SUPPLEMENTAL INVESTIGATION

ADDENDUM REPORT

NON-PUBLIC PROPERTIES STUDY AREA

HAMDEN, CONNECTICUT

 

 

 

 

 

 

 

Prepared for:

 

OLIN CORPORATION

CHARLESTON, TENNESSEE

 

 

March 2006

 

 

 

 

 

 

 

 

                                                          Environmental ENGINEERS, SCIENTISTS & PLANNERS


TABLE OF CONTENTS

Section                                                                                                                        Page

 

1.0   INTRODUCTION.. 1-1

1.1      PROPERTY ACCESS. 1-2

1.2      DATA QUALITY OBJECTIVES. 1-2

2.0   SUPPLEMENTAL INVESTIGATION SCOPE OF WORK.. 2-1

2.1      CONTIGUOUS FILL ASSESSMENT. 2-2

2.2      ISOLATED FILL DELINEATION.. 2-3

2.2.1    Bare spot sampling. 2-4

2.3      GROUNDWATER INVESTIGATION.. 2-4

2.4      DATA VALIDATION.. 2-5

3.0   CONCEPTUAL SITE MODEL.. 3-1

3.1      MODIFICATIONS TO THE CONCEPTUAL SITE MODEL. 3-1

3.2      CONTIGUOUS FILL DELINEATION.. 3-1

3.2.1    Block E – Newhall Street Area. 3-2

3.2.1.1    1048 Winchester Avenue. 3-2

3.2.1.2    22 Newbury Street 3-2

3.2.2    Block J – Southwest Satellite Area. 3-2

3.2.2.1    293 and 297 Goodrich Street 3-2

3.2.2.2    300 and 304 Morse Street 3-2

3.2.3    Block L – Southwest Satellite Area. 3-2

3.2.3.1    453 Shelton Avenue. 3-2

3.2.4    Block Q – Newhall Street Area. 3-3

3.2.4.1    16 Marlboro Street 3-3

3.2.5    Block T – Augur Street Area. 3-3

3.2.5.1    331 Augur Street 3-3

3.2.5.2    13 and 17 Harris Street 3-3

3.3      AREAS OF ISOLATED FILL. 3-3

3.4      RIGHT-OF-WAY CONFIRMATION BORINGS. 3-17

3.5      ISOLATED FILL SUMMARY.. 3-19

3.6      GROUNDWATER QUALITY.. 3-21

4.0   CONCLUSIONS. 4-1

5.0   REMEDIAL ACTION PLAN.. 5-1

 


 

List of Tables - Microsoft Excel required to open and read the files.

 

2-1       Investigation Activities by Parcel (Microsoft Excel Document)

 

NOTE: Tables 3-2 through 3-10, listed below, are all in the same file, Tables 3-2 to 3-10.xls

3-2       SW Satellite Area Analytical Data Summary (Microsoft Excel Document)

3-3       Newhall Street Area Analytical Data Summary (Microsoft Excel Document)

3-5       Augur Street Area Analytical Data Summary (Microsoft Excel Document)

3-6       Isolated Fill Analytical Data Summary (Microsoft Excel Document)

3-7       Ambient Sample Analytical Data Summary (Microsoft Excel Document)

3-8       Non-compliant Samples for Only Non-Principal SOCs (Microsoft Excel Document)

3-9       Properties Outside Contiguous Fill – Rationale for Investigation (Microsoft Excel Document)

3-10     May 2005 Isolated Fill Sample Descriptions (Microsoft Excel Document)

 

5-10     No Fill Properties List by Address (Microsoft Excel Document)

 

SHEETS

Back Pockets

 

All files below are PDFs. Any PDF greater than 1MB in file size is indicated, and will require a long download time. Please be patient!

Sheet 2             Extent and Thickness of Fill (Blocks C through S) (3MB)

Sheet 3             Extent and Thickness of Fill (Block T)

Sheet 4             Principal Substances of Concern in Fill (7.5MB)

Sheet 5             Principal Substances of Concern in Soil (7.1MB)

Sheet 10           Remedial Alternatives (1.6MB)

 

APPENDICES

Appendix

Stratigraphic Database.......................................................................................................... C

X-Ray Fluorescence Data & Evaluation................................................................................. E (Excel Document)

Fill Area Volume Calculations ............................................................................................... F

Soil/Fill Sample Analyses...................................................................................................... G (Excel Document)

Soil/Fill Sample Analytical Results......................................................................................... H

Laboratory Analytical Results and Data Validation Reports..................................................... I

Town of Hamden Storm Drain Plan........................................................................................ J (no electronic version available)

 

 


 

 

 

 

 

 

 

 

DOCUMENT CERTIFICATION

 

 

I have personally examined and am familiar with the information submitted in this document and all attachments thereto, and I certify, based on reasonable investigation, including my inquiry of those individuals responsible for obtaining the information, that the submitted information is true, accurate and complete to the best of my knowledge and belief.  I understand that any false statement made in the submitted information is punishable as a criminal offense under §53a-157b of the Connecticut General Statutes and any other applicable law.

 

 

 

 

_______________________________________________

Chief Executive Officer (or duly authorized representative)

Olin Corporation

 

 

 

 

 

 


 

 

 

 

 

 

 

 

 

DOCUMENT CERTIFICATION

 

 

I have personally examined and am familiar with the information submitted in this document and all attachments thereto, and I certify, based on reasonable investigation, including my inquiry of those individuals responsible for obtaining the information, that the submitted information is true, accurate and complete to the best of my knowledge and belief.  I understand that any false statement made in the submitted information is punishable as a criminal offense under §53a-157b of the Connecticut General Statutes and any other applicable law.

 

 

 

 

 

 

_______________________________________________

Malcolm Pirnie, Inc.

Responsible for document preparation

 

 

 


1.0           INTRODUCTION

Olin Corporation (Olin) submitted the Supplemental Investigation Report & Remedial Action Plan Non-Public Properties Study Area Hamden, Connecticut (SI) at the request of the Connecticut Department of Environmental Protection (CTDEP) on March 23, 2005 with the realization that an addendum would be prepared to document the two additional rounds of groundwater sampling and characterization at locations that were not accessible due to winter conditions.  Third and fourth quarter rounds of groundwater monitoring were performed in May and August, 2005.  The results from these monitoring events were reported to affected property owners as individual reports and to CTDEP as an addendum in October 2005.  Olin continued its soil investigation during May 23 – 26, 2005 on 48 properties.  Olin had not previously drilled borings on 19 of these properties.  The data from the May 2005 sampling event were submitted to the CTDEP and affected property owners in the form of individual property reports during July 2005.  On November 10, 2005, the CTDEP issued comments to Olin Corporation on the Department’s review of the SI report.  Malcolm Pirnie, Inc., on behalf of Olin, has prepared this Addendum Report to incorporate the results of the May 2005 sampling event into the Conceptual Site Model (CSM) and findings for the Site.

The Supplemental Investigation Work Plan and the SI report should be consulted regarding the initial CSM, including the descriptions of contiguous fill areas, definitions of terms, data quality objectives, and the scope of work.  This addendum report is principally concerned with refining aspects of the CSM regarding the presence and extent of isolated fill.  Therefore, it includes the following revised elements:

·        Graphical presentation of the edge of contiguous and isolated fill areas.

·        Tabular and graphical summaries of documentary, field, and historical data regarding isolated fill.

·        Tabular presentation of field and laboratory analytical data.

·        Tabular and graphical summary of properties where no fill was found.

These elements were evaluated together to update the CSM and conclusions with minor refinements, where necessary, for the Non-Public Properties Study Area. 

As a signatory to the Consent Order, the Town of Hamden granted access to perform work in public rights-of-way within the Study Area.  Before entering a private property within the NPP Study Area to perform an investigation activity, permission was obtained from the property owner via a signed access agreement letter prepared by Olin.  In April 2004, access agreement letters were mailed to the owners of 303 non-public properties.  By the time field investigation activities began on June 7, 2004, access was granted to 133 properties (44%).  Significant efforts and resources were continually used to obtain access to more properties.  Activities included repeat mailings by certified mail with return receipt, numerous attempts to reach owners by phone, and many attempts to speak to owners face to face.  By August 5, access was granted to 219 properties (72%); by September 7, the number was 260 properties (86%).  At the suspension of field investigation activities on February 10, 2005 due to weather conditions, access was obtained from 289 properties (95%).  Two more access agreements were received during resumption of the investigation in May 2005, for a total of 291 properties (96%). 

Cooperation from the residents in the Study Area enabled the investigation to achieve its data quality objectives.  There are no significant data gaps for the 12 properties where access was not obtained.  Wherever feasible, conclusions about these properties were inferred based on the results from neighboring properties and previous investigations.  Sufficient data have been gathered from the Voluntary Initial Investigation and the Supplemental Investigation to support the conclusions stated later in this report.  No additional field investigation work is necessary to achieve the objectives of this investigation. 

The data quality objectives (DQOs) remain the same as detailed in the March 2005 SI Report.  That report described the iterative process used to identify and delineate contiguous and isolated fill areas and to characterize the fill for substances of concern (SOCs).  In this case the data quality objective is spatial.

These DQOs were addressed through research into site history, interviews with knowledgeable individuals (including property owners), historic maps, photographs, correspondence, reports, and field work.  Only the edge of fill must be mapped on a parcel-specific scale so that the degree of contiguous fill at any given parcel can be predicted and remedial decisions can be made for each separately owned parcel of the study area.  The same parcel-specific DQO is needed for finding and characterizing isolated fill areas because of the general absence of detailed historical documentation and their presumed smaller extent.  This information is summarized in the March 2005 SI Report, revised in the following sections, and evaluated to determine if there is enough information of sufficient detail or quality to meet the objectives.   

Aside from one property where access was not granted and subsurface conditions could not be inferred, the CSM is considered complete and representative of conditions.  Data from various sources are in agreement and successfully predict the observed conditions.  The DQOs resolved the data gaps such that the problems can be logically explained to the stakeholders, and a remedial action plan can be developed.  The remainder of this report presents the scope of work used to meet the DQOs and the updated CSM resulting from the supplemental investigation activities. 

 


2.0           SUPPLEMENTAL INVESTIGATION SCOPE OF WORK

This section describes the scope of work conducted during the May 2005 supplemental investigation efforts in accordance with the work plan as modified by the conditional approval letter, the approved Interim Report, and additional requests by CTDEP.  At each step in the iterative process, a proposal for additional work was reviewed by CTDEP.  Comments were discussed in meetings with CTDEP and work scopes were revised accordingly, resulting in a continuous approval process between the investigators and CTDEP.  The descriptions of the field work presented in the March 2005 SI Report are still applicable and are further detailed here in response to CTDEP comments.

Table 2-1 summarizes all investigation activities conducted on each parcel in the NPP study area.  The table below summarizes the investigation activities conducted in the NPP study area during May 2005 and total for the project.

Summary of Investigation Activities

 

May 2005 Field Work

Total Field Work

Properties Inspected

*

290

Properties Sampled

48

267

Contiguous Fill Delineation Borings

14

457

Isolated Fill Delineation Borings

87

413

Bare Spot Samples Analyzed by XRF

4

167

Fill Samples Analyzed by XRF

38

193

Native Soil Samples Analyzed by XRF

63

382

Total Samples Analyzed by XRF

105

742

Total Samples Analyzed by Laboratory

34

598

Total Groundwater Samples Analyzed

31

151

            *  The properties characterized in May 2005 were inspected before Nov. 2004.

 

Boring and sample locations from all investigations conducted in the NPP are shown on Sheets 2 and 3.  The locations of borings and samples collected as part of Olin’s Supplemental Investigation were plotted on site maps in the field by measuring distances in at least two directions to known landmarks, such as buildings and fence-lines.  These locations were accurately transferred into computer (CADD) base maps.  The CADD maps were then transferred to a GIS system, which is linked to analytical and stratigraphic data collected at each boring location.

To obtain a more precise delineation of the approximate edge of contiguous fill investigated in previous sampling events, investigations of select properties along the edge (access permitting) were conducted via iterative, shallow subsurface borings.  A total of 11 non-public properties were revisited and a total of 14 borings were drilled to further delineate the edge of contiguous fill.  These borings were drilled in accordance with the approved Scope of Work outlined in Section 3.2 of the Supplemental Investigation Work Plan dated July 2003, revised January 2004.  A total of 10 fill and 13 native soil samples were collected from the 14 borings associated with contiguous fill delineation.  All samples were analyzed in the field for metals with an x-ray fluorescence (XRF) device.  The results of the XRF field screening are shown in Appendix E.  Based on the XRF results and previous site investigation knowledge, three native soil samples were submitted for laboratory analysis for the substances of concern (SOC) listed below.  The selected samples had the highest XRF lead concentrations or were from an area not previously characterized.  In addition, to augment the characterization of fill in Block T, one fill sample was analyzed by a certified laboratory for the following substances reasonably expected to be found in the contiguous fill:

§         Total and SPLP metals by methods 6010B/7470A and 1312

§         ETPH by method CTETPH

§         PAHs by method 8270C

§         Pest/PCBs by method 8081 (only in areas where filling may have postdated the mid 1930s as described in the Conceptual Site Model)

If ETPH concentrations in samples from around fill pre-dating the mid-1930s were elevated, then these samples were also analyzed for pesticides and PCBs. 

Any additional sample with XRF lead concentration exceeding 200 mg/kg was submitted for laboratory analysis of total lead and arsenic.  Five fill samples met this criterion.

The locations of the May 2005 borings and the revised edge of fill and fill thickness lines are plotted on Sheets 2 and 3. 

The March 2005 SI Report presented the results of the 322 borings drilled at 75 properties and the initial inspections performed on 124 properties outside the known contiguous fill areas.  In May, a total of 87 borings were drilled on 38 properties in the NPP study area to better delineate the extent of each area of isolated fill identified in March 2005 SI Report.  As previously stated, the iterative process used in January and February 2005 was continued during the May 2005 event.  Four borings were typically drilled around and approximately 20 feet away from a boring where isolated fill was identified, with additional borings drilled if necessary in a manner similar to that for transects until the isolated fill area was delineated.  Each isolated fill area was delineated to the extent practicable, limited in a few instances by physical features or lack of permission to access a property.

At locations inaccessible to the direct-push rig, borings were advanced in two-foot lengths by manually augering a one-inch diameter core with an acetate liner.  The isolated fill borings fully penetrated fill materials, if encountered, and advanced into native soil.  All logging, sampling, and screening procedures used for direct-push borings were used with the hand augered borings.  Due to smaller diameter core, sample size was sometimes smaller, particularly in cores with low recovery. 

As part of the investigation outside the known contiguous fill areas, additional borings were drilled in five surface depressions and in two areas where “debris” was reported.  Isolated fill was found in three of the surface depressions, but not at the “debris” areas.  These areas were subsequently delineated according to the iterative process previously described. 

The materials encountered were evaluated for color, odor, and texture and field screened for concentrations of volatile organics using a photoionization device.  One sample was collected from a 2-foot interval in each boring and field screened using XRF.  The results of the XRF field screening are presented in Appendix E.  Samples were selected for laboratory analysis that had the highest XRF lead concentrations or were from an area not previously characterized.  Based on the XRF results and previous site investigation knowledge, seven isolated fill samples were submitted for laboratory analysis for total and SPLP metals, ETPH, and SVOCs.  Any additional soil sample with XRF lead concentration exceeding 200 mg/kg was submitted for laboratory analysis of total lead and arsenic.  Eleven isolated fill samples met this criterion.

The locations of the May 2005 borings and the revised edge of isolated fill lines are plotted on Sheets 2 and 3.  

2.2.1              Bare spot sampling

As discussed in section 2.2.2 of the March 2005 SI Report, CTDEP requested that bare spots overlying isolated fill areas be sampled and analyzed in the field by XRF.  Four of these bare spots could not be sampled during January and February 2005 due to snow cover.  During May 2005, these bare spot samples were field screened by XRF and two samples were submitted to the approved laboratory for PAH, as well as total and SPLP lead and arsenic analyses. 

A total of 31 wells (29 new wells and 2 existing wells) were sampled during the four quarterly rounds of groundwater sampling completed by August 2005 as part of the NPP groundwater investigation.  All of the wells were sampled in accordance with the QAPP with the exception of E2001D.  This well is screened in bedrock and exhibited a very slow recharge rate and substantial draw-down during low-flow purging.  Sample turbidity did not stabilize or fall below 5 NTUs.  Consequently, the metals samples from E2001D were filtered using a 0.45-micron filter during both the November 2004 and February 2005 rounds.  Two existing wells (MS-109-MW and WIN-1067-MW) also could not be sampled in accordance with the QAPP because they contained insufficient water for sampling.  After several attempts to purge these wells at a low-flow rate (100 ml/min), the wells ran dry and did not recharge sufficiently to collect samples.  These wells are very shallow and do not have adequate screen length below the water table.  During the four rounds of groundwater monitoring, well MS-109-MW could not be sampled at all, while well WIN-1067-MW was able to be sampled only once, during the May 2005 event. 

Well development purge water, well sampling purge water, and wash water used to clean and decontaminate well drilling equipment was containerized in 55-gallon drums for proper off-site treatment/disposal.  One batch of purge and decontamination water was disposed of at United Industrial Services Inc. in Meriden, Connecticut.  The last batch of purge and decontamination water from the Supplemental Investigation was disposed of at Clean Harbors Environmental Services in Bristol Connecticut.

The purpose of the data validation review is to determine the usability of the data generated by the laboratory by evaluating specific quality assurance and quality control (QA/QC) parameters.  All laboratory analytical data generated for Olin during the Supplemental Investigation (June 2004 – August 2005) were reviewed by an independent, third-party and evaluated in accordance with the approved project QAPP, and with guidance from the USEPA CLP National Functional Guidelines for Organic and Inorganic Data Review.  This review is consistent with the July 2005 CTDEP draft guidance on Reasonable Confidence Protocols (RCPs) for enhanced laboratory QA/QC procedures for analytical methods and reporting.  The data validation report for the data collected by Olin from May 2005 is included on CD in Appendix I.  This report does not comment on the validity of data collected by other investigators.  The specific QA/QC parameters are:

 

  • Chain-of-Custody Documentation
  • Laboratory Narrative Discussion
  • Holding Times
  • Field, Trip, and Method Blank Contamination
  • Surrogate Compound Recoveries
  • Sample Matrix Spike/Duplicate Recoveries and Correlations

·        Laboratory Control Sample (LCS) Spike Recoveries

  • Field Duplicate Correlations
  • ICP Interference Check Samples

The evaluation indicates the accuracy and precision of the sample results reported by the laboratory.  If standard QA/QC parameters were found to lie outside validation action limits, results for those analytes may be qualified (list of qualifiers may be found in Appendix I) or rejected.  For example, in the few instances when holding times were exceeded, appropriate corrective actions were taken by the laboratory and affected data were flagged accordingly (“J” or “R” flag).

According to the data validator, “In summary, the organic and inorganic analyses were performed acceptably and the data quality is good.  There does not appear to be a significant sample matrix effect on [SOC] recoveries, and most results are usable as reported, or usable with minor qualification of reported results as estimated in value.  Some low level analyte detections are considered external contamination.”  Results for the principal SOCs (arsenic, lead, SPLP lead, PAHs, and ETPH) were not significantly qualified with one exception.  Benzo(b)fluoranthene and benzo(k)fluoranthene were reported as a combined value as benzo(b)fluoranthene in several samples, due to the matrix effect on resolving the analytes.  This creates a falsely high result for the former and falsely low result for the latter.  Therefore, the results for those two compounds in the affected samples are considered as estimated (“J”), with those stated biases.  The CTDEP RSR criteria are more strict for benzo(b)fluoranthene, so the reported bias occurs in a more conservative direction.  The combined values reported as benzo(b)fluoranthene in some of the affected samples exceed the RSR criteria, whereas they may not have been if the compounds had resolved.

The data validation reports confirm that the QA/QC procedures for the Supplemental Investigation followed during field sampling and in the laboratory produced reliable results according to the data quality objectives established in the work plan.  None of the qualified data affect the findings presented in this report.  Data generated by other investigators are presented in this report for information only.  No assumption is made as to the validity or quality of those data.  However, given the magnitude of data collected as a result of the Initial and Supplemental Investigations, there are no significant data gaps that affect the overall conclusions and recommendations of this report.

 


3.0           CONCEPTUAL SITE MODEL

Development of a CSM is an iterative process.  Available data are evaluated to develop an initial hypothesis and identify data gaps.  As new data are collected and data gaps filled, the CSM is refined and revised as necessary.  The goal of each round of investigation activities was to address data gaps remaining after the previous round, and to modify the CSM based on the results.  The data gaps addressed in the May 2005 investigation were associated with delineating and/or confirming a few areas of isolated fill and minor portions of the edge of contiguous fill.  The basic CSM presented in the Supplemental Investigation Report (March 2005) remains intact and is only slightly modified following the May 2005 event.  These modifications are presented below.  Stratigraphic data and the location of the source information for the 101 new borings are summarized in a supplement to Appendix C.  A summary of the 34 soil/fill sample analyses and the analytical results are provided in supplements to Appendices G and H, respectively.

During the quality review portion of the iterative process used to delineate the areas of contiguous fill within the NPP study area, eleven properties were identified as requiring further investigation.  During the May 2005 event, a total of 14 borings were drilled to further refine the delineation of contiguous fill.  Based on the results of these borings, the contiguous fill delineation was revised.  These revisions are discussed below by block, contiguous fill area, and property address.  The revised contiguous fill delineations are depicted on revised Sheets 2, 3, 4, 5, and 10.  Revised analytical data summaries are presented in Tables 3-2, 3-3, and 3-5.

3.2.1              Block E – Newhall Street Area

3.2.1.1              1048 Winchester Avenue

One boring was drilled along the western boundary of the property to confirm that the contiguous fill previously delineated did not extend south of the retaining wall along the Newbury Street side of this property.  The previously delineated contiguous fill line was confirmed and no changes were made.  The only area where fill was found here was in the lower half of the driveway where up to 1.3 feet of disturbed soil fill was found.

3.2.1.2              22 Newbury Street

Two borings were drilled along the western boundary of the property to verify the contiguous fill line along the western portion of the property.  Disturbed soil fill was identified within the western portion of the property to a depth of up to 2.4 feet and the contiguous fill line was revised accordingly, as shown on Sheet 2.

3.2.2              Block J – Southwest Satellite Area

3.2.2.1                293 and 297 Goodrich Street

Borings were drilled along the northern boundary of each of these properties to complete transects from the adjacent property (17 Edwards Street).  No fill material was found on either property, confirming the fill line previously delineated, as shown on Sheet 2.

3.2.2.2              300 and 304 Morse Street

Borings were drilled along the southern boundary of each property to complete transects from adjacent properties and to investigate the presence of fill within the southern portion of these properties.  No fill material was found on either property and the contiguous fill delineation was revised accordingly, as shown on Sheet 2. 

3.2.3              Block L – Southwest Satellite Area

3.2.3.1               453 Shelton Avenue

An additional transect was drilled along the northern boundary to further delineate the contiguous fill to the north.  One boring in the northeastern corner of the property found fill material to a depth of 1.1 feet confirming the fill line previously delineated, as shown on Sheet 2.

3.2.4              Block Q – Newhall Street Area

3.2.4.1              16 Marlboro Street

One boring was drilled along the western boundary of the property to complete a transect from the adjacent property and to refine delineation of contiguous fill to the west.  No fill material was found on the property, and the contiguous fill line was revised accordingly, as shown on Sheet 2.

3.2.5              Block T – Augur Street Area

3.2.5.1              331 Augur Street

Two borings were drilled within the northern portion of the property to delineate contiguous fill in the northern portion of the property.  Disturbed soil fill was found to a depth of 3.1 feet, resulting in a revision to the 4-foot fill contour, as shown on Sheet 3. 

3.2.5.2              13 and 17 Harris Street

Two borings were drilled within the western portion of each property to better delineate the 4 and 10-foot contour lines in the western portion of the contiguous fill area.  The results show fill was found to a maximum depth of 6 feet in the western portion of 17 Harris Street.  The resulting fill contour lines shown on Sheet 3 are adequately delineated. 

One of the objectives of the Supplemental Investigation was to investigate portions of the NPP study area outside areas of contiguous fill where smaller, isolated areas of filling may be present.  The March 2005 SI Report identified 33 isolated fill areas, encompassing a total of approximately 3 acres in 10 blocks within the NPP Study Area.  The total estimated volume of isolated fill was approximately 8,500 yd3 with an average depth of 1.8 feet.

Due to access issues and the inability to advance hand auger borings through frozen ground, not all isolated fill areas were adequately delineated when the Supplemental Investigation Report was submitted in March 2005.  However, delineation of these areas was successfully completed during the May 2005 sampling event using the iterative process and scope of work described in Section 2.2.  Revised delineation boundaries are shown on Sheets 2 and 3.  The rationale for investigation of each property located outside the contiguous fill areas is summarized in Table 3-9.  Descriptions of each isolated fill boring drilled in May 2005 are presented in Table 3-10.  The vast majority of isolated fill observed in the borings consists of disturbed soil fill less than two feet thick, underlain by native sands.  Specifically, the composition is typically reworked sand with minor or trace amounts of rock, ash, slag, glass, coal, ceramic, concrete, and/or brick; or processed sand and gravel (traprock), especially in the rights-of-way.  Most of the “debris” reported by owners/tenants also consists of these materials.  In a few instances the fill was deeper than 2 feet and/or consisted of refuse or waste fill.  Fill found in rights-of-way and under roads may be associated with road building/grading and utility installation rather than an extension of fill from the adjacent properties. 

Based on the revised delineation resulting from the May 2005 field work, the total area of isolated fill areas is still approximately 3 acres.  Minimum total volume is approximately 9,000 yd3 (a 6% increase from the March 2005 SI Report) with an average fill depth of 2.5 feet (based on borings penetrating fill).  Appendix F presents calculations of the volume for each isolated fill area.  Isolated fill areas were not found in blocks A, C, F, J, and L.

Laboratory analyses and the resulting analytical data for the soil and fill samples collected in May 2005 are tabulated in Appendices G and H.  The raw laboratory data reports are included in Appendix I.  Analytical data summaries for each SOC analyzed, detected, and/or exceeding RSR criteria are presented in Table 3-6 for the isolated fill areas.  The samples are categorized into those in fill, soil underlying fill, and soil adjacent to fill, which is defined as within 25 feet of the edge of fill.  Samples more than 25 feet from a mapped fill area are categorized as ambient samples, which are summarized in Table 3-7.  The adjacent and ambient soil samples are mostly surficial (0 to 0.5 feet deep) or shallow (0 to 2 feet deep) sand and typically incorporate surficial topsoil.  (Table 3-7 includes 3 samples apparently of disturbed soil fill collected by CTDEP from rights-of-way borings 168-MOR, 303-MS, and 304-MS.)  These samples characterize the presence of SOCs that may have migrated to or accumulated within the topsoil from any number of potential sources besides filling.

Sheets 4 and 5 present seven maps of the Study Area displaying the locations and concentration ranges in fill and soil, respectively of the principal SOCs arsenic, lead, SPLP (including TCLP) lead, benzo(a)pyrene (representative of PAHs), and ETPH (including TPH), as well as overall compliance with the RDEC and GAPMC for any substance.  Inspection of the complete data set shows that the principal SOCs are the most common substances exceeding RSR criteria and essentially define the scope of the non-compliance.   Overall, the most widespread non-compliant SOCs are lead and SPLP lead, with 54 of 113 and 42 of 59 isolated fill sample analyses exceeding RDEC and GAPMC, respectively (Table 3-6).  Adjacent soil samples are mostly affected by SPLP lead (10 of 47 analyses exceed GAPMC), with a few total lead and arsenic, SPLP antimony and arsenic, and PAHs also exceeding RSR criteria.  These same SOCs are commonly detected in ambient soil samples as well. 

Updated descriptions of individual isolated fill areas investigated in May 2005 are presented below. 

Block E

Two isolated fill deposits in Block E designated E01 and E02 were delineated further and are discussed separately below.

E01

Isolated fill area E01 is located in the central portion of block E.  It is located behind the garage at the rear of 165-167 Morse Street and at the rear of adjacent properties located at 18 Newbury Street, 22 Newbury Street, and potentially to the adjacent rear of 171-173 Morse Street.  This fill area covers approximately 4,700 ft2 and contains an estimated 260 yd3 of fill, based on an average thickness of 1.5 feet.  The maximum fill thickness was at boring E1063 where 2.4 feet of disturbed soil fill was found.  Boring E1056 was the only boring in this fill area to penetrate waste fill.  The other seven borings located in E01 penetrated disturbed soil fill that was composed of sand mixed with traces of white ash, black ash, and coal. 

Three samples were analyzed for SOCs and all three exceed the RDEC for lead of 400 mg/kg (E1055S1 at 447 mg/kg, E1034S1 at 3,040 mg/kg, and E1062S1 at 524 mg/kg).  Sample E1034S1 also exceeds GAPMC for SPLP lead and antimony.  Two adjacent soil samples (E1005S1 22.6 ug/l and E1057S1 18.3 ug/l) also exceed the GAPMC for SPLP lead.  No other RSR criteria were exceeded in samples from within or adjacent to E01. 

E02

Isolated fill area E02 is located in the central portion of block E just southeast of isolated fill area E01 and underlies the rear of the property at 1030 Winchester Avenue.  E02 is delineated in all four cardinal directions by borings within 20 feet.  This fill area covers approximately 1,100 ft2 and contains an estimated 56 yd3 of fill, based on an average thickness of 1.4 feet.  Boring E1035 penetrated a maximum fill thickness of 2.1 feet.  The three borings penetrated disturbed soil fill composed mostly of sand with traces of ash, brick, and coal. 

Two samples were analyzed for SOCs.  One sample exceeds the RDEC for lead (E1050S1 475 mg/kg) and both exceed the GAPMC for SPLP lead.  Sample E1035S1 also exceeds the GAPMC for SPLP cadmium.  One adjacent soil sample (E1057S1), which lies between this fill area and area E01, also exceeds the GAPMC for SPLP lead.  No other RSR criteria were exceeded in samples from within or adjacent to E02.

Block H

One isolated fill deposit in Block H designated H01 was further delineated and is discussed below.

H01

Isolated fill area H01 is located in the southern portion of block H.  It underlies the southeastern corner of 17-19 St. Mary St. and the northwest corner of 319 Goodrich Street.  This fill area potentially extends behind the garage along the northern edge of 321 Goodrich Street.  Only the area west of the garage was accessible for drilling, where no fill was found.  It is delineated in all directions by five borings within 20 feet and one within about 40 feet.  This fill area covers approximately 1,480 ft2 and contains an estimated 60 yd3 of fill, based on an average thickness of 1.1 feet.  The maximum depth of fill is 1.8 feet at boring H1069.   The four borings located in H01 penetrated disturbed soil fill that is composed of dark brown topsoil with traces of coal.  A small surface depression and bare spot area are located in this fill area. A larger surface depression is located outside of the fill area to the north, where no fill was found.

Five samples from this fill area were analyzed for SOCs.  Two samples exceed RSR criteria: H1072S1 for SPLP lead; and surface sample H3008S1 for total lead and several PAHs.

Two adjacent soil samples just to the west and south also exceed RSR criteria:  H1073S1 for total and SPLP arsenic, SPLP lead, and several PAHs; and H3008S1 for total lead and several PAHs.

Block K

Three isolated fill deposits in Block K designated K01, K05, and K06 were delineated and are discussed separately below.  Minor adjustments to the descriptions of areas K02 and K04 are also included.

K01

Isolated fill area K01 is located in the northern portion of K block.  K01 consists of the area between the eastern portion of 266 Morse Street, the western portions of 478 to 484-486 Morse Street and the northern parts of the properties at 69 and 73 Marlboro Street.  An “island” of no fill area was delineated from 216 Morse Street to the rear of 478 Newhall Street.  This fill area is bounded by the study area line (which coincides with Morse Street) to the north and borings within 20 feet to the east, west and south.  Due to lack of access at 79 Marlboro Street, the fill area was not delineated at that property.  K01 is approximately 29,700 ft2 and contains an estimated 1,740 yd3 of fill, based on an average thickness of 1.6 feet.  The thickest amount of fill penetrated was at boring K1075, which has 6.3 feet of primarily waste fill with some disturbed soil fill.  Fill in K01 is predominantly composed of disturbed soil fill and localized deposits of waste fill consisting of ash, slag, coal, glass, sand, and gravel. Only thin amounts of disturbed soil fill occur near the eastern edge that appears to coincide with the topography surrounding the large depression to the southeast. 

Twenty samples from this fill area were analyzed for SOCs.  Two samples exceed the RDEC for arsenic and 12 samples exceed the RDEC for lead.  Six samples exceed GAPMC for SPLP lead, one sample exceeds the GAPMC for SPLP arsenic, and one sample (K1023S1) exceeds the RDEC and GAPMC for several PAHs.

Eight soil samples from adjacent to the fill area were analyzed for SOCs.  Two adjacent soil samples (214MORSE-S3 and 214MORSE-S3B) exceed the RDEC for lead (up to 1,800 mg/kg), and three other adjacent samples (K1064S1, K1038S1, and K1128) exceed the GAPMC for SPLP lead.

K02

Isolated fill area K02 is located southwest of isolated fill area K01. It underlies a portion of the southern parking lot at 266 Morse Street, and significant portions of properties at 83, 87 and 91 Marlboro Street.  Borings to the north, west, and south are within 20 feet of the edge of fill line.  The eastern edge is undetermined because the owner of 79 Marlboro Street has not granted access, but the distribution of fill so far mapped suggests that it extends onto this property.  This fill area covers approximately 13,150 ft2 and contains an estimated 780 yd3 of fill, based on an average thickness of 1.6 feet.  This fill area has a maximum depth of 7 feet at boring K1070 (87 Marlboro Street), which is composed entirely of waste fill, however, most borings penetrated disturbed soil fill.  Localized deposits of waste fill are present in the southwest and center of this area.

Twelve samples from this fill area were analyzed for SOCs.  Four samples exceed the RDEC for arsenic, 5 samples exceed the RDEC for lead (up to 1,830 mg/kg), and 3 samples exceed the GAPMC for SPLP lead.  In addition, RSR criteria were exceeded for ETPH, copper, and dieldrin.

Adjacent and underlying soil samples are compliant with RSR criteria.

K04

Isolated fill area K04 is located southeast of isolated fill area K01 and west of Newhall Street.  It has been sufficiently delineated and underlies portions of 466 and 468 Newhall Street as well as 61 and 69 Marlboro.  This fill area covers approximately 5,400 ft2 and contains an estimated 320 yd3 of fill, based on an average thickness of 1.6 feet.  This fill area has a maximum depth of 5 feet at boring K1078 where a former sinkhole was covered with clean fill in May 2004 by Loureiro Engineering Associates, Inc.  Rusted scrap metal, wood and glass bottles were observed in the fill when the sinkhole was collapsed and covered.  Most of the other borings in this fill area penetrated disturbed soil fill composed of sand mixed with trace amounts of black and gray ash, coal, slag, and brick.  Boring K1111 penetrated an 8-inch thick layer of waste fill consisting of coal and brick.

Eight samples from this fill area were analyzed for SOCs.  All samples exceed the RDEC for lead (up to 2,200 mg/kg), and 3 samples exceed the GAPMC for SPLP lead (up to 219 ug/l).  One sample (466NH-HA5-S1) exceeds the arsenic RDEC.

The lead concentration of 5,600 mg/kg in adjacent soil sample 466NH-HA8-S1 exceeds the RDEC for lead.  Other adjacent samples are compliant with RSR criteria.

K05

Area K05 is located along the right-of-way at the corner of Morse Street and Shelton Avenue.  This fill area was found to be limited to the right-of-way and was not found to extend onto the adjacent properties at 274 and 284-286 Morse Street.  This fill area covers approximately 4,440 ft2 and contains an estimated 150 yd3 of fill, based on an average thickness of 0.9 feet.  This fill area has a maximum depth of 1.2 feet at boring K1124, which penetrated 0.8 feet of disturbed soil fill overlying 0.4 feet of waste fill.  Three of the five borings drilled in this area encountered a similar mixture of disturbed soil fill overlying a thin layer of waste fill consisting of black ash.  The fill in this area appears to be associated with historic roadway construction and is not contiguous with other fill areas. 

Two samples from this fill area were analyzed for SOCs.  One sample (K1122S1) exceeds the GAPMC for SPLP lead with a concentration of 42.8 mg/L.  One sample (274 – MOR-S1) exceeds the RDEC and GAPMC for benzo(b)fluoranthene with a concentration of 2,770 ug/kg.

One adjacent sample was analyzed for SOCs and was compliant with RSR criteria.

K06

This area has been delineated and underlies the central to northern portions of two properties at 109 and 115 Marlboro Street.  A CTDEP investigation in December 2001 at 115 Marlboro St. found a trace amount of ash between the garage and swimming pool.  Since then, seven borings were drilled on the two properties.  No fill was observed in borings to the east, south, and west within 20 feet of the fill area.  This fill area covers approximately 1,760ft2 and contains an estimated 80 yd3 of fill, based on an average thickness of 1.3 feet.  The maximum fill depth of 1.4 feet was penetrated at boring location K1135 consisting of disturbed soil fill.  Boring K1130 penetrated waste fill consisting of white and black ash and coal to a depth of 1.1 feet.

Two samples from this fill area were analyzed for SOCs.  One sample exceeded the GAPMC for SPLP lead, and one sample exceeded RSR criteria for total lead and several PAHs.

One sample from adjacent boring K1129 was analyzed for SOCs.  This adjacent sample exceeded the GAPMC for SPLP lead.  All other detected SOCs were compliant with RSR criteria. 

Block M

Two isolated fill deposits in Block M designated M03 and M04 were investigated further and are discussed separately below.

M02

Area M02 is located within the backyard of 80 Marlboro Street.  The property owner refused to grant access to this property during the May 2005 event, so the presence of fill has not been entirely delineated.  Disturbed soil fill composed of sand with traces of ash, coal and glass was found to a depth of 1.6 feet.  The area underlies an estimated 150 ft2 and contains an estimated 10 yd3 of fill.

One sample from this area (M1030S1) was analyzed for SOCs and exceeded both RDEC and GAPMC for chlordane.

M03

Isolated fill area M03 is located within the backyard of 88 Marlboro Street.  This fill area is delineated to the north by the house with one boring finding no fill material within the front yard, to the east by a boring within 20 feet, to the west by a boring finding no fill material along the western property boundary, and to the south by a boring along the southern property boundary.  It covers approximately 300 ft2 and contains an estimated 50 yd3 of fill, based on a thickness of 4.7 feet.  The one boring within the fill area penetrated disturbed soil fill composed of sand with trace amounts of coal. 

The one sample from this fill area (M1042S1) was analyzed for SOCs.  Concentrations detected in this sample exceeded the RDEC for arsenic, the RDEC for lead, the GAPMC for SPLP arsenic and SPLP lead.  This sample also exceeded both the RDEC and GAPMC for several PAHs. 

Adjacent soil sample M1044S1, just to the west, was analyzed for SOCs and is compliant with applicable RSR criteria.

M04

Isolated fill area M04 underlies the backyards of 241 and 245 Goodrich.  This fill area is delineated by borings to the north, south, and east.  This fill area is separated from the Southwest Satellite Fill Area by two borings to the north and northwest.  In addition, fill material and thicknesses found within area M04 were not consistent with borings within the contiguous fill area.  This fill area covers approximately 1,780 ft2 and contains an estimated 110 yd3 of fill, based on an average thickness of 1.7 feet.  It has a maximum depth of 4.5 feet at boring M1049.  All borings within this area penetrated disturbed soil fill composed of sand with traces of ash and coal.

Four samples from within this fill area were analyzed for SOCs.  All four samples contained concentrations of lead exceeding the RDEC.  Sample M1048S1 also exceeded the GAPMC for SPLP lead, as well as the RDEC and GAPMC for several PAHs.

One soil sample (M1003S1) taken from an adjacent boring north of this area contained a concentration of SPLP lead exceeding the GAPMC.  All other adjacent soil samples were compliant with RSR criteria.

Block N

Two isolated fill deposits designated N03 and N04 were further delineated in May 2005 and are discussed separately below.

 

N03

Isolated fill area N03 underlies the backyards (northern portions) of properties at 199, 203, 207-209, and 211-213 Goodrich Street.  The extent of this fill is unknown to the north, because access was not granted to 163 Shepard Street.  Borings to the south, east, and west are within 20 feet of the observed fill.  This fill area covers approximately 3,050 ft2 and contains an estimated 130 yd3 of fill, based on an average thickness of 1.2 feet.  It has a maximum depth of 1.9 feet at boring N1024.  Most borings penetrated disturbed soil fill.  One boring, N1024, penetrated a layer of waste fill composed of sand with some coal, glass, and slag.

Eight samples from this fill area were analyzed for SOCs.  Three samples from within this area contained concentrations of lead exceeding the RDEC ranging from 411 to 685 mg/kg.  The SPLP lead concentration in sample N1018S1 exceeds the GAPMC. 

One adjacent soil sample (N1036S1) exceeded the RDEC and GAPMC for arsenic and lead.  Two adjacent soil samples located to the south and east are compliant with RSR criteria. 

N04

Area N04 located in the southwestern corner of 199 Goodrich has been delineated by borings finding no fill material to the north, east, and west.  The area is bordered to the south by the limits of the NPP study area.  One CTDEP surficial hand auger sample, HA-2, which found disturbed soil fill described as “red-brown sand, slag & glass”, defined this area prior to May 2005.  Two additional borings drilled in May 2005 found similar fill material to a maximum depth of 1.9 feet at boring N1028.  This area covers approximately 620 ft2 and contains an estimated 30 yd3 of fill based on an average thickness of 1.4 ft. 

One sample from this area (N1029S1) was analyzed for SOCs and exceeded the GAPMC for SPLP lead.

Block P

One isolated fill deposit found in Block P, designated P02, was further delineated during May 2005 and is discussed below.

P02

Isolated fill area P02 is located approximately 20 feet northeast of P01 underlying portions of the backyards of 164 Morse St. and 1002 Winchester Avenue.  The area is now bound by borings in all four cardinal directions, underlies approximately 1,050 ft2, and contains an estimated 52 yd3 of fill, based on an average thickness of 1.4 feet.  It has a maximum depth of 1.7 feet at boring P1039.  The two borings in this fill area penetrated disturbed soil fill composed of sand with trace amounts of coal, glass, and slag.

Two samples from within the fill area were analyzed for SOCs.  Sample P1039S1 exceeded the RDEC for arsenic and the GAPMC for SPLP arsenic and lead. 

Two adjacent soil samples collected from north of the fill area are compliant with RSR criteria. 

Block Q

Three isolated fill deposits were revisited and delineated during May 2005 in Block Q designated Q01 to Q03.  They are discussed separately below.

Q01

Isolated fill area Q01 is located at 976 Winchester Avenue in the northeastern portion of block Q.  This area underlies the southeast corner of the property and is delineated on all sides by borings within 20 feet of the isolated fill line.  This fill area underlies an area of approximately 110 ft2 and contains an estimated 6 yd3 of fill, based the 1.5-foot thickness of disturbed soil fill in boring Q1018, consisting of sand with a piece of glass, trace slag, and gravel. 

One sample was collected from within this fill area and analyzed for SOCs.  Sample Q1018S1 exceeds the GAPMC for SPLP lead.

One adjacent soil sample, Q1042S1, was analyzed for SOCs and is compliant with RSR criteria.

Q02

Area Q02, in the rear of the property at 976 Winchester Avenue, has been delineated on all sides by borings within 20 feet of the fill line.  This area underlies approximately 180 ft2 and contains an estimated 8 yd3 of fill.  Disturbed soil fill was found in this area consisting of sand with white ash and coal to a maximum depth of 1.4 feet.

Two samples from within this fill area were analyzed for SOCs.  One sample, Q1047S1, exceeds the RDEC for lead.  Sample Q1031S1 exceeds the RDEC for arsenic and lead.

One sample collected from adjacent to the fill area was analyzed for SOCs.  This sample, Q1048S1, exceeds the GAPMC for SPLP lead.

Q03

Area Q03 is located in the backyard at 155 Goodrich Street and has been delineated in all directions by borings within 20 feet of the fill line.  Disturbed soil fill consisting of sand with some coal to a depth of 0.8 feet was found in boring Q1034 where debris was reported behind the garage.  The delineated area covers approximately 360 ft2 and contains an estimated 11 yd3 of fill. 

One sample from within this fill area was analyzed for SOCs and exceeded the GAPMC for SPLP lead and chlordane. 

One adjacent sample was collected from outside the fill area.  This sample, Q1052S1, was compliant with RSR criteria.

Block R

One isolated fill deposit found in Block R was further delineated during May 2005.  It is designated R01 and is discussed below.

R01

Isolated fill area R01 is located in the southern portion of block R.  It underlies the rear of properties at 10 North Sheffield St. and 959-957 Winchester Avenue.  This isolated fill area has been delineated on all sides by borings within 20 feet.  The delineated fill area covers approximately 1,540 ft2 and contains an estimated 85 yd3 of fill, based on an average thickness of 1.5 feet.  The maximum depth of fill of 1.8 feet is at boring R1043, which is located in the north of this isolated fill area.  One of the five borings penetrated a thin (0.4’) layer of waste fill and the other four penetrated disturbed soil fill that consists of sand with trace coal, glass, white ash, and slag.

Two samples from within this fill area were analyzed for SOCs.  One sample (R1041S1) exceeds the GAPMC for SPLP lead, while the second (R1036S1) exceeds the RDEC for arsenic and the GAPMC for both SPLP arsenic and SPLP lead.

Two adjacent soil samples were analyzed for SOCs and are compliant with RSR criteria.

Block S

Three isolated fill deposits found in Block S, designated S04 to S06, were further delineated during May 2005 and are discussed separately below.

S04

Isolated fill area S04 is located in the southeast corner of 14 Prospect Lane.  This fill area is delineated to the west, north, and south by borings within 20 feet.  There are no borings to the east because this fill area intersects the road and NPP Study Area boundary.  This fill area underlies approximately 1,290 ft2 and contains an estimated 64 yd3 of fill, based on an average thickness of 1.4 feet.  It has a maximum depth of 1.8 feet at boring S1073 and is characterized by disturbed soil fill containing sand with some brick, coal, and ash.

One sample from within this fill area was analyzed for SOCs.  This sample (S1070S1) exceeded the GAPMC for SPLP lead and RDEC and GAPMC for several PAHs.

One adjacent soil sample (S1071S1) was analyzed for SOCs and is compliant with criteria.

S05

Isolated fill area S05 is located in a shallow topographic depression within the center of block S.  Sections of the fill boundary closely match the existing topographic contour lines.  S05 includes portions of back yards extending from 29 N. Sheffield St. in the south, to 41 N. Sheffield St. in the north, and includes backyard portions of 34 and 40 Prospect Lane to the east.  It is delineated on all sides by borings within 20 feet.  It underlies approximately 10,840 ft2 and contains an estimated 1,070 yards3 of fill, based on an average thickness of 2.7 feet.  This fill area contains two deposits that are greater than 4 feet thick and reaches a maximum depth of 6.0 feet at boring S1020.  It is characterized by disturbed soil fill containing sand with some brick, coal, white ash, black ash, and glass.  Boring S1044 penetrated a thin layer of waste fill.

Eight samples from within the fill area were analyzed for SOCs.  Two of these samples exceed the RDEC for lead, while two of them exceed the GAPMC for SPLP lead. 

Surrounding samples are compliant with criteria except for sample S1032S1, which exceeds the GAPMC for SPLP lead.

S06

Isolated fill area S06 is located at 40 Prospect Lane.  This fill area is delineated to the west, east, and north by borings within 20 feet.  There are no borings to the south because this fill area intersects the road and NPP study area boundary.  This fill area covers approximately 5,250 ft2 and contains an estimated 410 yd3 of fill, based on an average thickness of 2.1 feet.  It has a maximum depth of 5.7 feet at boring S1062.  This isolated fill area is characterized by disturbed soil fill containing sand with trace ash and coal.  Boring S1016 penetrated a thin layer of waste fill in addition to the disturbed soil fill.

One sample collected from within this fill area (S1016S1) was analyzed for SOCs and exceeded the RDEC for ETPH, arsenic, lead, and several PAHs.  This sample also exceeded the GAPMC for SPLP lead and several PAHs. 

One adjacent sample (S1015S1) was analyzed for SOCs and also exceeded the RDEC and GAPMC for several PAHs.

Block T

Two isolated fill deposits found in Block T, designated T01 and T04, were further delineated during May 2005 and are discussed separately below.

T01

Isolated fill area T01 is located in the northeastern portion of block T.  It underlies portions of properties from 670, 672, and 678 Newhall St. and 323, 327, and 329 Augur St.  This fill area is delineated to the east, south and west by borings within 20 feet.  There are no borings to the north because this fill area intersects the NPP Study Area boundary.  This fill area underlies approximately 18,900 ft2 and contains an estimated 1,170 yd3 of fill, based on an average thickness of 1.7 feet.  This fill area has a maximum depth of 4.0 feet at boring T1079.  It is characterized by disturbed soil fill containing sand with trace white ash, coal, and wood.

Four samples collected from within this fill area were analyzed for SOCs.  Three of the four samples were not compliant with RSR criteria.  Two samples (T1077S1, T1079S1) exceed the RDEC for lead; one sample (T1079S1) exceeds the RDEC for lead and arsenic, as well as the GAPMC for SPLP lead; and the fourth sample (T1004S1) exceeds the GAPMC for two pesticides (chlordane and heptachlor epoxide).

Two adjacent soil samples were analyzed for SOCs and are compliant with RSR criteria.

T04

Isolated fill area T04 is located in the northern portion of the property at 634 Newhall Street.  This fill area is delineated in all cardinal directions by borings within 20 feet.  It underlies approximately 680 ft2 and contains an estimated 43 yards3 of fill, based on an average thickness of 1.7 feet.  Disturbed soil fill consisting of sand and glass was penetrated to a depth of 1.7 feet within this fill area.

One sample (T1027S1) was collected from within this small fill area and analyzed for SOCs.  This sample is compliant with RSR criteria.

In an attempt to delineate the boundaries of landfilling in the Newhall Street neighborhood, CTDEP drilled 65 borings in rights-of-way in January and February 2001.  Fourteen borings were identified in the investigation report (June 14, 2001) as containing fill.  Not included in the list were borings 168-MOR, 303-MS, and 304-MS, and 28-PL.  However, not having seen the material, Malcolm Pirnie conservatively interpreted the logs of these borings as containing disturbed soil fill.  Malcolm Pirnie drilled borings adjacent to these borings to confirm if fill is present and delineate the extent of fill, if necessary.

The CTDEP log for 168-MOR described the boring as: 

0 to 1 feet - “black organic”

2 to 8 feet – “reddish brown coarse sand”

Malcolm Pirnie classified the “black organic” as disturbed soil fill and to confirm or delineate this potential isolated fill area drilled three borings in the vicinity of 168-MOR.  In boring P1013, 1.1 feet of silty brown sand (disturbed soil fill) was underlain by 0.4 feet of waste fill underlain by native red-brown medium sand with little silt and some gravel.  No fill was found in boring P1037, located in the right-of-way, and boring P1044 located in the front yard of 168 Morse Street close to the sidewalk.  Both borings were described as containing red-brown medium sand with some fine gravel.  Therefore, the presence of fill was not confirmed in this area.

The CTDEP log for 303-MS was described as: 

0 to 6 inches – dark brown loam, grass

6 inches to 1 foot – dark brown loam

1 to 2 feet – trap rock, basalt (4”)

2 to 8 feet – light brown medium sand. 

Malcolm Pirnie classified the upper two feet as disturbed soil fill and to confirm or delineate this potential isolated fill area drilled boring A1059 in the right-of-way in the vicinity of 303-MS and encountered the following stratigraphy:

            0 to 0.5 feet – top soil

0.5 to 1.1 feet – gravel and road sub-base

1.1 to 2.1 feet – red brown fine-medium sand, trace fine-medium gravel

2.1 to 3 feet - red brown medium coarse sand, little fine-medium gravel

 

The CTDEP log for boring 304-MS was described as: 

0 to 6 inches – dark brown sand with some organic matter

 1 to 3 feet – light brown till - sandy and poorly sorted with some clay

 4 to 8 feet – light brown medium sand. 

Malcolm Pirnie drilled two borings within 20 feet on either side of boring 304-MS.  No fill was found in either boring.  Boring J1050 was described as containing: 

0 to 1 foot – brown to red brown silty fine – medium sand with trace gravel

 1 to 2.1 feet - dark brown medium sand with some fine gravel, subround

 2.1 to 3 feet - red brown fine – medium sand. 

Boring J1055 had 0.7 feet of topsoil underlain by red brown medium coarse sand with little fine-medium gravel. 

The findings from both investigations suggest that localized deposits of disturbed soil fill occur as a result of filling/grading for road construction sub-base.  Occasional detections of these materials in the rights-of-way in close proximity to the roadways cannot be inferred to be contiguous. 

The initial sampling program for investigating potential isolated fill areas in the SI Work Plan selected 49 properties for subsurface borings.  Twenty-eight of these properties were selected to “provide additional geographic coverage of the NPP study area.”  No fill was found on 18 of these properties.  The other properties were selected based on previous investigations and reports of potential indicators of fill.  As a result of the iterative process used during the whole course of this investigation, over 400 borings were drilled on 102 properties and 35 distinct isolated fill areas were identified covering parts of 70 properties.  All of these isolated fill areas have been sufficiently delineated.  Data gaps defined in previous reports have been addressed. 

The characteristics of the isolated fill areas suggest that they did not result from the same systematic filling of the contiguous fill areas by industrial quantities of waste and refuse fill.  Their generally small size, thinness, scattered locations on elevated land, co-location with some roadways, and disturbed soil composition (typically with minor coal, white ash, and non-combustible debris) suggests that they resulted primarily from minor grading/filling for road construction/maintenance, land development, and/or post-development disposal of locally derived materials.   Such activity is endemic to historic land use in any older suburban area and would have taken place regardless of the nearby contiguous filling. 

The transition from agricultural to residential development of the NPP study area began in the late 19th century, when heating with coal was the norm.  Domestic garbage and trash was routinely incinerated in coal-fired home boilers or in back yard burn pits resulting in waste ash mixed with non-combustible materials (metal, glass, ceramics) that were commonly buried very locally, typically in low areas of farm fields, residential backyards, behind outbuildings, or within vegetation along property lines.  This widespread activity resulted in local deposits of disturbed soil fill with minor amounts of materials and SOCs similar to those found in the contiguous fill, but unrelated to it.

Mixtures of various borrowed soil, sandy gravel, and crushed stone used for grading are found in many of the larger isolated fill areas, particularly underlying the larger formerly commercial parcels or crossing the property lines of subsequent housing parcels, such as in blocks K and S.  Because they cross many property boundaries, such activity must have taken place before or in conjunction with land development to make the topographic grade more suitable for farming or building.  Thin deposits of disturbed soil fill with very local deposits of concentrated ash may represent local domestic disposal pits subsequent to the development of these areas.  They contain minor amounts of materials and SOCs similar to those found in the contiguous fill, but are unrelated to it.

Roadways and their bordering rights-of-way were originally unpaved, graded locally with fill, and probably routinely tarred or oiled (potentially with coal tar) for dust suppression and covered with ash or cinders to melt snow.  Eventually they became pathways for buried utilities and their associated disturbance and filling, and later paved and curbed with crushed stone, asphalt, and concrete.  Snowplowing creates a deposit of sand, asphalt fragments, and debris onto the adjacent land.   All of these activities result in the presence of disturbed soil with minor amounts of materials and SOCs similar to those found in the contiguous fill but unrelated to it.  The asphalt used in paving both roads and driveways throughout the NPP Study Area is believed to be one of the sources of the compounds detected in borings where no fill material was found.  Asphalt is produced from the distillation of crude oil or coal tar and is used as the binder mixed with aggregates during the paving process.  Asphalt is known to contain several PAHs.  Concentrations of benzo(a)pyrene in asphalt range from 0.7 to 3.7 mg/kg for petroleum based asphalt and 2,100 to 15,170 mg/kg for coal tar based asphalt.[1]  Samples collected from depths between 0 and 3 feet below grade within the vicinity of asphalt driveways or roads may reflect surficial deposits of pollutants related to asphalting, and should not be used to uniquely identify the presence of fill.

The detailed results from the four rounds of groundwater sampling throughout the NPP study area were presented in the Supplemental Investigation Report and Remedial Action Plan dated March 2005 (November and February rounds), and the addendum to this report dated October 2005 (May and August rounds).  From these results, the following general conclusions were made.  As the reports stated, the groundwater quality appears to be only slightly degraded relative to upgradient wells.  The following SOCs were found in the groundwater above RSR criteria:

§         Chloroform has exceeded groundwater protection criteria (GWPC) in up to 9 wells and exceeds residential groundwater volatilization criterion (RGWVC) at 4 wells.  It is not an SOC associated with fill.

§         Extractable total petroleum hydrocarbons (ETPH) were detected at different contiguous fill areas and exceed GWPC at 8 wells. 

§         Chlordane and dieldrin exceed GWPC where detected, and the concentrations at upgradient well S2001S exceed their SWPC.  These compounds were detected below reporting limits in wells R2001S and NH-499-MW (within fill areas), and the results were estimated (flagged “J”). 

§         The zinc concentration at well BT-113 in the Bryden Terrace contiguous fill area exceeds SWPC.  Neither location is near the downgradient edge of the site.

§         PAH concentrations in 4 wells, including 2 downgradient wells, slightly exceed their SWPC and detection limit. 

 

Despite detections of SPLP lead above GAPMC in the fill, lead in groundwater is below groundwater protection criteria (GWPC) of the RSR. 

Chloroform is listed above as an SOC exceeding GWPC in a maximum of 9 wells throughout the four rounds of sampling, and exceeding RGWVC in 4 wells.  Chloroform detections did not appear to consistently correlate to the known fill areas.  For example, in the August 2005 sampling round, the highest detected concentrations were within wells K2001S and K2002D (31 ug/l and 48 ug/l, respectively), which are located upgradient of the known fill areas.  Additionally, chloroform was not detected in any of the fill samples analyzed for VOCs during the soil investigations within the NPP study area.  The source of the chloroform detected in groundwater is unknown, but could be related to releases from public drinking water supplies throughout the NPP study area.  Studies since 1974 have concluded that chloroform is one of four VOCs (THMs) that are commonly produced as a by-product of the chlorination treatment process.  Chlorine introduced to natural drinking water reacts with the organics within the water to form chlorinated VOCs such as chloroform, dibromochloromethane, bromodichloromethane, and bromoform (Sawyer/McCarty/Parkin, 1994).  Thus, it is possible that leaky water mains or over watering from lawn irrigation have introduced chloroform to the surrounding groundwater. 

A similar conclusion can be drawn from the detected pesticide concentrations.  A maximum of 4 wells contained concentrations of pesticides exceeding RSR criteria.  There is no unique correlation between these detected pesticides and the areas of known fill.  For example, in the May 2005 sampling event, the highest concentrations of pesticides were detected in well S2001S located upgradient of the Newhall Street Contiguous Fill Area.  Chlordane and dieldrin were detected at 0.6 ug/l and 0.39 ug/l, respectively.  Both compounds were detected just above the reporting limits of 0.54 ug/l and 0.11 ug/l, respectively.  Although concentrations of pesticides were also detected within the fill areas, the upgradient detections within the groundwater suggest no unique correlation to the fill.  Similar inconsistencies were found in the soil and fill analysis results as well.  Of the 231 total fill samples analyzed for pesticides, a total of 112 (48%) contained detected concentrations of one or more pesticides.  Of the 130 native soil samples analyzed for pesticides, 38 (30%) contained detected concentrations of one or more pesticides.  This shows that pesticides were detected in both fill and native soil, both inside and outside of known fill areas.  The detection of pesticides in both areas suggests that the pesticide residues resulted from activities in both areas unrelated to the filling such as surficial applications to fields, lawns, wetlands (either directly or via runoff), and landscaping.

 


4.0           CONCLUSIONS

The Supplemental Investigation accomplished all the objectives set forth in the approved Work Plan and the study area is considered sufficiently characterized to support remedial decisions and remedial design. 

With data gathered from 96% of the properties in the study area, the CSM is considered complete and representative of actual conditions.  Conclusions for the few properties where access was not granted were inferred from the results from neighboring properties.  Data from various sources are in agreement, successfully predicting the presumed conditions, and the results are appropriate for comparison to RSR criteria.  The DQOs resolved the data gaps such that conditions can be logically explained to the stakeholders, and a remedial action plan can be chosen.

The nature and extent of the fill material has been established. With regard to nature, the analytical results indicate that the contiguous fill and most of the isolated fill areas have substance concentrations exceeding RSR criteria, including both RDEC and GAPMC.  Non-compliant concentrations are found throughout the fill volume indicating that any portion has the potential to exceed RSR criteria.  The principal SOCs (arsenic, lead, SPLP lead, PAHs, and ETPH) are indicators for non-compliance for the fill because only 7 samples of fill out of 839 samples are non-compliant only for other SOCs.  The principal SOCs are intrinsic to the fill matrix and occur in all other fill areas and in all three fill types.  However, non-compliant isolated fill was not found on the following properties:  319 Goodrich St., 321 Goodrich St., 69 Marlboro St., 80 Marlboro St., 634 Newhall St., 28 Prospect St., 34 Prospect St., and 1002 Winchester Ave.

With regard to extent (quantity and configuration), the five major contiguous fill areas have been mapped in enough detail to locate the edge on any property within about 20 feet and estimate the area, which is approximately 29 acres.  The thickness is understood well enough to estimate the volume, which is approximately 300,000 cubic yards.  The volume of contiguous fill to a depth of four feet is approximately 150,000 cubic yards.

 

Thirty-five isolated fill areas were found and most have been mapped to the same precision as the contiguous fill.  The total area of isolated fill areas is approximately 3 acres with an average fill thickness of 2.3 feet.  Total volume of isolated fill is approximately 9,000 cubic yards. 


5.0           REMEDIAL ACTION PLAN

A thorough review of all the data furnished by the agencies, the other party’s investigations, Olin’s voluntary Initial Investigation, and Olin’s Supplemental Investigation, identifies the volume of fill at approximately 309,000 cubic yards in the NPP study area.  About 219 properties are at least partially underlain by this fill.  The Remedial Action Plan in section 5.0 of the SI report discusses remediation options to achieve compliance with the RSR.  Sheet 10 has been revised to indicate which properties in the NPP study area are to be included in the recommended remedies.  The 131 properties shaded green have some type of fill on at least a portion of the property at depths generally less than four feet and are recommended to be included in Alternative 1.  The 88 properties shaded rose have fill present at depths greater than four feet on most of the property and are recommended to be included in Alternative 2.  No need for a remedy has been identified for the remaining 84 properties.  Table 5-10 lists the properties where no fill was found and the justification why a remedy is not proposed.  For the recommended remedy, which calls for excavation of fill from the contiguous areas down to a maximum depth of four feet, and excavation of fill from the isolated areas, the estimated volume of fill to be excavated is approximately 159,000 cubic yards.

 



[1]   Grosenheider, K. E., et al, “A Review of the Current Literature Regarding Polycyclic Aromatic Hydrocarbons in Asphalt Pavement”, University of Minnesota, Mn/DOT Contract No. 81655.