West Oakland Lead Removal Assessment Report rd2 · Maximum reported lead concentration in soil:...

09:002693.2052.01RA

West Oakland Lead Removal AssessmentFinal Report

Oakland, Alameda County, California

TDD No.: TO2-09-09-09-0001Project No.: 002693.2052.01RA

February 2010

Prepared for:

U.S. ENVIRONMENTAL PROTECTION AGENCYRegion 9

Prepared by:

ECOLOGY AND ENVIRONMENT, INC.Superfund Technical Assessment and Response Team

1940 Webster Street, Suite 100Oakland, California 94612

Contract: EP-S5-08-01

SDMS DOCID# 1128238

West Oakland Lead Assessment i TO2-09-09-09-0001

able of ContentsTSection Page

1 Introduction ..............................................................................1-1

2 Site Background.......................................................................2-12.1 Site Location .................................................................................................... 2-12.2 Site History....................................................................................................... 2-12.3 Potential Sources of Lead Contamination........................................................ 2-1

2.3.1 South Prescott Park Property................................................................ 2-12.3.2 AMCO/DC Metals Superfund Site ...................................................... 2-22.3.3 Additional Historic Remedial Investigations/Actions.......................... 2-22.3.4 Other Point Source Emitters................................................................. 2-32.3.5 Lead from Vehicle Exhaust.................................................................. 2-32.3.6 Imported Fill......................................................................................... 2-32.3.7 Lead-Based Paint.................................................................................. 2-4

3 Field Activities..........................................................................3-13.1 START Field Procedures ................................................................................. 3-13.2 XRF Analysis Procedures ................................................................................ 3-2

4 Analytical Results ....................................................................4-14.1 Data Quality ..................................................................................................... 4-1

4.1.1 Field XRF Data Quality Control .......................................................... 4-14.1.2 Laboratory Data Quality Control ......................................................... 4-2

4.2 XRF and Laboratory Data Correlation............................................................. 4-24.3 Discussion of Results ....................................................................................... 4-3

4.3.1 Block 1 Results..................................................................................... 4-44.3.2 Block 2 Results..................................................................................... 4-44.3.3 Block 3 Results..................................................................................... 4-44.3.4 Block 4 Results..................................................................................... 4-54.3.5 Block 5 Results..................................................................................... 4-54.3.6 Block 6 Results..................................................................................... 4-54.3.7 Block 7 Results..................................................................................... 4-6

5 Conclusions and Recommendations......................................5-1

6 Report References ......................................................................1

Table of Contents (cont.)

West Oakland Lead Assessment ii TO2-09-09-09-0001

Appendices

A: Figures (NOT INCLUDED – PRIVACY)

B: Photographs (NOT INCLUDED – PRIVACY)

C: Tables

D: Laboratory Analytical Reports and Data Validation Reports for Confirmatory SoilSamples

E: Field Documentation (NOT INCLUDED – PRIVACY)

West Oakland Lead Assessment iii TO2-09-09-09-0001

ist of Abbreviations and AcronymsLAMCO AMCO Chemical CorporationBART Bay Area Rapid Transitbgs below ground surfaceCERCLIS Comprehensive Environmental Response, Compensation, and Liability

Information SystemDTSC California Department of Toxic Substances ControlDQOs Data Quality ObjectivesE & E Ecology and Environment, Inc.ERS Emergency Response SectionFOSC Federal On-Scene CoordinatorFP Fundamental ParameterGIS Geographic Information SystemGPS Global Positioning SystemHASP Health and Safety PlanHRS Hazard Ranking Systemmg/kg milligram per kilogramNIST National Institute of Standards and TechnologyNPL National Priorities ListPb Leadppm part per millionPST Pacific Strike TeamQA Quality AssuranceQC Quality ControlQATS Quality Assurance Technical Supports LaboratoryRSL Regional Screening LevelSAP Sampling and Analysis PlanSOP Standard Operating ProcedureSRM Standard Reference MaterialSTART Superfund Technical Assessment and Response TeamUSEPA United States Environmental Protection AgencyXRF X-Ray Fluorescence

West Oakland Lead Assessment 1-1 TO2-09-09-09-0001

1 IntroductionThe United States Environmental Protection Agency (USEPA) Region 9 Emergency ResponseSection (ERS) tasked Ecology and Environment, Inc.’s (E & E’s) Superfund TechnicalAssessment and Response Team (START) to perform a removal assessment in the SouthPrescott residential neighborhood in Oakland, Alameda County, California (Figures 1 and 2,Appendix A (NOT INCLUDED - PRIVACY)).

The removal assessment was initiated in response to public and regulatory concern over elevatedconcentrations of lead (Pb) in residential surface soils. These concerns arose as a result of a 2007remedial investigation of the AMCO chemical (AMCO) National Priorities List (NPL) site,which identified lead contamination within residential surface soils. During 2007, USEPAconducted soil excavations at nine residential properties located immediately adjacent to the NPLsite along Third and Center Streets due to elevated lead concentrations.

This removal assessment extends the scope of the 2007 remedial action to focus on themagnitude and extent of lead in residential surface soils (0-6 inches below ground surface (bgs))throughout the seven block project area in West Oakland (Figure 2 (NOT INCLUDED -PRIVACY)). Data from this assessment will be used by the USEPA Region 9 ERS to determinewhether environmental hazards are present at the site that pose “imminent and substantialendangerment to human health or the environment”. As appropriate, the USEPA will useassessment data to evaluate the potential for a removal action at the site and identify alternativesto mitigate environmental hazards that meet endangerment criteria.

Assessment activities were performed in accordance with the site-specific Sampling andAnalysis Plan (SAP), Data Quality Objectives (DQOs) and Health and Safety Plan (HASP),developed by E & E START as part of the project planning phase. The SAP, DQOs, and HASPare available under a separate cover (Sampling and Analysis Plan, West Oakland ResidentialLead Sampling, September 2009).

The START was specifically tasked to perform the following activities during this assessment:

Collect surface soil samples;

Conduct field analysis of soil samples with an X-ray fluorescence (XRF) unit;

Document the concentration of lead within residential surface soils at all samplinglocations;

Identify lead contamination in surface soils above the USEPA Regional Screening Level(RSL) of 400 milligrams per kilogram (mg/kg);

Map the site and sampling activity areas using global positioning systems (GPS) andgeographic information systems (GIS);

Perform a correlation study using data generated from the Innov-X SystemsTM XRF andfrom the USEPA Region 9 laboratory in Richmond, California; and

Prepare a final Removal Assessment Report.


2 Site Background

2.1 Site LocationThe West Oakland project area is located in the City of Oakland, Alameda County, California.The site is situated approximately one mile west of downtown Oakland and immediately southand southwest of the West Oakland Bay Area Rapid Transit (BART) rail line (Figure 1, SiteLocation Map (NOT INCLUDED - PRIVACY)).

The area of concern includes approximately seven blocks of residential houses and yards(approximately 23 acres); bounded by Center Street to the east, Third Street to the south, PeraltaStreet to the west, and the BART rail line to the north. (Figure 2, Assessment Area Map, (NOTINCLUDED - PRIVACY)). The geographic coordinates for the approximate center of the area ofconcern are Longitude 122°17'49.692"West and Latitude 37°48'14.958"North.

2.2 Site HistorySite history relating to the project area was reviewed in order to determine if lead concentrationsthat are present in urban environments can be attributed to human-made, non-AMCO sitesources. The West Oakland project area, also known as the South Prescott neighborhood, wasinitially developed during the late 1800’s as a mix of residential and commercial properties builtlargely by railroad workers. Many of the early homes, in which exterior lead-based paint waspotentially used, are still present. Since the late 1800’s, the project area has been occupied by orbordered industrial sites, where contamination is known to be present or has been remediated. Inaddition, the project area has been historically bordered by roadways and the former CypressFreeway viaduct. Each of these historic practices and/or operations may have contributed to leadin surface soils within the West Oakland project area and are discussed in further detail below.

2.3 Potential Sources of Lead ContaminationAs a result of mixed historical land use in the West Oakland project area over long periods oftime, a number of contributing sources for lead in soil are possible. A number of sites in theproject area are known to be or to have been contaminated with lead. One or more of the knowncontaminated sites could be the source or a contributing source to lead contamination detected inthe West Oakland project area. Other potential sources or contributing sources of lead includepoint source emitters, historic vehicle exhaust, imported fill and lead-based paint on structures.

2.3.1 South Prescott Park PropertyRemediation of lead in soil has been performed at a number of properties adjacent to the WestOakland project area. The majority of adjacent property located immediately south of ThirdStreet in what is now the South Prescott Park and 880 Freeway footprint was previouslyremediated. A historical document search from the California Department of Toxic SubstancesControl (DTSC) Envirostor website (www.envirostor.dtsc.ca.gov/) revealed that five individualproperties, south of Third Street, were remediated due to known contamination, including leadcontamination. Approximately 258,000 square feet of total soil surface associated with theseproperties was capped and deed restrictions were placed on the properties to protect public health

2. Site Background


(Figure 5, Historic Soil Removal Actions, (NOT INCLUDED - PRIVACY)). The following leadconcentrations were documented on the properties south of Third Street (currently South PrescottPark) prior to remediation:

Property: Former Bobo’s Wrecking Yard/Best FertilizerMaximum reported lead concentration in soil: 5,800 parts per million (ppm)Source of data: Geomatrix, 1997

Property: Union Pacific Railroad (UPRR) rail yardMaximum reported lead concentration in soil: 12,000 ppmSource of data: Geomatrix, 1997

Property: Smith’s Wrecking YardMaximum reported lead concentration in soil: 740 ppmSource of data: Environmental Solutions, Inc., 1995

Property: Railroad Property at 1509/1513 3rd StreetAverage reported lead concentration in soil: 4,110 ppmSource of data: Environmental Resources Management, 2000

Property: Prescott Park Soundwall CorridorMaximum reported lead concentration in soil: 8,740 ppmSource of data: OGISO Environmental, 1997

Prior to remediation, lead in soils at these sites may have been dispersed throughout all or part ofthe West Oakland project area.

2.3.2 AMCO/DC Metals Superfund SiteIn 2007, USEPA conducted an investigation of the potential dispersion of lead contamination inresidential surface soils from historic operations at the AMCO chemical NPL site located at 1414Third St. in Oakland, California. The NPL site was formerly a chemical distribution facilityoperated by AMCO Chemical Corporation between the 1960's and 1989. The AMCO facilityincluded a railroad spur, above ground tanks and drums, and underground storage tanks used totransfer and store raw materials. From 1989 to November 1998, the site was operated as a scrapmetals yard by DC Metals, Inc. (DC Metals). In November 1998, all metal scrap and equipmentwas removed from the site by the operator and all site operations ceased. The site wassubsequently leased to Cable Moore, Inc. and is currently being used for cable storage.

The 2007 USEPA-funded remedial investigation included residential properties locatedimmediately adjacent to the NPL site along the north side of Third St. and the east side of CenterSt. Results from this investigation provided evidence of lead in residential surface soils atconcentrations up to 2,700 mg/kg, which exceed the USEPA RSL of 400 mg/kg. These elevatedlead concentrations prompted USEPA to excavate soil at nine residential properties located alongThird and Center Streets in 2007 (URS, 2007 and URS, 2008). Locations of the 2007 residentialsoil removal actions are provided under Appendix A, Figure 3.

2.3.3 Additional Historic Remedial Investigations/ActionsIn May 1997, DTSC identified leaking drums and containers, stained soils, and chemical odors at528 Lewis Street during a drive-by assessment. The 528 Lewis Street property was identified as

2. Site Background


a 0.19-acre vacant lot which was formerly used as a junkyard for storing vehicles, used tires, andgas cylinders (Figure 5, (NOT INCLUDED - PRIVACY)). Based on preliminary assessmentresults and the USEPA Hazard Ranking System (HRS), 528 Lewis Street was identified as apotential hazardous site and entered into the DTSC Calsites database and the ComprehensiveEnvironmental Response, Compensation, and Liability Information System (CERCLIS) on June9, 1997. On November 9, 2001 DTSC conducted soil sampling at the Lewis St. property.Analytical results from this sampling event revealed a maximum concentration of 1,080 mg/kgfor lead in soils. The site was excavated from 1 to 4 feet bgs in March 2004 to remove lead andother metals contamination. After excavation, confirmatory samples were collected and resultswere below the cleanup level of 260 mg/kg.

The U. S. Postal Service Oakland Main distribution facility located at the southwest corner of 7th

Street and Peralta Street was built in 1969, but was a residential area prior to that development(Figure 6, Adjacent Land Use, (NOT INCLUDED - PRIVACY)). A preliminary endangermentassessment performed at the U.S. Postal Service Main distribution facility documented themaximum lead concentration in soil at the site was 540 ppm; however, samples were notcollected from above 2 feet bgs (Weston, 1994).

2.3.4 Other Point Source EmittersA point source emitter is a fixed site from which a contaminant emanates. It is commonlyobserved that lead concentrations in soil are higher in urban areas and in heavily industrializedareas. Though it may be difficult to pinpoint a single point source for lead in urban and/orindustrial areas, the presence of large military and industrial properties up-wind from the WestOakland project area could be a contributing source for lead in soil resulting from aerialdeposition of lead in particulates. Additionally, the adjacent industrial sites (referenced above)which required remedial actions can be considered significant point-source emitters.

2.3.5 Lead from Vehicle ExhaustBefore tetraethyl lead was banned for use as a performance additive to gasoline, exhaust fromgasoline fueled vehicles caused aerial deposition of lead in particulates near roadways andfreeways. The former Cypress Freeway viaduct was located along the current alignment ofMandela Parkway north of 7th Street with a curve to the east leading to an alignment parallel to5th Street. Due to the distance of the former Cypress Freeway viaduct from the West Oaklandproject area, historic leaded gasoline emissions are likely to be a significant contributing sourcefor lead accumulation in residential soils within the project area.

2.3.6 Imported FillPrior to initial development of the South Prescott neighborhood in the late 1800’s, the tidalmargin of San Francisco Bay extended to just south of 3rd Street in the project area. The marginboundary was irregular and extended further north in some areas (California Department ofConservation, 2003). Following development of the residential neighborhood, the bay marginwas filled before construction of the rail yard and other industrial sites roughly south and west ofthe current 880 Freeway. The source of imported fill is not known, and it may have containedlead contaminated soil. While it is possible that many of the properties in the South Prescottneighborhood were not filled, it is likely that irregular areas of fill exist at some properties wheretidal channels were present before development.

2. Site Background


2.3.7 Lead-Based PaintBefore lead was banned for use in most paints, exterior paint commonly used on homescontained lead. Two mechanisms for lead-based paint contributing to soil lead have beenidentified. Because paint is designed to naturally chalk, weathering of exterior lead-based paintmay cause it to crumble or peel, and the resulting paint chips and particles then contaminate thesurrounding soil. Abatement of the paint using scraping or sandblasting techniques (withoutcollection devices) may also result in lead contamination of the soil. Age of residence issometimes used as an indicator for the presence of lead-based paint. The use of lead in exteriorhouse paint has markedly declined since the 1940s. In the 1970s, it was virtually banned fromuse in residential paints. Thus, older homes and residential developments such as those present inthis study area, which are more likely to contain lead-based paint, pose an additional hazard tolead accumulation in residential soils.


3 Field ActivitiesThe field investigation phase of the project was performed from September 19 through 27, 2009,under the authority of Federal On-Scene Coordinator (FOSC) Steve Calanog. One to fourSTART members were on site during all field activities. In addition, the United States CoastGuard Pacific Strike Team (PST) provided assistance during field activities. Generally, oneSTART member operated the XRF in the field laboratory and two sampling teams includingSTART and PST members completed field tasks; specific field tasks are discussed in furtherdetail in Section 3.1. START also compiled site data into the USEPA’s Response Managerdatabase. Photographic documentation of START activity is provided in Appendix B (NOTINCLUDED – PRIVACY).

All START site activities were conducted according to the SAP. Specific START field activitiesat the site consisted of:

Documentation of site conditions through logbook entries and photographicdocumentation;

Collection of surface soil samples and XRF analysis of these samples for characterizationof lead contamination in residential surface soils;

Collection of surface soil samples for confirmatory laboratory analysis (USEPA Method6010C); and

A GPS survey for documentation of sample locations and structures related to the projectarea.

3.1 START Field ProceduresThe START followed all pre-determined standard operating procedures (SOPs), as outlined inthe site SAP, for sample collection and documentation procedures during the field investigationphase of this project. This section provides a summary of specific field procedures used to ensureaccurate assessment data.

Surface soil samples were collected from individual residential land parcels to characterize leadconcentrations within residential soils. For the purposes of this assessment, an individualresidential land parcel includes properties that contain single and multi-family dwellings,apartment complexes, vacant lots, playgrounds and parks. Prior to conducting any samplingactivity, access permission was obtained from the property owner by the USEPA FOSC.Sampling of some planned parcels was not possible due to the property owner denying access ornot responding to access requests.

In order to allow for better delineation, residential parcels were divided into separate decisionunits: front yard, back yard, and side yard decision units. In many planned decision unitspavement, debris, structures such as storage sheds and fencing constituted barriers to samplingsuch that one or more planned decision units was not available for a particular parcel.

Composite samples were collected from all decision units. Surface composite samples consisted offive discrete aliquots collected 0-6 inches bgs, in which four aliquots were collected 5 to 15 feet

3. Field Activities


from a single mid-point where GPS coordinates were collected and recorded. A fielddocumentation sheet was completed at each sample location that included: the parcel address,sample number, date, time, a relative sketch of sample location(s) and parcel structures,photograph numbers, and GPS coordinates (Appendix E, Field Documentation).

Each composite sample collected was given a unique identifier containing a prefix indicating thestreet block (i.e. Block 1 (B1)), followed by the specific house number, and a final letterindicating the surface area in which the sample was collected; front yard (F), back yard (B), orside yard (S). Where field duplicate composite samples were collected, a zero was added withinthe sample identifier, immediately following the prefix indicating the street block. Therefore, afiled duplicate located on block 1 would be labeled as B10 and followed by the remainingsample identifier.

Composite samples were collected by sample teams wearing clean nitrile gloves and usingdedicated disposable plastic trowels and then placed into a clean plastic zip-lock bag forhomogenization and holding. After collection each sample was individually labeled with itsunique sample number and delivered to XRF personnel for sample preparation. Upon receipt forsample preparation, samples were recorded in a sample log (Appendix E, Field Documentation,(NOT INCLUDED - PRIVACY)). If a sample was received that was wet, an aliquot of at least30-grams was placed in a sample boat or on a coffee filter and then dried in a toaster oven.Samples were homogenized in the sample bag by kneading, crushing, and shaking the soil forapproximately two minutes. After homogenization samples were passed through a #60 meshsieve to remove large particles. The sieved sample was transferred into a new pre-labeledpolyethylene cup and covered with Mylar® film. After sample preparation, samples weredelivered to the field laboratory for XRF analysis. All non-dedicated sample handling devices(i.e. sieves, transfer spoons) were decontaminated after each use according to the site SAP SOP(E & E SOP #3.15).

3.2 XRF Analysis ProceduresDuring this field assessment, a total of 90 individual composite soil samples were analyzed byusing an Innov-X Systems field portable XRF unit operated in accordance with the manufacturesguidance and USEPA SW-846 Method 6200, including Quality Assurance/Quality Control(QA/QC) procedures.

Before operation of the XRF each day, the unit was allowed the manufacturer-recommendedwarm up time of 25-30 minutes. The XRF unit was then subjected to an initial calibration thatincluded energy calibration and resolution check and standard reference material (SRM)analysis. The standard reference material used for XRF calibration was obtained from theNational Institute of Standards and Technology (NIST) and referenced as NIST 2711 whenanalyzed. Once calibrated, two second source control standards and a sand blank sample wereanalyzed to determine instrument performance. In addition to instrument performance checks,sand blank samples were prepared and analyzed by XRF at the end of each set of 20 site soilsamples to monitor for cross-contamination. Sand blank samples were ground with a mortar andpestle, and then prepared by following the same preparation method and using the same samplepreparation equipment as for site soil samples.

3. Field Activities


One out of every ten site samples was selected for preparation duplicate analysis. Preparationduplicates were collected by splitting a single site sample, after homogenization and sievingoccurred, and then preparing two separate sample aliquots for XRF analysis. Preparationduplicates were labeled and recorded with a “PD” following the corresponding sample identifierfor identification.

The energy calibration and resolution check analysis, standard reference material sampleanalysis, control standard sample analysis, and sand blank sample analysis used for XRFcalibration, performance, and quality control are discussed under Section 4.1 (Field XRF DataQuality Control) of this report.

All XRF sample analyses were performed in the intrusive mode with a 180 second count time formeasurement, within a designated field laboratory (USEPA Method 6200, 1998). Each samplewas analyzed one time and the corresponding lead concentration was recorded in the site XRFlogbook. Lead concentrations for all soil samples analyzed XRF are presented in Appendix C,Table 1 and Appendix E, Field Documentation.


4 Analytical ResultsDuring this assessment, 90 surface soil composite samples were collected from 54 parcels withinthe project area and subjected to XRF analysis. A sample location results map for surface soilcomposite samples analyzed by XRF is provided in Appendix A, Figure 4. In addition, five fieldduplicate surface soil composite samples, 13 preparation duplicates and six sand blank sampleswere analyzed by XRF for quality control objectives. An XRF data summary is provided inAppendix C, Table 1.

A total of 20 confirmation samples were submitted to the USEPA Region 9 laboratory inRichmond, California for total lead analysis (USEPA Method 6010C). A laboratory data summaryis provided in Appendix C, Table 2 and complete laboratory analysis and data validation reportsare provided in Appendix D.

4.1 Data QualityDuring the West Oakland lead removal assessment, efforts were made to ensure that the qualityof all data generated through XRF and laboratory analyses met appropriate established USEPAcriteria. A discussion of XRF and laboratory data quality control efforts is provided below.

4.1.1 Field XRF Data Quality ControlTo provide QC for the field analytical effort, USEPA SW-846 Method 6200 was adhered toduring XRF sample analysis. Each sample was prepared carefully, homogenized thoroughly,placed into appropriate XRF analysis containers, and analyzed as an independent sample(Section 3.1 and 3.2). The concentration of the obtained sample analyte was reported.

Effective energy fundamental parameters (FP) calibration was performed during this fieldanalytical effort to ensure quality control of the XRF unit. Effective energy FP relies on pureelement standards, standard reference material standards, and control standard samples.

To determine whether the XRF instrument was within resolution and stability tolerances, anenergy calibration check was run with a pure manganese element standard at the beginning ofeach day as the first XRF analysis, at any time which the instrument detected that thecharacteristic x-ray lines were shifting, and at the end of each work day. To check the accuracyof the instrument and to assess the stability and consistency of analyses for the analyte of interest(lead) a SRM sample (NIST 2711) was analyzed at the beginning of each day, after each set of20 site samples, and at the end of each work day. The measured value for each SRM run duringfield XRF analysis for the project was within ±20 percent standard deviation of the true valueand considered acceptable.

Two types of blank samples were analyzed to provide quality control for XRF analysis:instrument blanks and method blanks. Blank samples were obtained from “clean” silica sand andwere free of lead at concentrations above the method detection limit.

An instrument blank sample was used to verify that no contamination existed on theprobe window during XRF analysis. The instrument blank sample was analyzed at thebeginning of each day, after each set of 20 site samples, and at the end of each work day.

4. Analytical Results


No lead concentrations above the method detection limits were found during instrumentblank sample analyses.

Method blank samples were used to monitor for sample preparation-inducedcontaminants or interferences. Each method blank sample was prepared by following thesame preparation procedure as the site soil samples. Method blank samples wereanalyzed after each set of 20 site samples. No lead concentrations above the methoddetection limits were found during method blank sample analyses.

A precision and accuracy study was conducted using control standard samples to determine thereliable detection limits of the XRF equipment. The study was performed by analyzing twoUSEPA Quality Assurance Technical Supports Laboratory (QATS) control samples (Sample ID213 and Sample ID 374) ten separate times with the XRF and calculating the average. Bothcontrol samples were then submitted to the USEPA Region 9 laboratory for total lead analysis.The calculated average from XRF analysis, laboratory analytical result, and the trueconcentration provided by QATS laboratory were compared for both control sample ID 213 andcontrol sample ID 374 to determine the precision and accuracy of the XRF unit.

Control sample ID 213 had a true concentration of lead of less than 1 mg/kg. The leadconcentration determined using field the field XRF was less than 4 mg/kg. Laboratory results forControl sample ID 213 were less than 3 mg/kg for lead. Because the concentration ofControl sample ID 213 was less than the instrument detection limit, it was not useful toward thecalculation of the method detection limit. The data from analysis of Control sample ID 213documented the XRF instrument detection limit to be 4 mg/kg. Control sample ID 213 wasanalyzed at the beginning of each day, after each set of 20 site samples, and at the end of eachwork day.

Control sample ID 374 was also used to verify accuracy of detections from XRF analyses thatwere near the USEPA RSL of 400 mg/kg. Both XRF analyses and laboratory analyses confirmedthat Control sample ID 374 was at a concentration slightly above the 400 mg/kg. Control sampleID 374 was analyzed at the beginning of each day, after each set of 20 site samples, and at theend of each work day.

The data used in detection limit and performance verification studies are presented in theAppendix C, Table 5.

4.1.2 Laboratory Data Quality ControlConfirmatory samples were analyzed by the USEPA Region 9 laboratory. Once data wasgenerated by the USEPA laboratory, a data review was completed, and the laboratory data wasvalidated using the Region 9 Draft Superfund Data Evaluation/Validation Guidance (USEPA2001). Data validation indicated the laboratory data was acceptable without qualification asdefinitive data.

4.2 XRF and Laboratory Data CorrelationUSEPA SW-846 Method 6200 suggests that a minimum of 5 to 10 percent of the XRF-analyzedsamples be submitted to an analytical laboratory for confirmatory analysis to verify the quality ofthe XRF data. Out of the 90 composite soil samples collected for XRF analysis for site



characterization, 20 samples (21 percent) were submitted to the USEPA Region 9 laboratory forconfirmatory analysis (USEPA Method 6010C).

From the 20 samples selected for confirmatory analysis, six XRF-analyzed samples were lessthan 300 mg/kg, five XRF-analyzed samples were between 300 mg/kg and 800 mg/kg, and nineXRF-analyzed samples were greater than 800 mg/kg. The validated laboratory results of theconfirmatory analysis and XRF analyses were then evaluated with a least squares linearregression analysis, which provided a correlation coefficient (R2) and slope (y). The finalcorrelation coefficient for laboratory versus XRF results was 0.8604 (86.04%) with a slope of0.8764x. Therefore, XRF data collected for this assessment meets the criteria for use asscreening level data (R2=0.7). The laboratory and XRF results used for the data correlation studyare summarized in Appendix C, Table 3 and the least squares linear regression analysis isprovided in Appendix C, Table 4.

4.3 Discussion of ResultsData collected during this assessment was evaluated to determine if residential surface soilswithin the project area contain lead at levels above or below the USEPA RSL and to define anynoticeable lead contaminant deposition patterns. Site data from both XRF and laboratory analysiswere compared to the April 2009 USEPA RSL for lead in residential soils of 400 mg/kg.

A total of 90 samples (excluding duplicates) were collected from within the project area; a totalof 54 parcels, consisting of 90 decision units, were sampled. The parcels sampled representapproximately 33 percent of the areal extent of the West Oakland study area. Leadconcentrations documented in the study area ranged from 68 mg/kg to 2,510 mg/kg. For thestudy area, sample concentrations by range were:

Lead less than 400 mg/kg – 18 samples Lead from 400 to 799 mg/kg – 29 samples Lead from 800 to 1,199 mg/kg – 25 samples Lead in excess of 1,200 mg/kg - 18 samples

The concentration of lead exceeded the RSL in 72 (80 percent) of the samples; the averageconcentration of lead in samples from the study area was 843 mg/kg. Lead concentrationsexceeding the RSL were documented in every block sampled in this assessment; however, theredoes not appear to be any pattern associated with the contamination that is attributable tohistorical potential sources identified in the study area.

Fifteen parcels were identified in this study from which samples containing lead concentrationsin excess of 1,200 mg/kg (greater than 3 times the RSL) were collected. These properties are:323 Center Street; 331, 338 and 356 Chester Street; 1488 and 1492 3rd Street; 355, 506, and 515Henry Street; 1518, 1555, 1566 and 1579 5th Street; 322 and 324 Peralta Street.

To determine if any noticeable deposition patterns exist within the project area, XRF results wereevaluated for each residential block.



4.3.1 Block 1 ResultsIn the Block 1 area, 24 decision unit samples were collected from 17 parcels. The sampledparcels represent approximately 52 percent of the areal extent of Block 1. Lead concentrations inBlock 1 samples ranged from a low of 284 mg/kg to 2,455 mg/kg. The number of samples byconcentration range was:

Lead less than 400 mg/kg – 3 samples Lead from 400 to 799 mg/kg – 4 samples Lead from 800 to 1,199 mg/kg – 10 samples Lead in excess of 1,200 mg/kg – 7 samples

Concentrations of lead exceeded the RSL in 21 of the samples (87.5 percent) from Block 1. Theaverage lead concentration in samples from the block is 994 mg/kg, which exceeds the RSL.There is no apparent pattern to or gradient of lead concentrations in this block; leadcontamination appears to be relatively evenly distributed throughout the block.


Lead less than 400 mg/kg – 2 samples Lead from 400 to 799 mg/kg – 9 samples Lead from 800 to 1,199 mg/kg – 8 samples Lead in excess of 1,200 mg/kg – 1 sample

Concentrations of lead exceeded the RSL in 18 of the samples (90 percent) from Block 2. Theaverage lead concentration in samples from the block is 736 mg/kg, which exceeds the RSL.There is no apparent pattern to or gradient of lead concentrations in this block; leadcontamination appears to be relatively evenly distributed throughout the block.






4.3.4 Block 4 ResultsIn the Block 4 area, 8 decision unit samples were collected from 4 parcels. The sampled parcelsrepresent approximately 15 percent of the areal extent of Block 4. Lead concentrations in Block4 samples ranged from a low of 357 mg/kg to 1,798 mg/kg. The number of samples byconcentration range was:

Lead less than 400 mg/kg – 1 sample Lead from 400 to 799 mg/kg – 3 samples Lead from 800 to 1,199 mg/kg – 1 sample Lead in excess of 1,200 mg/kg – 3 samples


4.3.5 Block 5 ResultsIn the Block 5 area, 6 decision unit samples were collected from 3 parcels. The sampled parcelsrepresent approximately 14 percent of the areal extent of Block 5. Lead concentrations in Block5 samples ranged from a low of 254 mg/kg to 1,778 mg/kg. The number of samples byconcentration range was:

Lead less than 400 mg/kg – 2 samples Lead from 400 to 799 mg/kg – 1 samples Lead from 800 to 1,199 mg/kg – 1 sample Lead in excess of 1,200 mg/kg – 2 samples




Concentrations of lead exceeded the RSL in 8 of the samples (61.5 percent) from Block 6. Theaverage lead concentration in samples from the block is 684 mg/kg, which exceeds the RSL.



There is no apparent pattern to or gradient of lead concentrations in this block; leadcontamination appears to be relatively evenly distributed throughout the block.

4.3.7 Block 7 ResultsIn the Block 7 area, 3 decision unit samples were collected from 1 parcel. The sampled parcelsrepresent approximately 25 percent of the areal extent of Block 7. Lead concentrations in Block7 samples ranged from a low of 297 mg/kg to 976 mg/kg. The number of samples byconcentration range was:

Lead less than 400 mg/kg – 2 samples Lead from 400 to 799 mg/kg – 0 samples Lead from 800 to 1,199 mg/kg – 1 sample Lead in excess of 1,200 mg/kg – 0 samples

Concentrations of lead exceeded the RSL in 1 sample (33.3 percent) from Block 5. The averagelead concentration in samples from the block is 541 mg/kg, which exceeds the RSL. There is noapparent pattern to or gradient of lead concentrations in this block; lead contamination appears tobe relatively evenly distributed throughout the block.


5 Conclusions and RecommendationsConclusions and recommendations reached from the lead removal assessment are providedbelow.

The XRF and confirmatory laboratory results indicate that lead exceeds the USEPA RSLof 400 mg/kg in surface soils throughout the project area. Although lead was found to bepresent within the project area surface soils, conclusions about the source ofcontamination cannot be determined from this assessment. Further evaluation may beneeded to determine whether or not surface soil lead concentrations within the projectarea are consistent with lead concentrations in nearby areas, and lead concentrationswithin urban settings.

A background concentration for lead in surface soils should be established for the projectarea. To provide a correlation between the project area and the typical Oakland,California urban setting, additional surface soil sampling for lead should be performedoutside the project area.

Based on current residential land use of the project area, surface soils that were found tocontain lead above the USEPA RSL may require additional evaluation and/or sampling tocompletely determine the potential exposure risks and pathways. A more immediateevaluation of potential exposure risks and pathways may be considered for residentialparcels where lead concentrations exceeded 1,000 mg/kg. Sensitive populations (i.e.children) along with everyday use should be considered when evaluating parcels thatexceeded 1,000 mg/kg for lead.

An appropriate risk assessment model, such as the USEPA Integrated Exposure UptakeBiokinetic Model for Lead in Children (IEUBK), may be considered to determine theexposure risks and pathways of lead in surface soils at parcels which exceed 400 mg/kg.

Bioavailability sampling within the project may be considered to characterize thephysical and chemical character of lead and determine the degree to which lead inresidential soils is available for uptake in potentially exposed persons. Ingestion accountsfor most of the lead taken into the blood when exposure occurs by both ingestion andbreathing lead. For this reason, the extent to which lead is absorbed from the digestivetract is an important factor in lead exposure and lead toxicity.

West Oakland Lead Assessment 1 TO2-09-09-09-0001

6 Report ReferencesCalifornia Department of Conservation. 2003. “Seismic Hazard Zone Report for the Oakland

West 7.5-Minute Quadrangle, Alameda County” 2003

California Department of Transportation District 4. 2001. “South Prescott Neighborhood ParkRemediation Completion Report” May 2001

Department of Toxic Substances Control (DTSC). 2002. “Preliminary Assessment SamplingReport, Lewis Property, 528 Lewis Street, Oakland California” June 2002

Ecology and Environment, Inc. (E & E) 2009. Sampling and Analysis Plan, West OaklandResidential Lead Sampling, (SAP). September 2009

Environmental Resources Management (ERM), 2000. “Removal Action Completion Report,1509/1513 Third Street, Oakland, California” July 2000

Environmental Solutions, Inc. 1995. “Final Report of Findings Smith Wrecking Yard ProposedSouth Prescott Park, Oakland, California” June 1995

Geomatrix. 1997. “Remedial Investigation and Baseline Risk Assessment Report I-880Realignment Corridor, West Oakland and Desert Rail Yards, Oakland, California” July1997

OGISO Environmental. 1997. “Site Remediation Completion Report Cypress “B” FreewayReconstruction Project Prescott Park Soundwall Project, Oakland, California”December 1997

URS, Corporation (URS). 2007. “Emergency Response and Time Critical Quality AssuranceSampling Plan, 3rd Street and Center, Oakland, CA” June 2007

URS, Corporation (URS). 2008. “Figure X, Mean Pb Concentrations in PPM Before and AfterRemoval Actions, AMCO Chemical Superfund Site” January 2008

U.S. EPA, 2007. Office of Solid Waste Method 6200 - Field Portable X-Ray FluorescenceSpectrometry for the Determination of Elemental Concentrations in Soil and Sediment,February 2007

U.S. EPA, 2009. Regional Screening Levels (RSLs) for Chemical Contaminants, April 2009

Weston, Inc. 1994. “Preliminary Endangerment Assessment Investigation for Proposed FreewayAlignment Parcel C, Oakland Post Office, Oakland, California” August 1994

West Oakland Lead Assessment A-1 TO2-09-09-09-0001

Appendix A:Figures

(NONE OF THE FOLLOWING FIGURES WERE INCLUDED IN THIS APPENDIX -PRIVACY)

Figure 1 Site Location Map

Figure 2 Assessment Area Map

Figure 3 Locations of 2007 USEPA Residential Soil Removal Action

Figure 4 West Oakland Lead Removal Assessment Sample Results

Figure 5 Historic Soil Removal Actions

Figure 6 Adjacent Land Use


Appendix B:Photographs

No photos have been provided for this section – Privacy.


Appendix C:Tables

Table 1 XRF Data Summary (Lead)

Table 2 Laboratory Data Summary (Lead)

Table 3 Laboratory and XRF Data Correlation Study Results (Lead)

Table 4 Least Squares Linear Regression Analysis

Table 5 XRF Detection Limit and Performance Verification Results

Table 1. XRF Data Summary (Lead)West Oakland Lead Removal Assessment,

Oakland, Alameda County, CaliforniaTDD No.: TO2-09-09-09-0001 Project No.: 002693.2052.01RA

Lead (Pb)

400 (mg/kg)

Sample ID Address Sample Date Block ID

Field XRF Analysis

Result (mg/kg)B1-323-S 323 Center 22-Oct-09 B1 632B1-323-B1 323 Center 22-Oct-09 B1 1467B1-323-B2 323 Center 22-Oct-09 B1 1420B1-337-B 337 Center 19-Oct-09 B1 806B1-347-B 347 Center 19-Oct-09 B1 674B1-355-B 355 Center 20-Oct-09 B1 949B1-357-B 357 Center 19-Oct-09 B1 857B1-1453-F 1453 5th 19-Oct-09 B1 469B1-1453-B 1453 5th 19-Oct-09 B1 619B1-1469-B 1469 5th 20-Oct-09 B1 873B1-VL1-F 1495 5th 19-Oct-09 B1 302B1-VL1-B 1495 5th 19-Oct-09 B1 388B1-360-B 360 Chester 19-Oct-09 B1 836B1-356-B 356 Chester 19-Oct-09 B1 1689B1-342-B 342 Chester 20-Oct-09 B1 1145B1-338-B 338 Chester 19-Oct-09 B1 1465B1-326-F 326 Chester 20-Oct-09 B1 988B1-326-B 326 Chester 20-Oct-09 B1 912B1-322-F 322 Chester 20-Oct-09 B1 284B1-1492-F 1492 3rd 20-Oct-09 B1 829B1-1492-B 1492 3rd 20-Oct-09 B1 2455B1-VL3-F 1488 3rd 21-Oct-09 B1 1689B10-VL3-F* 1488 3rd 21-Oct-09 B1 1075B1-VL3-B 1488 3rd 21-Oct-09 B1 1219B1-1484-F 1484 3rd 21-Oct-09 B1 901B2-1505-F 1505 3rd 21-Oct-09 B2 1002B2-1529-B 1529 3rd 20-Oct-09 B2 697B2-1536-F1 1536 3rd 21-Oct-09 B2 412B2-1536-F2 1536 3rd 21-Oct-09 B2 372B2-VL2-F 1506 3rd 20-Oct-09 B2 480B2-VL2-B 1506 3rd 20-Oct-09 B2 630B2-Park-F 319/321 Chester 20-Oct-09 B2 68B2-327-F 327 Chester 20-Oct-09 B2 736B2-331-F1 331 Chester 20-Oct-09 B2 1063B2-331-F2 331 Chester 20-Oct-09 B2 975B2-331-S1 331 Chester 20-Oct-09 B2 827B2-331-S2 331 Chester 20-Oct-09 B2 1378B2-331-B1 331 Chester 20-Oct-09 B2 821B2-331-B2 331 Chester 20-Oct-09 B2 884B2-355-F 355 Chester 20-Oct-09 B2 757B2-355-B 355 Chester 20-Oct-09 B2 893B2-350-F 350 Henry 21-Oct-09 B2 539B2-332-B 332 Henry 21-Oct-09 B2 558B2-316-F 316 Henry 20-Oct-09 B2 791B2-316-B 316 Henry 20-Oct-09 B2 841B3-321-B 321 Henry 27-Oct-09 B3 637B3-323-B 323 Henry 27-Oct-09 B3 1107B3-325-B 325 Henry 27-Oct-09 B3 1162B3-331-B 331 Henry 27-Oct-09 B3 519B3-351-B 351 Henry 21-Oct-09 B3 519

Residential USEPA RSL



Lead (Pb)

400 (mg/kg)


Field XRF Analysis

Result (mg/kg)


B3-355-F 355 Henry 21-Oct-09 B3 672B3-355-B1 355 Henry 21-Oct-09 B3 1237



Lead (Pb)

400 (mg/kg)


Field XRF Analysis

Result (mg/kg)


B3-355-B2 355 Henry 21-Oct-09 B3 1065B30-355-B2* 355 Henry 21-Oct-09 B3 1016B3-VL4-F 1561 5th 22-Oct-09 B3 501B3-VL4-B 1561 5th 22-Oct-09 B3 838B3-1555-B 1555 5th 22-Oct-09 B3 1339B3-1579-F 1579 5th 21-Oct-09 B3 2345B3-350-B1 350 Lewis 21-Oct-09 B3 239B3-350-B2 350 Lewis 21-Oct-09 B3 162B3-344-S 344 Lewis 21-Oct-09 B3 339B3-344-B 344 Lewis 21-Oct-09 B3 793B4-345-B 345 Lewis 23-Oct-09 B4 656B4-353-F 353 Lewis 23-Oct-09 B4 479B4-353-S 353 Lewis 23-Oct-09 B4 357B4-353-B1 353 Lewis 23-Oct-09 B4 646B4-353-B2 353 Lewis 23-Oct-09 B4 863B40-353-B2* 353 Lewis 23-Oct-09 B4 468B4-324-F 324 Peralta 23-Oct-09 B4 1745B4-324-B 324 Peralta 23-Oct-09 B4 1798B4-322-B 322 Peralta 23-Oct-09 B4 1327B5-1518-B 1518 5th 22-Oct-09 B5 1778B5-506-S1 506 Henry 21-Oct-09 B5 954B5-506-S2 506 Henry 21-Oct-09 B5 1450B5-514-S1 514 Henry 22-Oct-09 B5 262B5-514-S2 514 Henry 22-Oct-09 B5 784B5-514-B 514 Henry 22-Oct-09 B5 254B6-GADREN-F 1582 5th 21-Oct-09 B6 276B6-GARDEN-B 1582 5th 21-Oct-09 B6 493B6-1566-B 1566 5th 21-Oct-09 B6 1255B6-1550-F 1550 5th 22-Oct-09 B6 360B6-1550-S 1550 5th 22-Oct-09 B6 766B6-1550-B 1550 5th 22-Oct-09 B6 333B6-515-B 515 Henry 22-Oct-09 B6 2510B60-515-B* 515 Henry 22-Oct-09 B6 1565B6-519-B 519 Henry 22-Oct-09 B6 643B6-529-F 529 Henry 22-Oct-09 B6 522B6-529-B1 529 Henry 22-Oct-09 B6 185B60-529-B1* 529 Henry 22-Oct-09 B6 149B6-529-B2 529 Henry 22-Oct-09 B6 579B6-537-F 537 Henry 22-Oct-09 B6 326B6-537-B 537 Henry 22-Oct-09 B6 655B7-GARDEN-1 533 Lewis 21-Oct-09 B7 976B7-GARDEN-2 533 Lewis 21-Oct-09 B7 297B7-GARDEN-3 533 Lewis 21-Oct-09 B7 350

Notes:

mg/kg = milligrams per kilogram

RSL = U.S. EPA Regional Screening Level, Residential Soils, Lead, 400 mg/kg

* = Field Duplicate Sample

Bold Results = Exceeds U.S. EPA Regional Screening Level, Residential Soils (400 mg/kg)

Table 2. Laboratory Data Summary (Lead)West Oakland Lead Removal Assessment,


Lead (Pb)

400 (mg/kg)

Notes:


B7



B3

B3

B3

B4

B2

B2

B3

B3

B1

B1

B1

B2

B1

B1

B1

B1

B1-323-B1 323 Center St. 22-Oct-09 1400

B1-VL3-F 1488 3rd St. 21-Oct-09 950

B10-VL3-F 1488 3rd St. 21-Oct-09 1400

170

150

760

B7-GARDEN-1 533 Lewis St. 21-Oct-09 860

B6

B6

B6

900

990

1200

50

440

2000

140

B6-1550-B 1550 5th St. 22-Oct-09

USEPA Region 9

Laboratory Result (mg/kg)

1300

540

290

260

710

370

B6-529-B1 529 Henry St. 22-Oct-09

B60-529-B1 529 Henry St. 22-Oct-09

B4-322-B 322 Peralta St. 23-Oct-09

B30-355-B2 355 Henry St. 21-Oct-09

B30-355-B2 (PD) 355 Henry St. 21-Oct-09

B3-1579-F 1579 5th St. 21-Oct-09

B3-350-B2 350 Lewis St. 21-Oct-09

B2-PARK-F 319/321 Chester St. 20-Oct-09

B3-VL4-F 1561 5th St. 22-Oct-09

B2-331-S1 331 Chester St. 20-Oct-09

B2-1536-F1 1536 3rd St. 21-Oct-09

B1-VL1-F 1495 5th St. 19-Oct-09

B1-VL1-F (PD) 1495 5th St. 19-Oct-09

B1-338-B 338 Chester St. 19-Oct-09

B1-1453-B 1453 5th St. 19-Oct-09



Table 3. Laboratory and XRF Data Correlation Study Results (Lead)West Oakland Lead Removal Assessment,


Notes:


Field XRF Analysis

Result (mg/kg)

400 (mg/kg)

Lead (Pb)

1465

619

1467

302

315

1689



1075

827

412

68

501

2345

162B3

B3

B3

B4

B2

B2

B3

B3

B1

B1

B1

B2

B1

B1

B1

B1

B1-323-B1 323 Center St. 22-Oct-09 1400

B1-VL3-F 1488 3rd St. 21-Oct-09 950

B10-VL3-F 1488 3rd St. 21-Oct-09 1400

1016

985

1327

185

149

333

976


170

150

760

B6

B6

B6

B7-GARDEN-1 533 Lewis St. 21-Oct-09 860B7

900

990

1200

50

440

2000

140

B6-1550-B 1550 5th St. 22-Oct-09

USEPA Region 9

Laboratory Result

(mg/kg)

1300

540

290

260

710

370

B6-529-B1 529 Henry St. 22-Oct-09

B60-529-B1 529 Henry St. 22-Oct-09

B4-322-B 322 Peralta St. 23-Oct-09

B30-355-B2 355 Henry St. 21-Oct-09

B30-355-B2 (PD) 355 Henry St. 21-Oct-09

B3-1579-F 1579 5th St. 21-Oct-09

B3-350-B2 350 Lewis St. 21-Oct-09

B2-PARK-F 319/321 Chester St. 20-Oct-09

B3-VL4-F 1561 5th St. 22-Oct-09

B2-331-S1 331 Chester St. 20-Oct-09

B2-1536-F1 1536 3rd St. 21-Oct-09

B1-VL1-F 1495 5th St. 19-Oct-09

B1-VL1-F (PD) 1495 5th St. 19-Oct-09

B1-338-B 338 Chester St. 19-Oct-09

B1-1453-B 1453 5th St. 19-Oct-09


Table 4. Least Squares Linear Regression AnalysisWest Oakland Lead Removal Assessment,


Notes:

R2 = Correlation Coefficient

mg/kg = milligram per kilogram

XRF = X-Ray Fluorescence

Pb = Lead element symbol (contaminant of concern)

y = 0.8764x

R2 = 0.8604

0

500

1000

1500

2000

2500

0 500 1000 1500 2000 2500

XRF Field Screening Data

US

EP

AR

egio

n9

La

bo

rato

ryD

ata

Series1

Linear (Series1)

Table 5. XRF Detection Limit and Performance Verification ResultsWest Oakland Lead Removal Assessment,


Sample ID XRF Analysis Date XRF Result Pb Sample ID XRF Analysis Date XRF Result Pb

213 20-Oct-2009 <4 374 20-Oct-2009 436.46

213 20-Oct-2009 <4 374 20-Oct-2009 446.11

213 20-Oct-2009 <4 374 20-Oct-2009 450.11

213 20-Oct-2009 <4 374 20-Oct-2009 455.88

213 20-Oct-2009 <4 374 20-Oct-2009 439.64

213 20-Oct-2009 <4 374 20-Oct-2009 440.03

213 20-Oct-2009 <4 374 20-Oct-2009 443.65

213 20-Oct-2009 <4 374 20-Oct-2009 448.6

213 20-Oct-2009 <4 374 20-Oct-2009 452.85

213 20-Oct-2009 <4 374 20-Oct-2009 452.41

Sample ID Lab Analysis Date Lab Result Pb Sample ID Lab Analysis Date Lab Result Pb

213 21-Oct-2009 <3 mg/kg 374 21-Oct-2009 410 mg/kg

Sample ID Analysis Date True Value Pb Sample ID Analysis Date True Value Pb

213 18-Oct-2009 <1 mg/kg 374 18-Oct-2009 400 to 450 mg/kg

Notes:

<4 mg/kg

1True Values

1 True values for Lead in control samples provided by QATS laboratory at purchase

XRF Data

Laboratory Data (6010C)

374 Mean Result = 446.57 mg/kg213 Mean Result =

Appendix D:Laboratory Analytical Reports and

Data Validation Reports for Confirmatory Soil Samples


Appendix E:Field Documentation

(NOT DOCUMENTATION WAS INCLUDED IN THIS APPENDIX- PRIVACY)

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