APPENDIX A Consent Order
APPENDIX B Selected Figures from Previous Reports
MRP-HA211
SPS-HA201
MIL LR OCK ROA D
WINCHESTER AVENUE
SPS-HA203/203A
MRP-HA212
MILL ROCK PARK (ROCHFORD FIELD ANNEX)
MRP-PS1 MRP-HA209
MRP-PS4
MRP-PS3
WADS WORT H STR EET
MRP-PS2
NOTE: 1. SURVEY INFORMATION PROVIDED BY AESCHILMAN LAND SURVEYING OF EAST HARTFORD, CT.
MILL ROCK PARK BOUNDARY
0
HALEY & ALDRICH TEST PIT EXCAVATED BY EQ NORTHEAST,INC., MERIDEN, CONNECTICUT ON 18 NOVEMBER 2004.
HALEY & ALDRICH MONITORING WELL INSTALLED BY SOILTESTING, INC., OXFORD, CT 9 THROUGH 23 AUGUST 2002.
XXX-HA201-MW
27892-421 E163
HALEY & ALDRICH TEST PIT EXCAVATED BY SOILTESTING, INC., OXFORD, CT ON 15 AUGUST 2002.
60
90
120
150
SCALE IN FEET
LEGEND
HALEY & ALDRICH SOIL BORING DRILLED BY SOILTESTING, INC., OXFORD, CT 9 THROUGH 23 AUGUST 2002.
30
XXX-HA201 RF-HA213G
HALEY & ALDRICH MONITORING WELL INSTALLED BY NEW ENGLAND BORING CONTRACTORS, INC., GLASTONBURY, CONNECTICUT 18 OCTOBER THROUGH 12 NOVEMBER 2004. HALEY & ALDRICH TEST BORING DRILLED BY NEW ENGLAND BORING CONTRACTORS, INC., GLASTONBURY, CONNECTICUT 18 OCTOBER THROUGH 12 NOVEMBER 2004.
GROUND PENETRATING RADAR TRAVERSE POINT SOURCE ANOMALY (DEPTHS RANGING 2-3 INCHES BELOW GROUND SURFACE) AREAS OF ANOMALIES
MILL ROCK PARK NEWHALL STREET NEIGHBORHOOD HAMDEN, CONNECTICUT
SURVEYED GROUND SURFACE CONTOUR
LOCATION OF CROSS-SECTION (SEE FIGURE 3) HALEY & ALDRICH HAND DRIVEN SAMPLE IN FALL 2004/ WINTER 2005.
PHASE II & III EXPLORATION LOCATION PLAN MILL ROCK PARK
MILL ROCK PARK BOUNDARY
U NDERGROUND E NGINEERING & E NVIRONMENTAL S
SCALE: AS SHOWN
APRIL 2005
FIGURE 2B
WADSWORTH STREET WINCHESTER AVENUE ROCHFORD FIELD
NEWHALL
MILL ROCK PARK
STREET
MRPHA208B RFHA206 RFHA207 -MW
MRPHA202 -MW
EL 47.0 55' S
RFHA121
RFHA112
RFHA111
EL 44.0 52' N
RFHA209 -MW
EARTHEN FILL
MRPHA206A MRPHA209 MRPHATP-1
EARTHEN FILL
RFHA113
EL 47.8 26' S
EL 47.8 35' S
MRPHA106
MRPHA103 -MW
MRPHA105
MRPHA107 -MW
MRPHA204 -MW
EL 50.34 39' N
EL 46.41 45' N
FILL
FILL FILL
BOE
BOE
ALLUVIAL DEPOSITS BOE
ELEVATION (FT.)
ALLUVIAL DEPOSITS
BOE
BOE BOE
BOE
GLACIAL TILL
GLACIODELTAIC DEPOSITS
GLACIODELTAIC DEPOSITS
SUBSURFACE PROFILE A-A LEGEND NOTES: NEWBURY
ROCHFORD FIELD
1. TOP OF BEDROCK ELEVATION INFERRED FROM: HAENI, F.P., AND SANDERS, J.E., 1974, CONTOUR MAP OF THE BEDROCK SURFACE, NEW HAVEN-WOODMONT QUADRANGLES, CONNECTICUT: U.S. GEOLOGIC SURVEY MISC. FIELD STUDIES MAP MF-557A.
MILL ROCK ROAD
STREET
SS-22
2. SEE FIGURES 2A, 2B AND 2C FOR LOCATION OF SUBSURFACE PROFILES.
RFHA121 RFHA115 -MW
RFHA124
SS-30
RFHA119
EXPLORATION DESIGNATION. MW INDICATES GROUNDWATER MONITORING WELL INSTALLED IN COMPLETED BOREHOLE. APPROXIMATE GROUND SURFACE ELEVATION AT EXPLORATION APPROXIMATE OFFSET FROM PROFILE BASELINE MAJOR STRATUM BOUNDARY BETWEEN DIFFERENT SOIL TYPES. DASHED WHERE INFERRED.
LITHOLOGY GRAPHICS EARTHEN FILL
RFHA112
RFHA211 -MW
RFHA110 -MW
SAMPLE LOCATION AND INTERVAL. SEE SAMPLER GRAPHIC LEGEND FOR SAMPLE TYPE AVERAGE WATER LEVEL IN MONITORING WELL (AUGUST 2002 THROUGH FEBRUARY 2005) EL 43.68 118' W
FILL
WATER LEVEL NOTED DURING OR SHORTLY AFTER DRILLING
BOTTOM OF EXPLORATION
EARTHEN FILL
FILL FILL
GLACIODELTAIC DEPOSITS
BOE
ELEVATION (FT.)
ELEVATION (FT.)
ALLUVIAL DEPOSITS
FILL CONTAINING INDUSTRIAL WASTE, MISCELLANEOUS WASTE OR DOMESTIC REFUSE ALLUVIAL DEPOSITS GLACIODELTAIC DEPOSITS
27892-421/422 D157
GLACIAL TILL
BEDROCK
ROCHFORD FIELD AND MILL ROCK PARK NEWHALL STREET NEIGHBORHOOD HAMDEN, CONNECTICUT
BEDROCK
SUBSURFACE PROFILES A-A AND B-B SUBSURFACE PROFILE B-B SCALE: AS SHOWN
APRIL 2005
FIGURE 3
BLAK E CIR CLE
2
RF-HA214 MRP-HA211
RF-HATP-7
3
RF-HA210
MIL LR OCK ROA D
2 3
2
1
1
2
3 1
RF-HA213A
RF-HA213E
RF-HA203 RF-HA213B
RF-HA213F
4
SPS-HA203/203A 1
1
MRP-HA209
2
RF-HA213G
MRP-HA212
2
RF-HA213H
3
SPS-HA201
RF-HATP-6
RF-HA206 RF-HA213C RF-HA213D
MRP-HA203
MRP-HA213
MRP-HA210 MRP-HA207A
2
2
MRP-HA207B MRP-PS1
2
3
1
MRP-HA207D MRP-PS4
MRP-HA207C MRP-HA207E MRP-PS2 MRP-PS3 MRP-HA205
2
RF-HATP-8
WINCHESTER AVENUE
NEWHALL STREET
MILL ROCK ROAD
2
2
MRP-HA208B MRP-HA206A
RF-HA213I RF-HA204
NEWB URY S TREET
1
RF-HA205
BRYD EN TE RRAC E
WADS WORT H STR EET
3
27892-421/422 E175
BRYDE N TERR A LEGEND SITE BOUNDARY
XXX-HA123-MW
XXX-HA114
HALEY & ALDRICH MONITORING WELL INSTALLED BY SOILTESTING, INC., OXFORD, CT 9 THROUGH 23 AUGUST 2002. HALEY & ALDRICH SOIL BORING DRILLED BY SOILTESTING, INC., OXFORD, CT 9 THROUGH 23 AUGUST 2002. HALEY & ALDRICH TEST PIT EXCAVATED BY SOILTESTING, INC., OXFORD, CT ON 15 AUGUST 2002.
HALEY & ALDRICH TEST PIT EXCAVATED BY EQ NORTHEAST,INC., MERIDEN, CONNECTICUT ON 18 NOVEMBER 2004.
XXX-HA201-MW
XXX-HA201 RF-HA213G
HALEY & ALDRICH MONITORING WELL INSTALLED BY NEW ENGLAND BORING CONTRACTORS, INC., GLASTONBURY, CONNECTICUT 18 OCTOBER THROUGH 12 NOVEMBER 2004. HALEY & ALDRICH TEST BORING DRILLED BY NEW ENGLAND BORING CONTRACTORS, INC., GLASTONBURY, CONNECTICUT 18 OCTOBER THROUGH 12 NOVEMBER 2004. HALEY & ALDRICH HAND DRIVEN SAMPLE IN FALL 2004/ WINTER 2005.
DEP INVESTIGATIONS CONDUCTED DECEMBER 2000 THROUGH MARCH 2001. [INVESTIGATION DEPTH RANGE=4.0 FEET TO 12.0 FEET BGS] THICKNESS OF EARTHEN FILL COVER MATERIAL CONTOUR
ROCHFORD FIELD AND MILL ROCK PARK PUBLIC PROPERTY INVESTIGATION NEWHALL STREET NEIGHBORHOOD HAMDEN, CONNECTICUT
CONTOUR MAP OF EARTHEN FILL THICKNESS AT SITE SCALE: AS SHOWN
APRIL 2005
FIGURE 4
BLAK E CIR CLE
MIDDLE OOL
RF-HA214 RF-HATP-7
MRP-HA211
RF-HA210 RF-HATP-8 SPS-HA201
RF-HATP-6
MRP-HA212
RF-HA213H
ROCHFORD FIELD
RF-HA213A
RF-HA213B RF-HA213E
RF-HA203
RF-HA213F
RF-HA213G RF-HA206
WINCHESTER AVENUE
NEWHALL STREET
MILL ROCK ROAD
MIL LR OCK ROA D
SPS-HA203/203A
RF-HA213C
MRP-HA203
MRP-HA209
MILL ROCK PARK (ROCHFORD FIELD ANNEX)
MRP-HA213
MRP-HA210 MRP-HA207A MRP-HA207B MRP-PS1 MRP-HA207C
MRP-HA207D MRP-PS4
MRP-HA207E MRP-PS2 MRP-PS3 MRP-HA205
RF-HA213D
RF-HA213I RF-HA204
NEWB URY S TREET
RF-HA205
BRYD EN TE RRAC E
WADS WORT H STR EET
MRP-HA208B MRP-HA206A
BRYDE N TE
27892-421/422 E176
HAMDEN COMMUNITY LEGEND SITE BOUNDARY
XXX-HA123-MW
XXX-HA114
HALEY & ALDRICH MONITORING WELL INSTALLED BY SOILTESTING, INC., OXFORD, CT 9 THROUGH 23 AUGUST 2002. HALEY & ALDRICH SOIL BORING DRILLED BY SOILTESTING, INC., OXFORD, CT 9 THROUGH 23 AUGUST 2002. HALEY & ALDRICH TEST PIT EXCAVATED BY SOILTESTING, INC., OXFORD, CT ON 15 AUGUST 2002.
HALEY & ALDRICH TEST PIT EXCAVATED BY EQ NORTHEAST,INC., MERIDEN, CONNECTICUT ON 18 NOVEMBER 2004.
XXX-HA201-MW
XXX-HA201 RF-HA213G
HALEY & ALDRICH MONITORING WELL INSTALLED BY NEW ENGLAND BORING CONTRACTORS, INC., GLASTONBURY, CONNECTICUT 18 OCTOBER THROUGH 12 NOVEMBER 2004. HALEY & ALDRICH TEST BORING DRILLED BY NEW ENGLAND BORING CONTRACTORS, INC., GLASTONBURY, CONNECTICUT 18 OCTOBER THROUGH 12 NOVEMBER 2004. HALEY & ALDRICH HAND DRIVEN SAMPLE IN FALL 2004/ WINTER 2005.
DEP INVESTIGATIONS CONDUCTED DECEMBER 2000 THROUGH MARCH 2001. [INVESTIGATION DEPTH RANGE=4.0 FEET TO 12.0 FEET BGS] THICKNESS OF TOTAL FILL CONTOUR
ROCHFORD FIELD AND MILL ROCK PARK PUBLIC PROPERTY INVESTIGATION NEWHALL STREET NEIGHBORHOOD HAMDEN, CONNECTICUT
CONTOUR MAP OF TOTAL FILL THICKNESS AT SITE SCALE: AS SHOWN
APRIL 2005
FIGURE 5
APPENDIX C Table X from the Preliminary Remedial Action Plan (2005)
TABLE X SUMMARY OF CONCEPTUAL REMEDIAL ALTERNATIVES MILL ROCK PARK AND ROCHFORD FIELD HAMDEN, CONNECTICUT
Page 1 of 3
Alternative 2 – Excavation to 4 ft Depth and Vegetative Cap
Alternative 1 – Complete Excavation & Vegetative Cap
Remedial Alternatives for Mill Rock Park & Rochford Field (1)(2)(3) Alternative 1A: On-site excavation and off-site landfill disposal or recycling of all soil exceeding RSR criteria, replacement of excavated material with clean fill and natural dilution and attenuation groundwater monitoring. Alternative 1B: On-site excavation and off-site disposal at the Hamden Middle School site of all soil exceeding RSR criteria, replacement of excavated material with clean fill and natural dilution and attenuation groundwater monitoring.
Advantages
Disadvantages
Both Alternatives: Complete removal of contaminated soil exceeding RSR criteria Achieves compliance with RDEC and PMC Risk of exposure to future site users minimal Allows continued recreational use of site No limits on future site use Application for Widespread Polluted Fill Variance or Alternative PMC and Groundwater Reclassification not required Long term monitoring only required until groundwater compliance achieved
Both Alternatives: Most expensive alternative Significant potential exposure risk to workers and residents during excavation (such as inhalation and ingestion from dust emissions, and noise pollution) Transportation of material presents risk of releases Truck traffic creates noise, air pollution and potential for injury Clean fill would need to be imported to the site to offset the volume of material being disposed of off site. Presence of waste material in deeper fill increases disposal cost Extensive confirmatory and characterization soil sampling required Potential for children to access work areas containing deep water-filled excavations Groundwater dewatering required
Alternative 1A: No risk of exposure to public during disposal
Alternative 1B: No disposal facility costs Lower transportation costs for disposal than Alternative 1A Less transportation-related issues than Alternative 1A
Alternative 2A: On-site excavation to a depth of 4 ft. below grade and off-site landfill disposal and/or recycling of soil exceeding RSR criteria, replacement of excavated material with clean fill, ELUR, Alternative PMC or Application for Widespread Polluted Fill Variance, Groundwater Reclassification and natural dilution and attenuation groundwater monitoring. Alternative 2B: On-site excavation to a depth of 4 ft. below grade and off-site disposal of soil exceeding RSR criteria at the Hamden Middle School site, replacement of excavated material with clean fill, ELUR, Alternative PMC or Application for Widespread Polluted Fill Variance, Groundwater Reclassification and natural dilution and attenuation groundwater monitoring.
Both Alternatives: Less expensive than removal of all material exceeding RDEC and PMC (Alternatives 1) Achieves compliance with RDEC and PMC Reclassification of groundwater would allow soil data to be compared to less stringent GB PMC GWPC would not apply Confirmatory soil sampling not required Dewatering not required Alternative 2A: Less risk of exposure to workers and public by eliminating stockpiling and placement activities at the Hamden Middle School site
Alternative 2B: No disposal facility costs Lower transportation costs for disposal than Alternative 1A Less transportation-related issues than Alternative 1A
Haley & Aldrich, Inc. G:\PROJECTS\27892 Newhall\Phase III Report\Table X - Conceptual Remedial Alternatives.doc
Opinion of Probable Costs for Mill Rock Park and Rochford Field Combined (4)(5)
Approximate Construction Duration (6)
Alternative 1A: $18.5 – $27.5 Million
Alternative 1A: 6 Months
Alternative 1B: $5.2 - $7.8 Million
Alternative 1B: 5 Months
Alternative 2A: $9.2 – $13.8 Million
Alternative 2A: 5 Months
Alternative 2B: $3.2 - $4.8 Million
Alternative 2B: 4 Months
Alternative 1A: Higher transportation and disposal costs than Alternative 1B
Alternative 1B: Potential exposure risk to workers and public during disposal, stockpiling and capping at Hamden Middle School
Both Alternatives: Long-term monitoring required Future disruptions must follow ELUR – additional costs and potential risks to human health Requires CTDEP approval of alternative criteria for PMC or Application for Widespread Polluted Fill Variance Requires CTDEP approval of alternative GW Classification Potential exposure risk to workers and residents during excavation (such as inhalation and ingestion from dust emissions, and noise pollution) Transportation of material presents risk of releases Truck traffic creates noise, air pollution and potential for injury Clean fill would need to be imported to the site to offset the volume of material being disposed of off site. Presence of waste material in fill increases disposal cost ELUR required Alternative 2A: Higher transportation and disposal costs than Alternative 2B Characterization soil sampling required for off-site disposal Alternative 2B: Potential exposure risk to workers and public during disposal, stockpiling and capping at Hamden Middle School
April 2005
TABLE X SUMMARY OF CONCEPTUAL REMEDIAL ALTERNATIVES MILL ROCK PARK AND ROCHFORD FIELD HAMDEN, CONNECTICUT
Page 2 of 3
Alternative 3 – Excavation to 2 ft Depth and Asphalt Cap
Remedial Alternatives for Mill Rock Park & Rochford Field (1)(2)(3) Alternative 3A: On-site excavation to a depth of 2 ft. below grade and off-site landfill disposal or recycling, replacement of excavated material with clean fill, placement of an asphalt cap, ELUR, Alternative PMC or Application for Widespread Polluted Fill Variance, Groundwater Reclassification and natural dilution and attenuation groundwater monitoring.
Alternative 3B: On-site excavation to a depth of 2 ft. below grade and off-site disposal at the Hamden Middle School site, replacement of excavated material with clean fill, placement of an asphalt cap, ELUR, Alternative PMC or Application for Widespread Polluted Fill Variance, Groundwater Reclassification and natural dilution and attenuation groundwater monitoring.
Advantages
Both Alternatives: Less expensive than removal of all material exceeding RDEC and PMC (Alternative 1) Less expensive than removal of all material to 4 ft. depth (Alternative 2) Less soil removal reduces duration of exposure risk to workers and public during excavation, reduces risk of releases during transportation, and reduces duration of noise, air pollution and potential for injury associated with transportation Achieves compliance with RDEC and PMC Reclassification of groundwater would allow soil data to be compared with less stringent GB PMC GWPC would not apply Confirmatory soil sampling not required Dewatering not required Most excavated material would be acceptable for landfill cover
Alternative 3A: Less risk of exposure to workers and public by eliminating stockpiling and placement activities at the Hamden Middle School site
Alternative 3B: No disposal facility costs Lower transportation costs for disposal than Alternative 1A Less transportation-related issues than Alternative 1A
Haley & Aldrich, Inc. G:\PROJECTS\27892 Newhall\Phase III Report\Table X - Conceptual Remedial Alternatives.doc
Disadvantages
Both Alternatives: Long-term monitoring required Future disruptions must follow ELUR – additional costs and potential risks to human health Requires CTDEP approval of alternative criteria for PMC or Application for Widespread Polluted Fill Variance Requires CTDEP approval of alternative GW Classification Potential exposure risk to workers and residents during excavation (such as inhalation and ingestion from dust emissions, and noise pollution) Transportation of material presents risk of releases Truck traffic creates noise, air pollution and potential for injury Clean fill would need to be imported to the site to offset the volume of material being disposed of off site. Paved surface requires installation of storm drains, additional storm water management facilities to control additional surface water runoff Paved surfaces must be routinely inspected for cracks and damage and immediately repaired Social impacts to the neighborhood from loss of green space and associated recreational activities (i.e., baseball and soccer fields) Characterization soil sampling required for off-site disposal ELUR required
Opinion of Probable Costs for Mill Rock Park and Rochford Field Combined (4)(5)
Approximate Construction Duration (6)
Alternative 3A: $8.5 – $12.7 Million
Alternative 3A: 4 Months
Alternative 3B: $3.2 - $4.8 Million
Alternative 3B: 3 Months
Alternative 3A: Higher transportation and disposal costs than Alternative 3B Alternative 3B: Potential exposure risk to workers and public during disposal, stockpiling and capping at Hamden Middle School
April 2005
TABLE X SUMMARY OF CONCEPTUAL REMEDIAL ALTERNATIVES MILL ROCK PARK AND ROCHFORD FIELD HAMDEN, CONNECTICUT
Page 3 of 3
Alternative 4 – Engineered Cap of Waste Materials with Vegetative Cover
Remedial Alternatives for Mill Rock Park & Rochford Field (1)(2)(3) Alternative 4: Installation of Engineered Control, ELUR and natural dilution and attenuation groundwater monitoring
Advantages
Least expensive Alternative, but accomplishes goal of protection of health and the environment No off-site soil removal: minimizes risk of releases during transportation, and reduces duration of noise, air pollution and potential for injury associated with transportation Minimizes duration of exposure risk to workers and public during construction Minimal imported materials which reduces costs for material purchase and transportation and reduces duration of noise, air pollution, and potential for injury associated with transportation. Achieves compliance with RDEC and PMC GWPC would not apply Confirmatory and characterization soil sampling not required Shortest time to complete Dewatering not required
Disadvantages
Long-term monitoring and maintenance of cap required Future disruptions must follow ELUR – additional costs to be born by Town for disturbances Additional costs related to protection against worker and public exposure risks in the event cap is disturbed in the future Cap requires installation of storm drains, additional storm water management facilities to control additional surface water runoff ELUR required Future site development restricted and expensive
Opinion of Probable Costs for Mill Rock Park and Rochford Field Combined (4)(5) $ 2.7 - $4.0 Million
Approximate Construction Duration (6) 2 Months
Notes 1.
Remedial Alternatives assume no remedial work at the Sewer Pump Station.
2.
Per CTDEP, Option “B” (i.e., disposal of waste material at the Hamden Middle School site) must be considered as part of the Remedial Alternatives Assessment. However, other no-cost alternatives may be identified after further evaluation and consideration by all parties involved and affected.
3.
GWPC will be addressed by groundwater reclassification and/or natural dilution and attenuation groundwater monitoring. SWPC will be addressed through natural dilution and attenuation monitoring or demonstration of point of compliance monitoring (i.e., monitoring of groundwater at down gradient locations prior to groundwater discharge to a surface water).
4.
Opinions of Probable Costs do not include cost for obtaining CTDEP RSR variances, alternative criteria or ELURs. Opinion of Probable Costs does include cost to restore existing recreational uses (i.e., playground equipment, ball field equipment, bleachers, etc.)
5.
Pursuant to Section B.1.b and c of the Consent Order, the Town of Hamden shall pay for the investigation and remediation of Mill Rock Park and the State of Connecticut is to fund the investigation and remediation of Rochford Field. However, for the purposes of this remedial alternatives assessment, these costs have been combined.
6.
Construction Duration does not include the time required to obtain CTDEP RSR variances, alternative criteria, ELURs or approval of remedial design.
Haley & Aldrich, Inc. G:\PROJECTS\27892 Newhall\Phase III Report\Table X - Conceptual Remedial Alternatives.doc
April 2005
APPENDIX D Proposed Remedial Alternative
PROPOSED REMEDIAL ALTERNATIVE, MILL ROCK PARK, HAMDEN, CONNECTICUT The following is a discussion of the rationale behind the proposed remedial alternative for Mill Rock Park. The discussion includes both a request for an alternative method for demonstrating Connecticut Department of Energy and Environmental Protection (CTDEEP) Remedial Standard Regulations (RSR) Pollutant Mobility Criteria (PMC) compliance and a request for permission to use Alternative PMC for certain compounds of concern, all while providing assurance the final remedy is protective of human health and the environment. The requests for the alternative method for demonstrating compliance and the alternative PMC have been formulated with guidance from CTDEEP. The proposed remedial alternative and associated discussions have been completed in accordance with the requirements of Consent Order No. SRD-128. Finally, the proposed approach is similar to that used and approved for the non-public properties in the Newhall Neigborhood. BACKGROUND Site Investigation Mill Rock Park is located south of Mill Rock Road, east of Winchester Avenue and west of Wadsworth Street. From 2002 through 2005, Haley & Aldrich investigated the impact of historic twentieth century filling activities on existing soil and groundwater conditions. A.
Soil: The soil investigation revealed there are several fill layers located within the limits of Mill Rock Park. Mill Rock Park is part of a larger historic landfill that includes abutting residential properties along Winchester Avenue, Bryden Terrace, and Wadsworth Street. The fill is primarily a mixture of soil, ash, glass, and ceramics. Site fill deposits are located both above and below the water table and appear to be highly permeable. The fill materials are underlain by alluvial and glacial deposits. Subsurface materials which were chemically tested contain semi-volatile organic compounds (SVOCs), extractable total petroleum hydrocarbons (ETPH), and lead at concentrations above applicable RSR PMC. Approximately 38 percent (i.e., 41 out of 108) of the samples tested exceeded PMC. Approximately 19 percent (i.e., 21 out of 108) of the samples had test results that were more than two times the PMC. Soil data are provided in Tables 1a and 1b.
B.
Groundwater: Seven groundwater monitoring wells were installed during our investigation to monitor Mill Rock Park groundwater quality. These wells were sampled a total of 49 times during an 11 round sampling period spanning August 2002 through August 2005. Test results consistently indicated that Mill Rock Park is in compliance with RSR GAA Groundwater Protection Criteria. During the course of sampling there was one anomalous sampling event at two wells where ETPH exceeded GAA Groundwater Protection Criteria. Test results also indicated that arsenic and zinc exceed Surface Water Protection Criteria (SWPC). Groundwater data are provided in Tables IVa and IVb.
Regulatory Decisions In October 2007, the CTDEEP issued their Remedy Selection Plan (Plan) for the Newhall Neighborhood. With regards to Mill Rock Park, the Plan indicates that a clean soil cap underlain by an impermeable barrier is the preferred remedial solution to bring the site into regulatory compliance. However, the CTDEEP also indicates in the Plan that remedial design may be modified on the Town-
Page 2 owned properties, as appropriate, to accommodate future reuse. On 6 July 2010, the CTDEEP approved an alternative PMC indicating that groundwater testing results can be used to evaluate Newhall Neighborhood non-public properties that exceed RSR PMC. It is our opinion that the logic presented in relevant portions of this letter is applicable to Mill Rock Park. Refer to attached letter for further details. PROPOSED REMEDIAL ALTERNATIVE Overview Filling activities were not unique to Mill Rock Park, and similar fill materials were also identified on numerous surrounding non-public properties within the Newhall Neighborhood. In addition, Mill Rock Park is part of a historic landfill that includes abutting residential properties along Winchester Avenue, Bryden Terrace, and Wadsworth Street. Fill materials which underlie these residential properties are the same as those that underlie Mill Rock Park. Because the materials depositional environment and exposure pathways at both Mill Rock Park and the non-public properties are very similar, we are respectfully requesting that a similar approach, as outlined in relevant sections of the 6 July 2010 letter noted above, be used to demonstrate compliance with Sections 221-133k-1 through 22a-133k-3 of the Regulations of Connecticut State Agencies (also referred to as the RSRs). Specifically, we request CTDEEP approval of an Alternative Method for Determining PMC Compliance (using groundwater data to demonstrate compliance) and Alternative PMC for lead and certain of the PAH compounds encountered in the Mill Rock Park fill material. Request for Alternative Method of Demonstrating PMC Compliance Although groundwater below Mill Rock Park has been classified as both GAA and GB, and allowable methods to demonstrate compliance for both areas are discussed below, we propose to consider the entire property under the more stringent classification (GA/GAA) and requirements for purposes of the compliance demonstration. Demonstration of Compliance with RSRs in the GAA Area. The RSRs provide for an alternative method of demonstrating compliance (RSR Section 22a-133k-2(d)(3)). Note that the “GA” in the quote below also includes “GAA” areas. (3) Alternative Pollutant Mobility Criteria for GA Areas. With respect to a substance occurring at a release area located in a GA area, and for which substance a pollutant mobility criterion is specified in sections 22a-133k-1 through 22a-133k-3, inclusive, of the Regulations of Connecticut State Agencies, the Commissioner may approve an alternative pollutant mobility criterion and an alternative method for determining compliance with such criterion, provided it is demonstrated to the Commissioner's satisfaction that the application of such alternative criterion at the subject release area will ensure that soil water at such release area will not exceed the ground-water protection criterion for such substance. Based on the regulations cited above as well as the precedent set forth in the CTDEEP approval letter dated 6 July 2010 for the non-public properties, we are proposing that wells MRPHA101-MW, MPR-HA201-MW, and RF-HA212-MW qualify as down gradient sentinel wells
Page 3 (Refer to Figure 2B). Groundwater data from these wells are provided in Tables IVa and IVb, and clearly demonstrate that the constituents in the fill materials have not adversely impacted groundwater conditions. Therefore no additional remediation is warranted to comply with RSRs for PMC or to protect groundwater quality. In addition, all data collected to date from these wells (with the exception of one anomalous ETPH reading at MRP-HA101-MW) meets GAA Groundwater Protection Criteria. Demonstration of Compliance with RSRs in the GB Area. The RSRs also provide for an alternative method of demonstrating compliance (RSR Section 22a-133k-2(d)(5)) (5) Alternative Pollutant Mobility Criteria for GB Areas. With respect to a substance occurring at a release area located in a GB area, and for which substance a pollutant mobility criterion is specified in sections 22a-133k-1 through 22a-133k-3, inclusive, of the Regulations of Connecticut State Agencies, the Commissioner may approve an alternative pollutant mobility criterion and an alternative method for determining compliance with such criterion at such release area, provided it is demonstrated to the Commissioner's satisfaction that the application of such criterion will ensure that soil water at the release area, after dilution with ground water derived from infiltration on the parcel, will not exceed the ground-water protection criterion for such substance. Based on the regulations cited above as well as the precedent set forth in the CTDEEP approval letter dated 6 July 2010 for the non-public properties, we are proposing that well MRP-HA202-MW qualifies as downgradient sentinel well for the GB Area (Figure 2B). Groundwater data from this well is provided in Table IVb and clearly demonstrate that the constituents in the fill materials have not adversely impacted groundwater conditions. Therefore no additional remediation is warranted to comply with RSRs for PMC or to protect groundwater quality. In addition, as discussed above, we are proposing to use the more stringent (GAA) criteria for the entire parcel; all data collected to date from this well meets GAA Groundwater Protection Criteria. Historically, fill materials have been in place for over 50 years at Mill Rock Park without an impermeable cover, allowing precipitation to percolate through these materials in the vadose zone to the underlying water table. Mill Rock Park fill deposits appear to be highly permeable and there are no existing drainage issues. As with the non-public properties in the Newhall Neighborhood, fill materials characterized at Mill Rock Park contain SVOCs, ETPH, and lead above the CTDEEP PMC. It is our opinion that the contaminants outlined above are adsorbed to the fill materials, which include ash, and are therefore not leaching into the groundwater. If, as outlined above, down gradient groundwater quality is used to demonstrate compliance with PMC and down gradient water quality meets GAA Groundwater Protection Criteria, then this approach negates the need for the impermeable barrier previously identified in the Plan. With regards to SWPC, contaminants of concern in groundwater (i.e., arsenic and zinc) were found to be in PMC compliance in all soil samples tested and therefore, an impermeable barrier is not going to improve water quality for these elements at Mill Rock Park. Request for Alternative Pollutant Mobility Criteria
Page 4 In addition to the alternative method of demonstrating compliance with PMC (discussed above), we also request CTDEEP approval of Alternative PMC for certain contaminants of concern present in the fill material at Mill Rock Park. As discussed with CTDEEP, Haley & Aldrich used statistical analysis, as allowed under the RSRs, to determine the 95 percent Upper Confidence Level (UCL) of all the waste fill data. The 95% UCL calculations were completed for various PAH compounds, ETPH and lead, compounds where one or more fill samples had exceeded numerical PMC. Results of the 95% UCL calculations are attached. The statistical calculations included data in both the GAA and GB groundwater class areas. Based on results of the 95% UCL calculations, alternative PMC are proposed for the following: Lead (leachable): 0.03 mg/L 1993 ug/kg Benzo(a)pyrene: 1547 ug/kg Benzo(a)anthracene: Benzo(b)fluoranthene: 3174 ug/kg Chrysene: 1630 ug/kg Pyrene: 4412 ug/kg These proposed alternative PMC are essentially the existing conditions at the site; these conditions have not resulted in leaching of the compounds into groundwater above GAA RSR criteria. Because the soil has been in place for many decades and these compounds have not been detected in groundwater above GAA criteria, it is appropriate that the PMC be equivalent to the concentrations of the compounds in the existing fill. Results of the 95% UCL calculations for ETPH and the remaining seven PAH compounds where one or more fill sample was detected above PMC did not exceed the numerical PMC, as such, we are not proposing alternative criteria for those compounds. Proposed Remedial Alternative We propose to install a permeable marker layer (instead of an impermeable barrier) at Mill Rock Park and request that the CTDEEP grant the Town of Hamden an alternative method based on GAA Groundwater Protection Criteria for determining and satisfying RSR PMC compliance requirements at Mill Rock Park and also request that the CTDEEP approve Alternative PMC (as outlined above) for lead and five PAH compounds (benzo(a)pyrene, benzo(a)anthracene, benzo(b)fluoranthene, chrysene and pyrene). The alternative method of determining compliance and the alternative criteria are protective of human health and the environment given that they represent existing site conditions that have not resulted in leaching of the contaminants to groundwater at concentrations above GAA criteria. The proposed remedial strategy is similar to that used at the non-public properties, areas with similar conditions to Mill Rock Park. A permeable marker layer will allow Mill Rock Park to continue to function under existing hydraulic conditions and avoid significant contributions of storm water to the existing sewer system along Mill Rock Road. CONCLUSIONS We believe that it is appropriate to use data from downgradient sentinel wells and alternative PMC to demonstrate compliance with PMC; that data show that the constituents in the soil are not leaching to the underlying groundwater. As noted above, this approach is consistent with a previously approved alternative PMC for the non-public properties in the Newhall Neighborhood and existing CTDEEP
Page 5 latitude within the RSRs. In addition, all the wells installed within Mill Rock Park have consistently yielded tests results which show compliance with CTDEEP GAA Groundwater Protection Criteria. By granting the alternate PMC to demonstrate RSR compliance, our proposed remedy will vary slightly from the remedy presented in the CTDEEP Plan. The proposed revised remedy will now include a permeable marker layer instead of an impermeable barrier at Mill Rock Park. This Plan modification will benefit the remediation of Mill Rock Park by:
Allowing the majority of the park to continue to freely drain to the subsurface without the need to connect to the existing storm water drainage system,
Reducing the construction schedule,
Lowering construction costs, and
Protecting public health and the environment.
Therefore we respectfully request, as part of the overall Mill Rock Park RAP approval, that the CTDEEP, in accordance with RSR Sections 22a-133k-2(d)(3) and 22a-133k-2(d)(5), grant the Town of Hamden approval of the proposed alternative PMC and the proposed alternative method for determining and satisfying RSR PMC compliance requirements at Mill Rock Park. Specifically, the alternative criteria for PMC compliance will be based on GAA Groundwater Protection Criteria compliance and the calculated Alternative PMC criteria and a permeable marker layer will be an acceptable remedial remedy at Mill Rock Park. Enclosures: 6 July 2010 CTDEEP Approval Letter 95% UCL Calculations
Concentration (ug/kg)
230 4700 760 100 100 100 100 100 100 100 100 100 100 360 100 100 16000 100 100 100 100 100 100 100 100 100 100 550 100 100 100 4600 2300 100 100 1300 17000 100 100 100 100 100 100 100 100 100 100 100 100 1200 4200 100 100 100 100 100 100 100 490 100 100 1900 100 100 100 100 100 100 100 100 100 100 1300 100 100 100 100 100 740 100 100 100 100 100 100 430 100 100 100 100 100 510 760 100 100 100 100 100 100
Natural log (LN) of concentration 5.44 8.46 6.63 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Carbazole
GA PMC:
1000 ug/kg
95% UCL-AM =
431.331
4.61 4.61
Maximum detected:
17000.000
5.89 4.61 4.61 9.68 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.31 4.61 4.61 4.61 8.43 7.74 4.61 4.61 7.17 9.74 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.09 8.34 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.19 4.61 4.61 7.55 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.17 4.61 4.61 4.61 4.61 4.61 6.61 4.61 4.61 4.61 4.61 4.61 4.61 6.06 4.61 4.61 4.61 4.61 4.61 6.23 6.63 4.61 4.61 4.61 4.61 4.61 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 5.109 1.165 2.370
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
420 100 1900 100 1100 3800 100 100 370 100 100 650 2100 100 100 1100 3700 100 840 1200 100 100 100 100 980 5400 3100 1000 100 550 100 100 100 560 100 100 100 910 910 1200 100 6100 100 100 100 100 100 100 100 100 570 100 100 100 100 100 2400 940 100 100 1900 8200 100 640 470 100 100 100 100 100 100 100 100 100 360 2500 100 100 100 100 100 100 790 2800 850 100 100 3900 100 100 100 100 100 100 100 100 100 100 2600
Natural log (LN) of concentration 6.04 4.61 7.55 4.61 7.00 8.24 4.61 4.61 5.91 4.61 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Indeno(1,2,3-cd)pyrene
GA PMC:
1000 ug/kg
95% UCL-AM =
864.185
6.48 7.65
Maximum detected:
8200.000
4.61 4.61 7.00 8.22 4.61 6.73 7.09 4.61 4.61 4.61 4.61 6.89 8.59 8.04 6.91 4.61 6.31 4.61 4.61 4.61 6.33 4.61 4.61 4.61 6.81 6.81 7.09 4.61 8.72 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.35 4.61 4.61 4.61 4.61 4.61 7.78 6.85 4.61 4.61 7.55 9.01 4.61 6.46 6.15 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 5.89 7.82 4.61 4.61 4.61 4.61 4.61 4.61 6.67 7.94 6.75 4.61 4.61 8.27 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.86
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 5.520 1.339 2.548
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
2200 15000 7500 2900 100 550 100 100 100 1300 100 100 100 1800 3400 2600 100 42000 100 810 100 100 100 100 1900 460 1200 100 2300 100 100 620 16000 6200 100 100 8200 59000 100 830 950 220 100 100 100 100 100 100 100 100 3500 14000 740 100 100 100 590 100 1900 14000 1800 100 100 15000 1700 100 100 800 750 100 100 1200 5100 100 100 830 430 4400 100 2300 8400 220 350 1600 100 390 1400 5000 100 100 1500 4900 100 2900 3900 800 100 100 100
Natural log (LN) of concentration 7.70 9.62 8.92 7.97 4.61 6.31 4.61 4.61 4.61 7.17 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Pyrene
GA PMC: 4000 ug/kg Proposed Alternative PMC: 4412 ug/kg 95% UCL-AM =
4,411.627
4.61 4.61
Maximum detected:
59000.000
7.50 8.13 7.86 4.61 10.65 4.61 6.70 4.61 4.61 4.61 4.61 7.55 6.13 7.09 4.61 7.74 4.61 4.61 6.43 9.68 8.73 4.61 4.61 9.01 10.99 4.61 6.72 6.86 5.39 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 8.16 9.55 6.61 4.61 4.61 4.61 6.38 4.61 7.55 9.55 7.50 4.61 4.61 9.62 7.44 4.61 4.61 6.68 6.62 4.61 4.61 7.09 8.54 4.61 4.61 6.72 6.06 8.39 4.61 7.74 9.04 5.39 5.86 7.38 4.61 5.97 7.24 8.52 4.61 4.61 7.31 8.50 4.61 7.97 8.27 6.68 4.61 4.61 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 6.218 1.798 3.063
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
1200 15000 1400 100 100 100 100 100 570 100 100 100 780 2600 1000 100 57000 100 100 100 100 100 100 100 100 720 100 1900 100 100 440 18000 7500 100 100 5100 61000 100 380 480 100 100 100 100 100 100 100 100 100 6000 15000 400 100 100 100 100 100 1000 9500 570 100 100 7000 1000 100 100 540 410 100 100 100 4500 100 100 100 100 100 100 660 5300 100 100 810 100 100 1100 4000 100 100 100 1800 100 1700 2500 440 100 100 100 100
Natural log (LN) of concentration 7.09 9.62 7.24 4.61 4.61 4.61 4.61 4.61 6.35 4.61 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Phenanthrene
GA PMC:
4000 ug/kg
95% UCL-AM =
2,188.487
4.61 6.66
Maximum detected:
61000.000
7.86 6.91 4.61 10.95 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.58 4.61 7.55 4.61 4.61 6.09 9.80 8.92 4.61 4.61 8.54 11.02 4.61 5.94 6.17 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 8.70 9.62 5.99 4.61 4.61 4.61 4.61 4.61 6.91 9.16 6.35 4.61 4.61 8.85 6.91 4.61 4.61 6.29 6.02 4.61 4.61 4.61 8.41 4.61 4.61 4.61 4.61 4.61 4.61 6.49 8.58 4.61 4.61 6.70 4.61 4.61 7.00 8.29 4.61 4.61 4.61 7.50 4.61 7.44 7.82 6.09 4.61 4.61 4.61 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 5.736 1.701 2.950
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
2300 17000 8400 3200 100 530 100 100 100 1300 100 100 100 2100 3100 2800 100 50000 100 870 100 100 100 100 1800 450 1300 100 2500 100 100 730 20000 7900 100 100 8700 71000 100 880 1000 210 100 100 100 100 100 100 100 100 5100 17000 920 100 100 100 630 100 2200 9300 1600 100 100 17000 2000 100 100 850 820 100 100 1400 6500 100 100 700 450 5800 100 2000 9500 250 380 1900 100 480 1600 6100 100 100 1800 5700 100 3400 4500 930 100 100 100
Natural log (LN) of concentration 7.74 9.74 9.04 8.07 4.61 6.27 4.61 4.61 4.61 7.17 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Fluoranthene
GA PMC:
5600 ug/kg
95% UCL-AM =
5,227.274
4.61 4.61
Maximum detected:
71000.000
7.65 8.04 7.94 4.61 10.82 4.61 6.77 4.61 4.61 4.61 4.61 7.50 6.11 7.17 4.61 7.82 4.61 4.61 6.59 9.90 8.97 4.61 4.61 9.07 11.17 4.61 6.78 6.91 5.35 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 8.54 9.74 6.82 4.61 4.61 4.61 6.45 4.61 7.70 9.14 7.38 4.61 4.61 9.74 7.60 4.61 4.61 6.75 6.71 4.61 4.61 7.24 8.78 4.61 4.61 6.55 6.11 8.67 4.61 7.60 9.16 5.52 5.94 7.55 4.61 6.17 7.38 8.72 4.61 4.61 7.50 8.65 4.61 8.13 8.41 6.84 4.61 4.61 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 6.268 1.849 3.124
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
100 100 1900 100 980 330 100 100 630 100 100 570 2100 100 100 100 6900 100 710 1000 100 100 100 100 740 4700 2300 810 100 100 100 100 100 420 100 100 100 740 760 950 100 6300 100 100 100 100 100 100 100 100 430 100 490 100 100 100 3600 1400 100 100 2400 13000 100 360 390 100 100 100 100 100 100 100 100 100 410 2800 100 100 100 100 100 100 690 2700 720 100 100 3900 100 100 100 100 100 100 100 100 2000 100 100
Natural log (LN) of concentration 4.61 4.61 7.55 4.61 6.89 5.80 4.61 4.61 6.45 4.61 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
benzo(k)fluoranthene
GA PMC:
1000 ug/kg
95% UCL-AM =
768.437
6.35 7.65
Maximum detected:
13000.000
4.61 4.61 4.61 8.84 4.61 6.57 6.91 4.61 4.61 4.61 4.61 6.61 8.46 7.74 6.70 4.61 4.61 4.61 4.61 4.61 6.04 4.61 4.61 4.61 6.61 6.63 6.86 4.61 8.75 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.06 4.61 6.19 4.61 4.61 4.61 8.19 7.24 4.61 4.61 7.78 9.47 4.61 5.89 5.97 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.02 7.94 4.61 4.61 4.61 4.61 4.61 4.61 6.54 7.90 6.58 4.61 4.61 8.27 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.60 4.61 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 5.444 1.315 2.522
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
970 430 5200 100 2400 8200 100 370 1600 100 100 1300 4500 100 100 2500 11000 100 2000 3000 680 100 100 100 1800 12000 5500 1800 100 760 100 100 100 1200 100 100 100 1800 1900 2400 100 19000 100 670 100 100 100 100 1500 450 1200 100 1200 100 100 490 10000 4000 100 100 6500 35000 100 960 840 220 100 100 100 100 100 100 100 100 1100 7600 720 100 100 430 430 100 1600 6800 1700 100 100 11000 1100 100 100 590 680 100 100 1400 6100 100 100
Natural log (LN) of concentration 6.88 6.06 8.56 4.61 7.78 9.01 4.61 5.91 7.38 4.61 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Benzo(b)fluoranthene
GA PMC: 1000 ug/kg Proposed Alternative GAPMC: 3174 ug/kg 95% UCL-AM =
3,173.283
7.17 8.41
Maximum detected:
35000.000
4.61 4.61 7.82 9.31 4.61 7.60 8.01 6.52 4.61 4.61 4.61 7.50 9.39 8.61 7.50 4.61 6.63 4.61 4.61 4.61 7.09 4.61 4.61 4.61 7.50 7.55 7.78 4.61 9.85 4.61 6.51 4.61 4.61 4.61 4.61 7.31 6.11 7.09 4.61 7.09 4.61 4.61 6.19 9.21 8.29 4.61 4.61 8.78 10.46 4.61 6.87 6.73 5.39 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.00 8.94 6.58 4.61 4.61 6.06 6.06 4.61 7.38 8.82 7.44 4.61 4.61 9.31 7.00 4.61 4.61 6.38 6.52 4.61 4.61 7.24 8.72 4.61 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 6.125 1.694 2.941
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
230 4700 760 100 100 100 100 100 100 100 100 100 100 360 100 100 16000 100 100 100 100 100 100 100 100 100 100 550 100 100 100 4600 2300 100 100 1300 17000 100 100 100 100 100 100 100 100 100 100 100 100 1200 4200 100 100 100 100 100 100 100 490 100 100 1900 100 100 100 100 100 100 100 100 100 100 1300 100 100 100 100 100 740 100 100 100 100 100 100 430 100 100 100 100 100 510 760 100 100 100 100 100 100
Natural log (LN) of concentration 5.44 8.46 6.63 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Benzo(ghi)perylene
GA PMC:
4200 ug/kg
95% UCL-AM =
431.331
4.61 4.61
Maximum detected:
17000.000
5.89 4.61 4.61 9.68 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.31 4.61 4.61 4.61 8.43 7.74 4.61 4.61 7.17 9.74 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.09 8.34 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.19 4.61 4.61 7.55 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.17 4.61 4.61 4.61 4.61 4.61 6.61 4.61 4.61 4.61 4.61 4.61 4.61 6.06 4.61 4.61 4.61 4.61 4.61 6.23 6.63 4.61 4.61 4.61 4.61 4.61 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 5.109 1.165 2.370
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
100 100 100 100 270 1100 100 100 100 100 100 100 620 100 100 100 100 100 100 100 100 100 100 100 230 1400 690 100 100 100 100 100 100 100 100 100 100 210 220 260 100 1800 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 3100 100 100 100 100 100 100 100 100 100 100 100 100 100 840 100 100 100 100 100 100 100 640 100 100 100 100 100 100 100 100 100 100 100 100 490 100 100
Natural log (LN) of concentration 4.61 4.61 4.61 4.61 5.60 7.00 4.61 4.61 4.61 4.61 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Dibenzo(a,h)anthracene
GA PMC:
1000 ug/kg
95% UCL-AM =
188.762
4.61 6.43
Maximum detected:
3100.000
4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 5.44 7.24 6.54 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 5.35 5.39 5.56 4.61 7.50 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 8.04 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.73 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.46 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 6.19 4.61 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 4.858 0.699 1.962
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
570 100 3100 100 1600 100 100 970 100 100 780 2700 100 100 100 3700 100 1500 2200 500 100 100 100 1300 8800 3800 1300 100 370 100 100 100 780 100 100 100 1200 1800 1600 100 15000 100 510 100 100 100 100 100 100 740 100 1300 100 100 350 8300 3000 100 100 4600 28000 100 550 550 100 100 100 100 100 100 100 100 100 1200 5900 500 100 100 100 100 100 1200 6300 1100 100 100 8200 870 100 100 470 470 100 100 100 100 100 2900 100
Natural log (LN) of concentration 6.35 4.61 8.04 4.61 7.38 4.61 4.61 6.88 4.61 4.61 6.66
Site info: Mill Rock Park - Hamden, CT Constituent:
Chrysene
GA PMC: 1000 ug/kg Proposed Alternative GAPMC: 1630 ug/kg 95% UCL-AM =
1,629.571
7.90 4.61
Maximum detected:
28000.000
4.61 4.61 8.22 4.61 7.31 7.70 6.21 4.61 4.61 4.61 7.17 9.08 8.24 7.17 4.61 5.91 4.61 4.61 4.61 6.66 4.61 4.61 4.61 7.09 7.50 7.38 4.61 9.62 4.61 6.23 4.61 4.61 4.61 4.61 4.61 4.61 6.61 4.61 7.17 4.61 4.61 5.86 9.02 8.01 4.61 4.61 8.43 10.24 4.61 6.31 6.31 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.09 8.68 6.21 4.61 4.61 4.61 4.61 4.61 7.09 8.75 7.00 4.61 4.61 9.01 6.77 4.61 4.61 6.15 6.15 4.61 4.61 4.61 4.61 4.61 7.97 4.61
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 5.764 1.548 2.775
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
1400 8500 4500 1500 100 580 100 100 100 920 100 100 100 1400 1600 1800 100 15000 100 530 100 100 100 100 100 340 890 880
100 100 100 100 6800 2800 100 100 4800 26000 100
720 650 100 100 100 100 100 100 100 100 100 5700 510 100 100 800
100 360 390 100 1200 6500 1400 100 100 8200 880 100 100 100 100 430 490 100 100 100 4000 100 100 750
350 3700 100 1800 6200 100 100 1100 100 100 1000 3500 100 100 1500 5000 100 1600 2300 450
Natural log (LN) of concentration 7.24 9.05 8.41 7.31 4.61 6.36 4.61 4.61 4.61 6.82 4.61
Site info: Mill Rock Park - Hamden, CT Constituent:
Benzo(a)pyrene
GA PMC: 1000 ug/kg Proposed Alternative GAPMC: 1993 ug/kg 95% UCL-AM =
1,992.099
4.61 4.61
Maximum detected:
26000.000
7.24 7.38 7.50 4.61 9.62 4.61 6.27 4.61 4.61 4.61 4.61 4.61 5.83 6.79 6.78 4.61 4.61 4.61 4.61 8.82 7.94 4.61 4.61 8.48 10.17 4.61 6.58 6.48 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 8.65 6.23 4.61 4.61 6.68 4.61 5.89 5.97 4.61 7.09 8.78 7.24 4.61 4.61 9.01 6.78 4.61 4.61 4.61 4.61 6.06 6.19 4.61 4.61 4.61 8.29 4.61 4.61 6.62 5.86 8.22 4.61 7.50 8.73 4.61 4.61 7.00 4.61 4.61 6.91 8.16 4.61 4.61 7.31 8.52 4.61 7.38 7.74 6.11
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 5.900 1.580 2.811
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (ug/kg)
Natural log (LN) of concentration
1100
7.00
8100 3700 1300 100 340 100 100 100 560
9.00 8.22 7.17 4.61 5.83 4.61 4.61 4.61 6.33
100
4.61
100
4.61
100
4.61
1100 1300
7.00 7.17
1400 100 16000 100 490 100 100 100 100 100 100 600
7.24 4.61 9.68 4.61 6.19 4.61 4.61 4.61 4.61 4.61 4.61 6.40
100 850 100 100 100 7100 3000 100 100 4200 27000 100 470 460 100 100 100 100 100 100 100 100 100 1200 5800 410 100 100 100 330 100 5700 890 1100 100 100 7400 800 100 100 360 400 100 100 100 100 100 2900 470 100 3100 100 1300 4300 100 100 850 100 100 710 2600 3200 100 100 100 100 100 100 100 1400 2000 420
4.61 6.75 4.61 4.61 4.61 8.87 8.01 4.61 4.61 8.34 10.20 4.61 6.15 6.13 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.09 8.67 6.02 4.61 4.61 4.61 5.80 4.61 8.65 6.79 7.00 4.61 4.61 8.91 6.68 4.61 4.61 5.89 5.99 4.61 4.61 4.61 4.61 4.61 7.97 6.15 4.61 8.04 4.61 7.17 8.37 4.61 4.61 6.75 4.61 4.61 6.57 7.86 8.07 4.61 4.61 4.61 4.61 4.61 4.61 4.61 7.24 7.60 6.04
Site info: Mill Rock Park - Hamden, CT Constituent:
Benzo(a)anthracene
GA PMC: 1000 ug/kg Proposed Alternative GAPMC: 1547 ug/kg 95% UCL-AM = Maximum detected:
1,546.022 27000.000
Determination and definition of varibles used in the above calculations. n: x: s: H:
99 5.752 1.527 2.751
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (mg/kg)
Natural log (LN) of concentration
25
3.22
25 190 25 390 690 25 25 100 25
3.22 5.25 3.22 5.97 6.54 3.22 3.22 4.61 3.22
25
3.22
350
5.86
2300
7.74
240 25
5.48 3.22
69 97 25 25 130 160 25 25 25 120 330 25
4.23 4.57 3.22 3.22 4.87 5.08 3.22 3.22 3.22 4.79 5.80 3.22
230 150 170 190 25 25 25 25 25 110 25 210 350 25 25 280 25 25 260 390 69 430 25 3100 25 25 25 25 25 25 25 25 25 25 330 300 910 25 25 25 25 25 25 25 25 25 25 510 1300 25 25 25 25 25 110 260 25 25 470 110 25 25 25 25 25 25 25 25 71 550
5.44 5.01 5.14 5.25 3.22 3.22 3.22 3.22 3.22 4.70 3.22 5.35 5.86 3.22 3.22 5.63 3.22 3.22 5.56 5.97 4.23 6.06 3.22 8.04 3.22 3.22 3.22 3.22 3.22 3.22 3.22 3.22 3.22 3.22 5.80 5.70 6.81 3.22 3.22 3.22 3.22 3.22 3.22 3.22 3.22 3.22 3.22 6.23 7.17 3.22 3.22 3.22 3.22 3.22 4.70 5.56 3.22 3.22 6.15 4.70 3.22 3.22 3.22 3.22 3.22 3.22 3.22 3.22 4.26 6.31
Site info: Mill Rock Park - Hamden, CT Constituent:
ETPH
GA PMC:
500 mg/kg
95% UCL-AM = Maximum detected:
192.907 3100.000
Determination and definition of varibles used in the above calculations. n: x: s: H:
97 4.119 1.279 2.489
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
Concentration (mg/L)
Natural log (LN) of concentration
0.006
-5.12
0.006 0.006 0.006 0.024 0.031 0.037 0.006 0.031 0.006
-5.12 -5.12 -5.12 -3.73 -3.47 -3.30 -5.12 -3.47 -5.12
0.006
-5.12
0.006
-5.12
0.006
-5.12
0.006 0.006
-5.12 -5.12
0.006 0.006 0.006 0.023 0.006 0.016 0.006 0.006 0.014 0.025 0.016 0.006
-5.12 -5.12 -5.12 -3.77 -5.12 -4.14 -5.12 -5.12 -4.27 -3.69 -4.14 -5.12
0.006 0.12 0.2 0.006 0.006 0.006 0.006 0.021 0.006 0.006 0.006 0.006 0.006 0.006 0.006 0.006 0.006 0.29 0.019 0.045 0.014 0.006 0.15 0.034 0.015 0.006 0.006 0.006 0.006 0.006 0.006 0.18 0.19 0.053 0.006 0.006 0.006 0.006 0.006 0.006 0.006 0.019 0.075 0.034 0.034 0.039 0.023 0.014 0.016 0.06 0.02
-5.12 -2.12 -1.61 -5.12 -5.12 -5.12 -5.12 -3.86 -5.12 -5.12 -5.12 -5.12 -5.12 -5.12 -5.12 -5.12 -5.12 -1.24 -3.96 -3.10 -4.27 -5.12 -1.90 -3.38 -4.20 -5.12 -5.12 -5.12 -5.12 -5.12 -5.12 -1.71 -1.66 -2.94 -5.12 -5.12 -5.12 -5.12 -5.12 -5.12 -5.12 -3.96 -2.59 -3.38 -3.38 -3.24 -3.77 -4.27 -4.14 -2.81 -3.91
Site info: Mill Rock Park - Hamden, CT Constituent:
Leachable Lead
GA PMC: 0.015 mg/L Proposed Alternative GAPMC: 0.03 mg/L 95% UCL-AM = Maximum detected:
0.030 0.290
Determination and definition of varibles used in the above calculations. n: x: s: H:
78 -4.368 1.066 2.319
n = number of samples x = mean of the log transformed data s = standard deviation of the transformed data H = Land's H-statistic, based upon n and s
Reference for the 95% UCL-AM equation and methodology:
USEPA Supplemental Guidance to RAGS: Calculating the Concentration Term, 1992 (Publication 9285.7-081).
