration (SB-12g, 2-5 feet) of 8.25 mg/kg; and mercury concentration (SB-34, 0-5 feet) of 0.292 mg/kg. SPLP analytical results were compared to applicable Tier I residential PCLs, including gwSoilIng, totalSoilComb, and Texas Specific Background Concentrations to determine the applicable “critical” PCL. SPLP analytical results were substituted for the gwSoilIng (Tier 3), and in all cases became the “critical” PCL with the exception of for barium, where the totalSoilcomb became the “critical” PCL, and for lead, where previous SPLP results for the sample measuring 144 mg/kg remained the “critical” PCL. Table 7 has been updated and is presented as an attachment to the addendum, along with the laboratory analytical report.
FINAL RECOMMENDATIONS The analytical data collected during the Phase II ESA, including the TCLP analysis may be utilized in preparing waste profile documentation for the site, provided this would be acceptable to the receiving landfill. Based on the results of the analysis, it appears all of the excavated soils within the Phase II study area would be classified as a Class II waste. Since SPLP analysis failed for maximum lead concentrations of 156 mg/kg (SB-33), soils excavated between 0-5 feet in the immediate vicinity of SB-33 must be disposed off-site since they exceed the “critical” PCL. Disposal off-site at an approval landfill, any soils excavated from 20-22 feet in the vicinity of SB25, since barium concentrations exceeded health-based levels considered safe for construction worker exposure.
Phase II Environmental Site Assessment Henry B. Gonzalez Convention Center San Antonio, Texas
Geo Strata Environmental Consultants, Inc. San Antonio, Texas Page 3
Table 7. (Updated) Critical PCL Determination- Metals (Residential Land Use Scenario) HBGCC 1 of 1
Sample ID / Sample Depth (Exhibiting the Maximum Concentration)
Analyte
Analytical Result mg/Kg
SB-12g / 17.5 to 20-ft
Arsenic
19.1
5.9
5
24
0.01
SB-25 / 20 to 22-ft
Barium
9040
300
440
8100
2
SB-39a / 4 to 7.5-ft
Lead
144
15
3
500
0.015
SB-33 / 2 to 5-ft
Lead
156
15
3
500
0.015
SB-12f / 2 to 5-ft
Selenium
8.25 0.292
0.3
2.3
310
0.05
0.04
0.0078
3.6
0.002
SB-34 / 0 to 5-ft Mercury Notes: Bold = Critical PCL NR - Not Required J = Analyte detected between the MDL and RL c = Analyzed outside of holdtime Note
TX Specific TRRP TIER 1 GW Background SoilIng Concentration rPCLs (mg/kg)
Further Confirmation Samples May be Required by TCEQ
TRRP SoilComb rPCLs (mg/kg)
Total
GW
GWIng (mg/L)
SPLP Analytical Result (mg/L)
Pass/Fail - Outcome
Pass - Sample Result becomes the new Critical PCL Pass - Critical PCL = TotalSoilComb between 0 to 15-ft and 9040 0.0249 mg/kg below 15-ft Pass - Sample Result becomes the 0.00737 J new Critical PCL Fail - Recommend off-site disposal of soils within the top 50.0622 ft in the vicinity of SB-33. Pass - Sample Result becomes the 0.00258 J new Critical PCL Pass Note
Henry B. Gonzalez Convention Center 200 E. Market Street San Antonio, Texas
Prepared for:
Hunt-Zachry, A Joint Venture 426 N. 44th Street, Suite 410 Phoenix, Arizona 85008
Prepared by:
Geo Strata Environmental Consultants, Inc. 4718 College Park San Antonio, TX 78249
Geo Strata Project No. 824-SA-Phase II
September 2013
TABLE OF CONTENTS Letter Report ATTACHMENTS Table 7 (updated) - Critical PCL Determination- Metals Table 8 (updated) - Soil Characterization for Disposal - Metals Laboratory Analytical Reports
Phase II Environmental Site Assessment Henry B. Gonzalez Convention Center San Antonio, Texas
Geo Strata Environmental Consultants, Inc. San Antonio, Texas Page 1
LETTER REPORT SUMMARY Between July 15th and 19th, 2013, Geo Strata Environmental Consultants, Inc (Geo Strata) and subcontractor Vortex Drilling, advanced a total of 23 geoprobe soil borings as part of a Phase II Environmental Site Assessment (ESA) being performed for Hunt-Zachry, A Joint Venture (Hunt-Zachry). Hunt-Zachry has been selected by the City of San Antonio (COSA) to perform demolition of the original western portion of the Henry B. Gonzalez Convention Center (HBGCC), along with further expansion to the east of the HBGCC 2001 and Grand Hyatt Expansions, as part of the HBGCC Expansion Project. The Phase II ESA was completed to assess potential impacts to the site from a range of recognized environmental conditions (RECs) identified during a Phase I ESA, performed by Geo Strata for HuntZachry in January 2013. Results of the Phase II ESA were reported to Hunt-Zachry in a report titled “Phase II Environmental Site Assessment, Henry B. Gonzalez Convention Center” dated August 2013. Findings in the report determined heavy metals concentrations in the soil, primarily consisting of arsenic, barium, lead, mercury and selenium, exceeded State regulatory levels (as defined in the Texas Risk Reduction Program [TRRP] rules) in many of the soil samples collected from the geoprobe soil borings advanced during the Phase II ESA. Recommendations provided in the report included the following: Special handling and reuse on-site (if possible) of all soils excavated during the Expansion Project from within the Phase II study area, (with the exception of soils encountered in the vicinity of SB-25, 20- 22 foot interval), due to metals impacts exceeding regulatory levels; In the event soils cannot be reused on-site, waste characterization, manifesting and disposal offsite of all excavated soils; Disposal off-site at an approval landfill, any soils excavated from 20-22 feet in the vicinity of SB25, since barium concentrations exceeded health-based levels considered safe for construction worker exposure. WASTE CLASSIFICATION DETERMINATION To assist in determining the appropriate waste classification of the heavy metals impacted soils, Geo Strata requested additional analytical testing of the soil samples which exhibited the highest concentrations of select metals, to perform toxicity characteristic leachate procedure (TCLP) analysis by EPA SW1311/6020. TCLP analysis was not required for soils exhibiting maximum arsenic, selenium and mercury concentrations, since the range of concentrations did not exceed Class II soil disposal regulatory levels. During the initial Phase II ESA, TCLP analysis was performed for soils exhibiting the maximum barium concentrations of 9040 mg/kg; TCLP results showed the waste may be classified as Class II based on the anticipated barium concentrations. TCLP analysis was also performed for a sample exhibiting a lead concentration of 144 mg/kg; however, an additional soil sample exhibited a higher lead concentration of 156 mg/kg, and therefore further TCLP analysis was required. A summary of the TCLP analytical results was provided in the August 2013 Phase II ESA report in Appendix B, Table 8. Additional TCLP analysis was performed for the lead sample exhibiting the maximum lead concentration of 156 mg/kg; TCLP results of 0.0772 mg/L showed the waste may be classified as Class II based on the maximum anticipated lead concentrations. Table 8 has been updated and is presented as an attachment to the addendum, along with the laboratory analytical report. Phase II Environmental Site Assessment Henry B. Gonzalez Convention Center San Antonio, Texas
Geo Strata Environmental Consultants, Inc. San Antonio, Texas Page 2
TRRP REGULATORY ISSUES As mentioned in the Phase II ESA report, since maximum concentrations of select metals exceeded applicable regulatory levels, future assessment and regulatory closure activities will be required. Comparison of preliminary synthetic precipitation leaching procedure (SPLP) analytical results (EPA Method SW1312/6020) for the second highest lead concentration (144 mg/kg), and the highest barium concentration (9040 mg/kg), to the TRRP groundwater ingestion protective concentration levels (PCLs), showed SPLP results measured below the groundwater ingestion PCL. Analytical results were presented in Appendix B, Table 7 in the original Phase II ESA report. Additional SPLP analysis was performed for the highest observed arsenic concentration (SB-12g, 17.5-20 feet) of 19.1 mg/kg; lead concentration (SB-33, 2-5 feet) of 156 mg/kg; selenium concentration (SB-12g, 2-5 feet) of 8.25 mg/kg; and mercury concentration (SB-34, 0-5 feet) of 0.292 mg/kg. SPLP analytical results were compared to applicable Tier I residential PCLs, including gwSoilIng, totalSoilComb, and Texas Specific Background Concentrations to determine the applicable “critical” PCL. SPLP analytical results were substituted for the gwSoilIng (Tier 3), and in all cases became the “critical” PCL with the exception of for barium, where the totalSoilcomb became the “critical” PCL, and for lead, where previous SPLP results for the sample measuring 144 mg/kg remained the “critical” PCL. Table 7 has been updated and is presented as an attachment to the addendum, along with the laboratory analytical report.
FINAL RECOMMENDATIONS The analytical data collected during the Phase II ESA, including the TCLP analysis may be utilized in preparing waste profile documentation for the site, provided this would be acceptable to the receiving landfill. Based on the results of the analysis, it appears all of the excavated soils within the Phase II study area would be classified as a Class II waste. Since SPLP analysis failed for maximum lead concentrations of 156 mg/kg (SB-33), soils excavated between 0-5 feet in the immediate vicinity of SB-33 must be disposed off-site since they exceed the “critical” PCL. Disposal off-site at an approval landfill, any soils excavated from 20-22 feet in the vicinity of SB25, since barium concentrations exceeded health-based levels considered safe for construction worker exposure.
Phase II Environmental Site Assessment Henry B. Gonzalez Convention Center San Antonio, Texas
Geo Strata Environmental Consultants, Inc. San Antonio, Texas Page 3
Table 7. (Updated) Critical PCL Determination- Metals (Residential Land Use Scenario) HBGCC 1 of 1
Sample ID / Sample Depth (Exhibiting the Maximum Concentration)
Analyte
Analytical Result mg/Kg
SB-12g / 17.5 to 20-ft
Arsenic
19.1
5.9
5
24
0.01
SB-25 / 20 to 22-ft
Barium
9040
300
440
8100
2
SB-39a / 4 to 7.5-ft
Lead
144
15
3
500
0.015
SB-33 / 2 to 5-ft
Lead
156
15
3
500
0.015
SB-12f / 2 to 5-ft
Selenium
8.25 0.292
0.3
2.3
310
0.05
0.04
0.0078
3.6
0.002
SB-34 / 0 to 5-ft Mercury Notes: Bold = Critical PCL NR - Not Required J = Analyte detected between the MDL and RL c = Analyzed outside of holdtime Note
TX Specific TRRP TIER 1 GW Background SoilIng Concentration rPCLs (mg/kg)
Further Confirmation Samples May be Required by TCEQ
TRRP SoilComb rPCLs (mg/kg)
Total
GW
GWIng (mg/L)
SPLP Analytical Result (mg/L)
Pass/Fail - Outcome
Pass - Sample Result becomes the new Critical PCL Pass - Critical PCL = TotalSoilComb between 0 to 15-ft and 9040 0.0249 mg/kg below 15-ft Pass - Sample Result becomes the 0.00737 J new Critical PCL Fail - Recommend off-site disposal of soils within the top 50.0622 ft in the vicinity of SB-33. Pass - Sample Result becomes the 0.00258 J new Critical PCL Pass Note
