2020_01_Phase_II_Sampling_Report_(125_Coral_Street).pdf

Weber, Hayes & Associates Hydrogeology and Environmental Engineering

120 Westgate Drive, Watsonville, CA 95076

(831) 722-3580 // www.weber-hayes.com

Phase II Environmental Site Assessment Soil and Soil Vapor Sample Screening for a Commercial Property Transaction

January 23, 2020

Subject Site:

125 Coral Street Santa Cruz, California

Santa Cruz County Assessor Parcel Numbers (APNs):

008-17-124, 008-17-125

PROJECT: 2X936

Prepared for:

City of Santa Cruz Economic Development c/o: Bonnie Lipscomb 337 Locust Street

Santa Cruz, California http://www.weber-hayes.com/

125 Coral Street, Santa Cruz ii

Table of Contents

1.0 EXECUTIVE SUMMARY

1.1 Summary of Completed Field Work & Laboratory Analysis

1.1.1 Summary of Field Observations

1.1.2 Summary of Laboratory Results

1.2 Summary of Phase II ESA Conclusions and Recommendations

2.0 BACKGROUND

2.1 Site Location:

2.2 Subsurface Soil and Groundwater Conditions

2.3 Previous Environmental Investigation

3.0 FIELD WORK & LABORATORY RESULTS

3.1 Soil Sampling

3.1.1 Results of Soil Sampling (Table 1 & 2)

3.2 Soil Vapor Sampling

3.2.1 Results of Soil vapor Sampling (Table 3)

4.0 CONCLUSIONS & RECOMMENDATIONS

iii

Figures, Tables & Appendices

Figures

Figure 1: Location Map

Figure 2: Site Map & Sample Locations

Figure 3: Soil Vapor Results Figure

Figure 4: Soil Results Figure

Tables & Charts

Table 1: Summary of Soil Sample Analytical Results –TPH & VOCs

Table 2: Summary of Soil Sample Analytical Results – CAM 17 Metals

Table 3: Summary of Soil Vapor Analytical Results – TPH and VOCs

Appendices

Appendix A: Field Documentation including - Field Notes, Geologic Logs, Photo Sheets, & Field Methodologies

Appendix B: State Certified Laboratory Reports – Soil and Soil Vapor Samples

2X936/2020_01_Phase II Sampling Report (Coral Street) 1

Weber, Hayes & Associates Hydrogeology and Environmental Engineering

120 Westgate Drive, Watsonville, CA 95076

(831) 722-3580 // www.weber-hayes.com

1.0 EXECUTIVE SUMMARY

This Phase II Soil and Soil Vapor Assessment report provides follow-up soil and soil vapor sampling and laboratory testing results at the subject 0.64-acre, subject property is located at 125 Coral Street in Santa

Cruz (see Location Map, Figure 1).

This commercial property screening program was designed to confirm the presence or absence of potential environmental liabilities associated with Recognized Environmental Conditions1 identified in a recently completed Phase I Environmental Site Assessment (Phase I ESA)2. Historical land use records obtained as part of the Phase I ESA documented commercial operations at the property over the last 70 years including a bakery (circa 1950s) and a metal fabrication business (circa 1960s to the present). The current round of soil and soil vapor sampling was designed to specifically evaluate the following two (2)

Recognized Environmental Conditions:

1. Long-term Outdoor Material and Vehicle Storage: Historical land use records and aerial photos documented the long-term storage of vehicles and operational materials along the eastern perimeter and back lot of the Site. Most of the storage was on native dirt, which can potentially impact shallow soils, so Phase II shallow soil sampling was recommended to confirm no significant contaminant concentrations are present.

2. Outdoor (in-ground) Vehicle Hoist: An in-active, outdoor, in-ground hydraulic vehicle hoist was observed along the eastern perimeter of the Site (see Site Map, Figure 2). The hoist is located beneath a large boat stored along the eastern side of the building and reportedly has not been used in years. In ground hoists have some potential to leak hydraulic fluid to the subsurface, so

Phase II soil coring and sampling was recommended to confirm no significant contaminant concentrations are present.

1.1 Summary of Completed Field Work & Laboratory Analysis

The Phase II sampling and testing program was designed to evaluate whether potential historical or recent chemical releases are present at concentrations indicative of a significant environmental liability. To assess the potential liabilities identified in the Phase I ESA, A total of six (6) soil samples and three (3) soil vapor samples were collected and laboratory analyzed for contaminants of potential concern (see Sample

Location Map, Figure 2).

1.1.1 Summary of Field Observations

An experienced field geologist logged the soil types and specifically noted any chemical staining or odors and a calibrated photoionization detector (PID) was used in the field to measure total volatile organic

1: The term “recognized environmental conditions”, is defined as “the presence or likely presence of any hazardous substances or petroleum products in, on, or at a property: (1) due to release to the environment; (2) under conditions indicative of a release to the environment; or (3) under conditions that pose a material threat of a future release to the environment” (ASTM Standard E 1527-13)

2: Weber-Hayes & Associates report: Phase I Environmental Site Assessment (125 Coral Street, Santa Cruz), September 16, 2019.

http://www.weber-hayes.com/ compounds (TVOCs) at each soil coring location (Appendix A). There was no evidence of contamination observed at any of the sample locations. Field documentation, photographs, and geologic logs are included in Appendix A for reference.

1.1.2 Summary of Laboratory Results

Soil and soil vapor samples were submitted to a State-certified laboratory for analysis and the lab report is included as Appendix B. Samples and laboratory detections are presented in plan view on Figures 3 (soil vapor) and 4 (soil) and tabulated results are summarized on Tables 1 through 3. The tables include risk-based, regulatory-established screening threshold limits that are used to provide an initial evaluation on whether detected contaminant concentrations pose a potential, unacceptable risk to human health and safety, or the environment3,4. Screening limits are established for both: a) commercial land use risks, and

b) unrestricted (residential) land use risks. The State-certified laboratory results of tested soil and soil vapor samples revealed the following:

3: Environmental Screening Levels (ESLs): Established to address potential risk associated with a number of, potential contaminant transport pathways including risk to human health, risk to ecological resources (terrestrial habitat), and risk to groundwater (leaching). These ESLs are intended to provide quantitative risk-based guidance on whether further assessment or remediation of contamination is warranted based on land use (commercial v. residential). See table notes for additional details.

4: California DTSC Soil Screening Levels: Screening Levels established strictly for risk to human health. See table notes for additional details.

Subject Site (outlined in blue) and Sample Locations

• Soil Testing Results (Tables 1 & 2, Figure 4):

o Total Petroleum Hydrocarbons (TPH): Trace detections of TPH-diesel and TPH-motor oil were detected in the six (6) soil samples analyzed – there were no thresholds exceedances for either residential or commercial land use.

o Volatile Organic Compounds (VOCs): Trace to non-detect concentrations of this suite of volatile contaminant compounds were detected in the six (6) soil samples analyzed – there were no thresholds exceedances for either residential or commercial land use.

o Metals Testing Results: Except for Arsenic, all other metal concentrations were detected below established risk-based thresholds for human health (both residential and commercial land use).

▪ Arsenic: Arsenic is commonly associated with pesticide use (weed control) and as a rodenticide (rodent control). Toxicological studies have established an extremely low threshold limits for human health, at a concentration that is well below naturally-occurring/background levels. Regulatory agencies, however, do not require cleanup of metals if they are considered naturally-occurring/background levels. Multiple studies in the Santa Cruz County region show that naturally-occurring Arsenic concentrations typically fall within range of 4-to-12 mg/kg, All five (5) surface samples soil samples (0.5-ft below ground surface, bgs) contained elevated concentrations of Arsenic (i.e., > 12 mg/kg). Deeper samples, collected at a depth of 2-feet bgs, decreased to naturally-occurring levels in three (3) of the five (5) locations suggesting a downward trend (see soil results, Table 2).

Note: All Arsenic concentrations are characterized as non-hazardous (i.e., <500 mg/kg) so any site soils can be disposed of at a non-haz, Class III sanitary landfill during site development earthworks (see Section 3.1 for additional details).

▪ Vanadium & Lead: There were no concentrations of Vanadium or Lead that exceeded risk-based thresholds for human health, for both residential and commercial land use agency thresholds (see Table 2). However, shallow soil samples collected from across the site contained concentrations of Vanadium and Lead that exceed new, “Terrestrial Habitat”

ESLs5 established to address a potential ecological-risk. This ecological pathway is unlikely to apply in this very urbanized, City location and it is highly unlikely that any further characterization or cleanup would be required. See Vanadium at all locations, and Lead at two (2) locations (see Table 2 & Section 3.1 for additional details).

• Soil Vapor Testing Results (Table 3): Subsurface soil gas samples were collected at three (3) soil vapor locations and analyzed for Volatile Organic Compounds (VOCs) via EPA Method TO-15.

o Volatile Organic Compounds: The three (3) subsurface soil gas samples targeted potential high risk land use locations including a storm drain, the receiving/loading dock, and a long term materials storage area to screen for potential sources of vapor intrusion. There were

5: “Terrestrial Habitat” thresholds were recently established (Jan 24, 2019) to address the potential impacts of urban contaminants to the ecological pathway.

only a limited number of detections in the TO-15 suite of 78 common, volatile urban contaminants compounds (see Summary of Soil Gas Results, Table 3). Trace levels of the volatile fuel constituent compounds were detected at two locations, specifically:

▪ Benzene slightly exceeded the residential land use threshold of 3.2 ug/m3 at two locations

(i.e., 11 ug/m3 at the loading dock, and 8.9 ug/m3 at the materials storage location).

▪ Ethylbenzene slightly exceeded the residential land use threshold of 37 ug/m3 at one location (i.e., 11 ug/m3 at the loading dock, and 160 ug/m3 at the materials storage location).

The source of these soil gas detections could easily be attributed to plume off-gassing from a historic fuel release site originating upgradient (north) and across Coral Street6.

1.2 Summary of Phase II ESA Conclusions and Recommendations

Field observations supported by laboratory analytical results indicate that there is no evidence that a significant chemical release has occurred at the subject site. Data shows there are some elevated concentrations of Arsenic in shallow soil that exceed risk-based, human health threshold limits but appear to be limited vertically and if needed, can be disposed of at a local, Class III (non-hazardous) landfill. The presence of Benzene and Ethylbenzene at low concentrations but at levels that exceed residential land use thresholds could warrant including a standard of care, vapor barrier as part of any new construction design.

It is our opinion, that there is no evidence of a significant chemical release at the subject site based on field observations during soil core drilling and laboratory results of representative soil and soil vapor samples. However, there are some limited impacts in shallow soil (arsenic) that will warrant soil removal of some shallow surface soils, which can be most cost effectively completed during property redevelopment (i.e., earthworks preparation for the foundation). In addition, the very low concentrations of Benzene and Ethylbenzene could warrant including a standard of care, vapor barrier as part of any new construction design.

Agency Notification: Overall, there are a limited number of soil and soil vapor samples that exceed agency-established, risk-based thresholds that are established to evaluate potential risks to various receptors (human health, ecologic). As noted above, it is our opinion that these exceedances are limited.

The Santa Cruz County Environmental health Services (SCC-EHS) is the regulatory agency responsible for protection of human health and the environment regarding hazardous materials and chemical releases to soils. The County of Santa Cruz has an established Duty to Report7 requirement that mandates they be notified when contamination is discovered in order to provide third party evaluation of the results and conclusions. Accordingly, a copy of this report should be forwarded to SCC-EHS for their review and to confirm they agree with our conclusions.

This concludes the Executive Summary.

6: The Santa Cruz Petroleum fuel leak site (GeoTracker Case #T0608799974):

• https://geotracker.waterboards.ca.gov/profile_report.asp?global_id=T0608799974

7 : Santa Cruz County Code 7.100.2705 (Duty to Report)

• http://www.codepublishing.com/CA/SantaCruzCounty/html/SantaCruzCounty07/SantaCruzCounty07100.html#7.100.270 https://geotracker.waterboards.ca.gov/profile_report.asp?global_id=T0608799974 http://www.codepublishing.com/CA/SantaCruzCounty/html/SantaCruzCounty07/SantaCruzCounty07100.html#7.100.270

2.0 BACKGROUND

2.1 Site Location:

The subject property (the “Site”) consists of two parcels on Coral Street in Santa Cruz. The property spans a total area of approximately 0.64-acres.

The Site has been developed since at least 1905 according to available records.

The Site has been occupied by the same entity since at least 1960 (Sea Berg

Metal Fabricators, Inc.). The earliest historical land use map, dated 1886, shows the Site as undeveloped land which remained the same until at least

1892. The Site was developed sometime between 1892 and 1905 as a residential home with a separate garage unit. The Site was redeveloped mostly into its current configuration sometime between 1956 and 1964.

The L-shaped, subject Site (see clip below) is situated in a mixed, light industrial-residential area of Santa

Cruz and is bordered by commercial businesses to the north and west, and social service operations (Santa

Cruz County of Homeless Center) to the east and south.

2.2 Subsurface Soil and Groundwater Conditions

The site is located on the northern edge of California’s Monterey Bay, approximately 0.5 miles northwest of Point Santa Cruz, a broad, shallow sloping marine terrace at the base of the Santa Cruz Mountains. The site is underlain by mixed marine and non-marine terrace deposits of the Pleistocene age. The marine deposits are largely a mix of sands and gravels deposited during historic sea-level regressions and are reported to have a maximum thickness of approximately 40 feet thick. Non-marine deposits include areas of fluvial and colluvial silts, sands, and gravels.

A nearby, monitored fuel release site located approximately 200 feet northwest of the subject Site documented that underlying soils consist primarily of sand with silt from 0 to 15 ft below ground surface

(bgs), sands and gravels between 15 and 21 ft bgs, and poorly graded sand below 21 ft bgs. Groundwater has historically fluctuated at this nearby site from depths of 7 to 15 ft bgs and groundwater flow direction has been documented to generally flow towards the southeast. Groundwater was not encountered during this investigation in any borings which reached a maximum depth of nine (9) feet below ground surface.

2.3 Previous Environmental Investigation

Phase I Environmental Site Assessment (2019): Weber, Hayes and Associates completed a Phase I

Environmental Site Assessment to identify the potential presence of environmental liabilities at the

Subject Site (looking southward) Property boundary shown by dashed blue line subject site.8 The report reviewed historical and current land uses as well as agency reports and files associated with the property and suggested a Phase II sampling program based on two environmental concerns. The two concerns were based on the following discoveries: long term storage of materials, equipment, and vehicles on native dirt, and an inactive outdoor inground hydraulic hoist.

3.0 FIELD WORK & LABORATORY RESULTS

Weber, Hayes, and Associates (WHA) was contracted to investigate the concerns identified in the Phase I

ESA through soil and soil vapor sampling at select locations throughout the property (see Sample Location

Map, Figure 2). Groundwater was to be sampled only if field evidence of contamination was encountered during drilling, however there was no evidence of contamination encountered in the field at any of the boring locations and therefore groundwater was not sampled. The Phase II sampling program was designed as a preliminary screen to evaluate whether releases occurred, and whether field and laboratory testing results indicate the presence of a significant environmental liability.

All soil and soil vapor samples were submitted to a State-certified laboratory and the results were compared with regulatory-established, Environmental Screening Levels (ESL’s)2F

9, 3F

10, which are designed to provide initial evaluation on whether detected contaminant concentrations pose an unacceptable risk to human health and safety, or the environment. Tables 1 through 3 provide a summary of the lab results and established agency limits. The established screening concentration limit for individual contaminant compounds are based on land use (e.g., commercial, residential) and the receptor being protected (i.e., human heath, and/or ecological). All tabulated laboratory analytical results include screening limits established for both: a) commercial land use risks, and

b) unrestricted (residential) land use risks. We completed the following tasks for this Phase II ESA.

3.1 Soil Sampling

Soil sampling was conducted by Weber, Hayes and

Associates field staff in accordance with our Field

Methodology for Shallow Soil Sampling and Hydraulic

Driven Probe Sampling (see Appendix A). Seventeen

(17) soil samples were collected from six (6) locations across the site to evaluate the potential presence/magnitude of a chemical release and provide

8: Weber, Hayes, and Associates: Phase I Environmental Site Assessment (125 Coral Street, Santa Cruz), September 16, 2019.

9: Environmental Screening Levels (ESLs): Regional Water Quality Control Board (San Francisco Bay Region) guideline document: Screening for Environmental Concerns at Sites with Contaminated Soil and Groundwater (Final version, 2019).

The ESLs are intended to provide quantitative risk-based guidance on whether further assessment or remediation of contamination is warranted based on impacts to potential receptors and for different land uses (commercial v. residential).

<https://www.waterboards.ca.gov/sanfranciscobay/water_issues/programs/ESL/new/ESL_Summary_Tables_24Jan19_Rev1.pdf

10: CA DTSC Soil Screening Levels: From the California Department of Toxic Substances Control (DTSC), Office of Human and Ecological Risk (HERO), Human Health Risk Assessment (HHRA) Note Number 3, Table 1, June 2018. If no DTSC screening level is established, then the corresponding US EPA RSL is provided.

Inspection of Continuous Soil Cores file://///WHAFILESERVER01/d/AJOB/AJOB/2x913.Chanticleer%20ESA%20(SCWD)/Reports/%3chttp:/www.swrcb.ca.gov/rwqcb2/water_issues/programs/ESL/ESL%20Users%20Guide_22Feb16.pdf%20%3e file://///WHAFILESERVER01/d/AJOB/AJOB/2x913.Chanticleer%20ESA%20(SCWD)/Reports/%3chttp:/www.swrcb.ca.gov/rwqcb2/water_issues/programs/ESL/ESL%20Users%20Guide_22Feb16.pdf%20%3e soil characterization data for future site development. Soil samples were continuously cored using a hydraulic driven Geoprobe and collected at various depths. Samples collected at 0.5 feet bgs were initially analyzed at all locations, and the remainder of the samples were put on hold for later analysis in the case contamination was discovered in the shallow samples.

The soil sampling strategy was designed to gather chemical information on the following:

• Long-term material, equipment, and vehicle storage

• Potential leaks from outdoor inground hydraulic hoist

Soil samples were analyzed by the following:

1) Total Petroleum Hydrocarbons as diesel and motor oil by EPA Method 8015;

2) CAM 17 Metals by EPA Method 6010b;

3) Volatile Organic Compounds by EPA Method 8260

All boring locations were properly sealed with neat cement grout following sample collection in accordance with state and local standards.

3.1.1 Results of Soil Sampling (Table 1 & 2)

State-certified laboratory results were compared with regulatory-established, Environmental Screening

Levels (ESL’s),6 which are designed to provide initial (Tier 1) evaluation on whether a detected contaminant concentration poses an unacceptable risk to human health and safety, or the environment.

Screening concentration limits for individual contaminant compound are established in look-up tables and are based on the potential land use (e.g., residential, commercial or construction worker) and receptor being protected (i.e., human heath, ecological protection, and/or nuisance). All laboratory analytical results have been compared against screening limits established for:

• Human health risk for a commercial land use, and

• Unrestricted land use (residential).

See summary tables for individual agency limits and associated compound exceedances. The State‐

Certified laboratory reports are included as Appendix B and the results are described in Section 3 of this report.

The State-Certified laboratory results revealed the following:

• Soil (Tables 1 & 2):

o TPH-Diesel, Motor Oil (Table 1): All concentrations of TPH- diesel, and motor oil were detected at trace levels and were well below ESLs.

o Metals (CAM 17 suite) (Table 2):

Except for Arsenic, all samples analyzed for metals (SS-1, SS-2, SS-3, SS-4, SS-5) contained concentrations that were below both residential and commercial risk-based screening thresholds protective of human health and safety.

-Arsenic: Naturally occurring background concentrations of Arsenic can range up to 12 mg/kg in California, which exceeds both commercial and residential land use thresholds.

However, on Site detections of Arsenic ranged from 10.4 mg/kg to 82.5 mg/kg at the 0.5 feet sample depth. Due to the elevated detections of Arsenic mostly above naturally occurring background concentrations, the deeper samples were analyzed to determine the extent of the Arsenic detections. The deeper samples showed a reduction in Arsenic concentrations in most every sample except for one location (SS-2), and concentrations ranged from non-detect to 26 mg/kg in the samples obtained at 2 feet bgs.

Samples at all five (5) locations analyzed for metals, contained concentrations that slightly exceed new, terrestrial habitat ESLs for Vanadium (ESLeco=18 mg/kg). The deeper follow up samples at 2 feet bgs resulted in concentrations very similar to the shallow sample depth results. Concentrations of Vanadium ranged from 14.4 to 58 mg/kg across the Site.

Additionally, two locations (SS-2 & SS-3) contained concentrations of Lead which also exceeded the terrestrial habitat ESL for Lead (ESLeco=32 mg/kg). However, the follow up deeper samples at SS-2 and SS-3 confirmed concentrations of Lead fell below all ESL thresholds at the 2 ft sample depth.

However, the “terrestrial habitat” ESLs are newly established (Jan 24, 2019 4F

11), ecologic risk limits do not apply to this urban, commercial site (i.e. we have evaluated the Site for applicability of the ecological “terrestrial habitat” ESLs and have determined they do not apply for this commercial Site).

o Volatile Organic Compounds (Table 1): All six (6) samples analyzed for volatile organic compounds contained detections ranging from non-detect to low trace concentrations and were all well below both residential and commercial ESL thresholds. This also includes the sample HS-1 which was taken at 9 feet bgs next to the in ground hydraulic hoist, confirming no evidence of contamination from the hoist.

▪ There was one trace detection of Naphthalene at SS-1 with a detected concentration of 0.130 mg/kg which slightly exceeded the Tier 1 ESL based on leaching with an established threshold of 0.042 mg/kg for the protection of groundwater. The deeper sample at 2 feet was analyzed and the result was non-detect. All other detected concentrations were well below ESL Tier 1 thresholds.

3.2 Soil Vapor Sampling

Three (3) temporary soil vapor probes were installed on November 25th, 2019 and subsequently sampled by Weber, Hayes and Associates field staff in accordance with our Field Methodology for Active Soil Gas

Sampling (see Appendix A). All three soil vapor probes (SV-1, SV-2, SV-3) were installed at 5 feet bgs (see geologic logs and construction diagrams in Appendix A). Soil vapor probes were properly destroyed following sampling by completely removing the sample tubing from the subsurface and sealing the surface.

All three soil vapor samples were analyzed for Volatile Organic Compounds (VOCs) by EPA Method TO-15.

The State‐certified laboratory reports are included as Appendix B.

Field documentation, photo sheets, geologic logs, and field methodology for sample collection are documented in Appendix A.

11: New ESL tables (January 24, 2019) currently have no regulatory precedence for corrective action based on new Terrestrial habitat threshold limits.

• https://www.waterboards.ca.gov/sanfranciscobay/water_issues/programs/ESL/new/ESL_Summary_Tables_24Jan19_Rev1.pdf https://www.waterboards.ca.gov/sanfranciscobay/water_issues/programs/ESL/new/ESL_Summary_Tables_24Jan19_Rev1.pdf

3.2.1 Results of Soil vapor Sampling (Table 3)

Volatile Organic Compounds: Most all VOC constituents were either trace or non-detect at all locations, however SV-2 contained a slightly elevated concentration of Benzene and SV-3 contained slightly elevated concentrations of both Benzene and Ethylbenzene. Both SV-2 and SV-3 contained concentrations of

Benzene at 11 ug/m3 and 8.9 ug/m3 respectively which slightly exceeded the residential land use threshold established at 3.2 ug/m3 however did not exceed the commercial threshold established at 14 ug/m3. The Ethylbenzene detection at SV-3 contained a concentration of 160 ug/m3 exceeding both the residential and commercial screening thresholds established at 37 ug/m3 and 160 ug/m3 respectively.

There were no other detections of any volatile organic compounds in exceedance of residential or commercial land use thresholds (see Table 3 for details).

4.0 CONCLUSIONS & RECOMMENDATIONS

Field observations supported by laboratory analytical results indicate that there is no evidence that a significant chemical release has occurred at the subject site. Data shows there are some elevated concentrations of Arsenic in shallow soil that exceed risk-based, human health threshold limits but appear to be limited vertically and if needed, can be disposed of at a local, Class III (non-hazardous) landfill. The presence of Benzene and Ethylbenzene at low concentrations but at levels that exceed residential land use thresholds could warrant including a standard of care, vapor barrier as part of any new construction design.

It is our opinion, that there is no evidence of a significant chemical release at the subject site based on field observations during soil core drilling and laboratory results of representative soil and soil vapor samples. However, there are some limited impacts in shallow soil (arsenic) that will warrant soil removal of some shallow surface soils, which can be most cost effectively completed during property redevelopment (i.e., earthworks preparation for the foundation). In addition, the very low concentrations of Benzene and Ethylbenzene could warrant including a standard of care, vapor barrier as part of any new construction design.

Agency Notification: Overall, there are a limited number of soil and soil vapor samples that exceed agency-established, risk-based thresholds that are established to evaluate potential risks to various receptors (human health, ecologic). As noted above, it is our opinion that these exceedances are limited.

The Santa Cruz County Environmental health Services (SCC-EHS) is the regulatory agency responsible for protection of human health and the environment regarding hazardous materials and chemical releases to soils. The County of Santa Cruz has an established Duty to Report requirement that mandates they be notified when contamination is discovered in order to provide third party evaluation of the results and conclusions. Accordingly, a copy of this report should be forwarded to SCC-EHS for their review and to confirm they agree with our conclusions.

Limitations

Our service consists of professional opinions and recommendations made in accordance with generally accepted geologic and engineering principles and practices. This warranty is in lieu of all others, either express or implied. The analysis and conclusions in this report are based on sampling and testing which are necessarily limited. Additional data from future work may Lead to modification of the opinions expressed herein.

All work related to this investigation and remediation at this site is done under the direct supervision of a

Professional Geologist or Engineer, registered in California, and experienced in environmental assessment and remediation.

If you have any questions regarding this report, or any aspect of this project, please contact us at (831)

722-3580.

Sincerely, Weber, Hayes and Associates

By:

And: __________________

Pat Hoban, PG Senior Geologist

Staff Scientist Shaun Ersoy

Figures

Figure 1: Location Map

Figure 2: Site Map & Sample Locations

Figure 3: Soil Vapor Results

Figure 4: Soil Results

APPROXIMATE

SHALLOW

GROUNDWATER FLOW

DIRECTION

(Based on multiple nearby monitoring well networks and regional surface water)

EXPLANATION OF SYMBOLS

Shallow Soil Samples (5 Locations) Soil Vapor Samples (3 Locations)

SSSSS---111

SSVVV---111

Storm Drain

Metal Shop Warehouse

Office Space

Lo ad in g D oc k

Material & Misc. Storage

Hydraulic Hoist (in-ground)

Long-Term Vehicle Storage

Long-Term Vehicle Storage

Adjoining Commercial Property

C oral Street

SSSSS---111

SSSSS---222

SSSSS---333

SSSSS---444

HHSSS---111

SSSSS---555

SV-1

SV-2

SV-3

SSVVV---111

SSVVV---222

SSVVV---333

SV-1

Depth 5 ft

TPH-Gas < 200

Benz <2

E.Benz <5

SV-2

Depth 5 ft

TPH-Gas < 200

Benz

E.Benz

SV-3

Depth 5 ft

TPH-Gas 6,900

Benz 8.9

E.Benz

SSSS--44

SSSS--55

Depth

0.5 ft 2 ft

Arsenic 25.2

< 0.46

Lead 21.3 1.68

Hoist Sample (HS-1) (sampled at depth of 9-ft)

Only trace TPH and Volatile Compound detections)

SSSS--33

Depth

0.5 ft 2 ft

Arsenic 24.8 2.38

Lead 68.2 9.06

SSSS--22

Depth

0.5 ft 2 ft

Arsenic 16.9 23.6

Lead 36.8 31.2

SSSS--11

Depth

0.5 ft 2 ft

Arsenic 82.5

Lead 4.99 13.8

SSSS--44

Depth

0.5 ft 2 ft

Arsenic 10.4 8.68

Lead 18.6 11.6

Tables

Table 1: Summary of Soil Sample Analytical Results – TPH & VOCs

Table 2: Summary of Soil Sample Analytical Results – Metals

Table 3: Summary of Soil Vapor Analytical Results – TPH & VOCs

Sample ID Sample Date Depth

(ft)

TPH as

DIESEL

(C12-C22)

TPH as

MOTOR OIL

(C22-C40)** Benzene Toluene Ethylbenzene Xylenes MTBE Other VOCs

SS-1 11/25/2019 0.5 2.0 9.30 < 0.0010 0.0706 < 0.0025 < 0.0065 < 0.001

Acetone = 0.0456 (J)

2-Butanone (MEK) = 0.0162 (B)

Naphthalene = 0.130

SS-2 11/25/2019 0.5 2.23 J 29.10 < 0.0010 0.026 < 0.0025 < 0.0065 < 0.001

Acetone = 0.0254 (J)

2-Butanone (MEK) = 0.0123 (B)

Naphthalene = 0.0208

SS-3 11/25/2019 0.5 2.52 J 21.60 < 0.0010 0.0882 < 0.0025 < 0.0065 < 0.001

Acetone = 0.0658 (J)

2-Butanone (MEK) = 0.211 (B)

Naphthalene = 0.0316

SS-4 11/25/2019 0.5 4.01 J 23.4 J < 0.0010 0.0430 < 0.0025 < 0.0065 < 0.001

Acetone = 0.0680 (J)

2-Butanone (MEK) = 0.181 (B)

Naphthalene = 0.0156

SS-5 11/25/2019 0.5 2.70 J 36.2 < 0.0010 0.0532 < 0.0025 < 0.0065 < 0.001

Acetone =0.0278 (J)

2-Butanone (MEK) = 0.0678 (B)

HS-1 11/25/2019 9 < 4.0 5.33 J < 0.0010 0.0672 < 0.0025 < 0.0065 < 0.001

Acetone =0.0803 (J)

2-Butanone (MEK) = 0.134 (B)

4.0 8.0 0.0010 0.005 0.0025 0.0065 0.001 varies

260 (HH) 1,600 (Eco) 0.025 (L) 3.2 (L) 0.43 (L) 2.1 (L) 0.028 (L) Acetone =0.92 (L)

2-Butanone (MEK) = 6.1 (L)

Naphthalene = 0.042 (L)

0.33 / 1.4 1,100 / 5,300 5.8 / 25 580 / 2,500 47 / 210

Acetone = 61,000 / 670,000

2-Butanone (MEK) = 27,000 / 190,000

Naphthalene = NE

Notes

BOLD = A bolden concentration indicates the laboratory detected the contaminant at the concentration shown.

BOLD = Analytical result detected at a concentration that is above the Commercial ESL.

BOLD = Analytical result detected at a concentration that is above the Residential ESL.

BOLD = Lab result was detected at a concentration that is above the most conservative Tier 1 threshold.

1 =

TIER 1 ESL =

L =

HH =

ECO =

O =

2 =

Note:

< = A "less than" symbol indicates no detectable concentrations (i.e., the laboratory did not detect the contaminant at the concentration shown).

**= (C22-C32) + (C32-C40) = the hydrocarbon motor oil value

RDL =

ND = Non Detection

'-- = Not Analyzed

J = Laboratory reports that the detection value is between MDL and RDL, and should be considered an estimate.

^ = Detection and Quantitation Limits are raised due to sample dilution

Reported Detection Limit (RDL)

Acetone = 61,000 / 670,000

2-Butanone (MEK) = NE

Naphthalene = 3.8 / 1.7 47 / 210 (4,100)

580 / 2,500

(2,400)

5.9 / 26

(540)

1,100 / 5,300

(4,700)

0.33 / 1.4

(33)

12,000 / 180,000

(54,000)

260 / 1,200

(1,100)

Environmental Screening Levels (ESLs) (1)

Direct Exposure ESL (human health risk):

Residential, Commercial and (Construction Worker) Land Use

Table 1

Summary of Soil Analytical Results

Total Petroleum Hydrocarbons (TPH), Volatile Organic Compounds (VOCs) 125 Coral Street, Santa Cruz

All soil results are in milligrams per Kilogram (mg/Kg)

Sample Information Total Petroleum

Hydrocarbons Volatile Organic Compounds (VOCs) by EPA Method 8260B

Laboratory Analytical Results

US EPA Region 9 Soil Regional Screening Levels (RSLs): From US EPA Regional Screening Levels for Soil ( https://www.epa.gov/risk/regional-screening-levels-rsls-generic-tables ) , last updated November‐2019 using the Summary Table [based on Carcinogenic Target Risk (TR) =1E‐6, Noncancer Hazard Index (HI) =1.0].

CA DTSC Soil Screening Levels: From the California Department of Toxic Substances Control (DTSC), Office of Human and Ecological

Risk (HERO), Human Health Risk Assessment (HHRA) Note Number 3, Table 1, April 2019. If no DTSC screening level is established then the corrisponding US EPA RSL is provided.

The most conservative Environmental Screening Level (ESL) across all potential pathways including leaching, human health, ecolologic ("Terrestrial Habitat"), volatilization (inhalation).

Indicates the lowest ESL is based on a potential Leaching pathway (for groundwater protection).

Indicates the lowest ESL is based on a potential Human Health & Safety Pathway (ingestion, inhalation, dermal).

Indcates the lowest ESL is based on a potential Terrestrial Habitat pathway.

Indicates the lowest ESL is based on a potential "odor nuisance" (i.e. 100 mg/kg for gasoline).

Reported Detection Limit = is the laboratory-determined value that is 2 to 5 times above the Method Detection Limit (MDL) that can be reproduced in a manner that results in a 99% confidence level and is both accurate and precise.

DTSC-Modified Screening Levels (2)

(for human health risk)

Residential or Commercial Land Use

Not Established

Environmental Screening Levels (ESLs): Regional Water Quality Control Board (San Francisco Bay Region) guideline document:

Screening for Environmental Concerns at Sites With Contaminated Soil and Groundwater (Final version, 2019). The ESLs are intended to provide quantitative risk-based guidance on whether further assessment or remediation of contamination is warranted

<https://www.waterboards.ca.gov/sanfranciscobay/water_issues/programs/esl.html >

" Tier 1 ESL " (all possible pathways & land uses)

Human Health (HH), Leachability (L), Ecologic (Eco), Odor (O)

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(ft) Antimony Arsenic (A) Barium Beryllium Cadmium Chromium Cobalt Copper Lead Mercury Molybdenum Nickel Selenium Silver Thallium Vanadium (V) Zinc

0.5 < 2.0 82.5 53.1 0.447 0.519 J 12.1 4.53 7.94 4.99 0.0945 1.98 6.63 < 2.0 < 1.0 < 2.0 21.9 (V) 26.1

2 -- 26 -- -- -- -- -- -- 13.8 -- -- -- -- -- -- 58 (V) --

0.5 0.983 J 16.9 154 0.79 1.35 32.1 8.51 20.5 36.8 0.0833 3.09 23.5 1.75 J < 1.0 < 2.0 50.2 (V) 96.5

2 -- 23.6 -- -- -- -- -- -- 31.2 -- -- -- -- -- -- 51.1 (V) --

0.5 < 2.0 24.8 175 0.747 1.41 31.9 8.26 22.5 68.2 0.147 2.53 20.1 2.19 J < 1.0 < 2.0 46.8 (V) 151

2 -- 2.38 (A) -- -- -- -- -- -- 9.06 -- -- -- -- -- -- 39.8 (V) --

0.5 < 2.0 10.4 (A) 135 0.702 1.25 30.4 6.70 18.7 18.6 0.212 1.96 21 1.34 J < 1.0 < 2.0 47.6 (V) 80.6

2 -- 8.68 (A) -- -- -- -- -- -- 11.6 -- -- -- -- -- -- 28 (V) --

0.5 0.881 J 25.2 134 0.371 0.647 15.2 8.67 8.42 21.3 0.101 1.31 7.16 < 2.0 < 1.0 < 2.0 37.4 (V) 79.0

2 -- <0.46^ -- -- -- -- -- -- 1.68 -- -- -- -- -- -- 14.4 (V) --

11 / 160 (50)

0.067 / 0.31 15,000 / 220,000

(3,000) 16 / 230

(27) 78 / 1,100

(51) Not

Established 23 / 350

(28) 3,100 / 47,000

(14,000) 80 / 320

(160) 13 / 190

(44) 390 / 5,800

(1,800) 820 / 11,000

(86) 390 / 5,800

(1,700) 390 / 5,800

(1,800)

0.78 / 12

(3.5) 390 / 5,800

(470) 23,000 / 350,000

110,000)

11 (HH) 0.067 (HH) 390 (ECO) 5 (ECO) 1.9 (ECO) 160 (ECO) 23 (HH) 180 (ECO) 32 (ECO) 13 (HH) 6.9 (ECO) 86 (HH) 2.4 (ECO) 25 (ECO) 0.78 (HH) 18 (ECO) 340 (ECO)

31 / 470 0.11 / 0.36 15,000 / 220,000 15 / 210 5.2 / 7.3 36,000 / 170,000 23 / 350 3,100 / 47,000 80 / 320 1.0 / 4.4 390 / 5,800 490 / 3,100 390 / 5,800 390 / 1,500 0.78 / 12 390 / 1,000 23,000 / 350,000 DTSC-Modified Screening Levels (2)

(for human health risk) Residential or Commercial Land Use

" Tier 1 ESL " (all possible pathways & land uses) Basis = Human Health (HH), Leachability (L), Ecologic (Eco), or Odor (O)

Environmental Screening Levels (ESLs) (1)

Human Health & Safety Pathways (including groundwater)

Residential or Commercial Land Use (constuction worker)

(see notes on next page)

Table 2

Summary of Soil Analytical Results

Metals Analysis (CAM 17) 125 Coral Street, Santa Cruz

All soil results are in milligrams per Kilogram (mg/Kg)

Sample Information CAM-17 Metals by EPA Method 6010B

SS-1

SS-2

SS-3

SS-4

SS-5

11/25/2019

11/25/2019

11/25/2019

11/25/2019

11/25/2019

(ft)

Antimony Arsenic (A) Barium Beryllium Cadmium Chromium Cobalt Copper Lead Mercury Molybdenum Nickel Selenium Silver Thallium Vanadium (V) Zinc

Table 2

Summary of Soil Analytical Results

Metals Analysis (CAM 17) 125 Coral Street, Santa Cruz

All soil results are in milligrams per Kilogram (mg/Kg)

Sample Information CAM‐17 Metals by EPA Method 6010B

Notes:

BOLD = A laboratory result was detected (i.e., detected above the Reported Detection Limit (RDL)).

BOLD = Lab result was detected at or above the ESL or DTSC Residential Land Use Threshold.

BOLD = Lab result was detected at or above the ESL or DTSC Commercial Land Use or Construction Worker Threshold.

BOLD = Lab result was detected at a concentration that is at or above the most conservative Tier 1 threshold

BOLD = Lab result was detected above the Commercial Land Use ESL but below the Naturally Occuring (background) Concentration

1 = ND =

NE =

TIER 1 ESL = J =

L =

HH =

ECO =

O =

A =

V =

2 = ^ =

RDL =

Laboratory reports that the detection value is between MDL and RDL, and should be considered an estimate.The most conservative Environmental Screening Level (ESL) across all potential pathways including leaching, human health, ecolologic ("Terrestrial Habitat"), volatilization (inhalation).

Environmental Screening Levels (ESLs): Regional Water Quality Control Board (San Francisco Bay Region) guideline document: Screening for Environmental Concerns at Sites With Contaminated Soil and Groundwater (Final version, 2019). The ESLs are intended to provide quantitative risk‐based guidance on whether further assessment or remediation of contamination is warranted <https://www.waterboards.ca.gov/sanfranciscobay/water_issues/programs/ESL/new/ESL_Summary_Tables_24Jan19_Rev1.pdf >

Reported Detection Limit = is the laboratory‐determined value that is 2 to 5 times above the Method Detection Limit (MDL) that can be reproduced in a manner that results in a 99% confidence level and is both accurate and precise.

US EPA Region 9 Soil Regional Screening Levels (RSLs): From US EPA Regional Screening Levels for Soil ( https://www.epa.gov/risk/regional‐ screening‐levels‐rsls‐generic‐tables ) , last updated November‐2019 using the Summary Table [based on Carcinogenic Target Risk (TR) =1E‐6, Noncancer Hazard Index (HI) =1.0].

Method Detection Limit is used due to Reported Detection Limit greater than established threshold.

A "less than" symbol indicates no detectable concentrations (i.e., the laboratory did not detect the contaminant at the concentration shown).

CA DTSC Soil Screening Levels: From the California Department of Toxic Substances Control (DTSC), Office of Human and Ecological Risk (HERO), Human Health Risk Assessment (HHRA) Note Number 3, Table 1, April 2019. If no DTSC screening level is established then the corrisponding US EPA RSL is provided.

Indicates the lowest ESL is based on a potential Leaching pathway (for groundwater protection).

Indicates the lowest ESL is based on a potential Human Health & Safety Pathway (ingestion, inhalation, dermal).

Indcates the lowest ESL is based on a potential Terrestrial Habitat pathway.

Indicates the lowest ESL is based on a potential "odor nuisance" (i.e. 100 mg/kg for gasoline).

Not Detected at the laboratory's detection limit.

Not Established Not Analyzed

Arsenic: Multiple studies in the Santa Cruz County region show that naturally‐occurring Arsenic concentrations typically fall within range of 4‐ to‐12 mg/kg .

Vanadium: There is no local study that has established the naturally‐occurring Vanadium concentrations in the Santa Cruz County region.

However, the average Vanadium concentration in a study of Califorina soils was calculated to be 112 mg/kg (Source: Background Concentrations of Trace and Major Elements in California Soils , Kearny Foundation 1993).

(inches below ground surface)

SV- 1 5 <5 Acetone = 55 133.33 160 0.05

SV- 2 5 <5

Acetone = 52

1-Ethyl-4-methylbenzene = 9.4

1,2,4-Trimethylbenzene = 13

83.75 170 0.08

SV- 3 5 <5 Acetone = 110 133.33 130 0.04

5 Various --

20,000 83,000 3.2 14 37 160 10,000 44,000 3,500 15,000 2.8 12 15 67 Acetone = 1,100,000 / 4,500,000

1-Ethyl-4-methylbenzene = NE

1,2,4-Trimethylbenzene = NE

12 53 37 163 173,333 733,333 3,333 14,667 2.8 12 367 1,567 --

3.2 14 37 163 10,333 43,333 3,333 14,666 2.8 12 15.3 67 Acetone = 1,100,000 / 4,500,000

1-Ethyl-4-methylbenzene = NE

1,2,4-Trimethylbenzene = NE

Notes 1 =

2 =

PCE = Tetrachloroethene -- = Sample was not analyzed for this constituent BOLD = Compound detected.

< X = Constituent not detected above laboratory's Method Detection Limit (MDL), X. J = Laboratory note: Estimated value between the laboratory method detection limit and PQL

BOLD = Analytical result exceeds Commercial US EPA RSL, CA DTSC or ESL threshold. ^ = Laboratory Method Detection Limit (MDL) was used due to the PQL being higher than an established screening level

BOLD = Analytical result exceeds Residential US EPA RSL, CA DTSC or ESL threshold.

CA DTSC Modified Air Screening Levels: From the California Department of Toxic Substances Control (DTSC), Office of Human and Ecological Risk (HERO), Human Health Risk Assessment (HHRA) Note Number 3, Table 3, April 2019. < https://www.dtsc.ca.gov/AssessingRisk/upload/HHRA-Note-3-June-2018.pdf >

US EPA Region 9's Regional Screening Levels (RSLs): From US EPA Regional Screening Levels for Indoor Air (https://www.epa.gov/risk/regional-screening-levels-rsls-generic-tables) .

The Indoor Air RSLs are divided by the US EPA's Recommended Vapor Attenuation Factor (0.03) (from the US EPA’s Recommended Vapor Attenuation Factor for Risk Based Screening of sub-slab soil gas [Table 6-1 in Final Guidance for Assessing and Mitigating the Vapor Intrusion Pathway From Subsurface

Sources to Indoor Air , May 2019]) to calculate the Risk Level concentration appropriate for the specific sample collected (i.e., Sub-slab soil gas , "Near-source" exterior soil gas , Crawl space air , etc.).

N o ve m b e r

, 2

California DTSC-Modified Soil Gas Levels( 2)

Residential / Commercial Land Use

(ATTENUATION FACTOR: 0.03)

Not

Established

Environmental Screening Levels (ESLs): from User's Guide: Screening for Environmental Concerns at Sites With Contaminated Soil and Groundwater, set by the San Francisco Bay Regional Water Quality Control Board (Interim Final, Jan 2019)

<https://www.waterboards.ca.gov/sanfranciscobay/water_issues/programs/ESL/ESLs.html >. The ESLs are intended to provide quantitative risk-based guidance on whether further assessment or remediation of contamination is warranted. The ESLs used in this table were obtained from the above referenced document,"Tier 1 ESLs", based on shallow soils (<3m), groundwater is a current or potential source of drinking water.

8.4 <10

8.9 J 7901006,900

Table 3:

< 200 11 J

Napthalene

110 J

Xylenes

Summary of Soil Vapor - Volatile Organic Compounds Analytical Results

125 Coral Street, Santa Cruz

All soil vapor results are in micrograms per meter cubed (ug/m 3 )

Leak Check Monitoring

(Isopropyl Alcohol)

Laboratory

Results

(in ug/m3)

Calculated

Leakage

(percent)

Other VOCs

Field Shroud

Concentration

(avg., in ppm)

<40

--2.0 --5.0 10

Toluene Total Petroleum Hydrocarbons as Gasoline

Volatile Organic Compounds (VOCs)

Laboratory Analysis by EPA Method TO-15

PCEEthylbenzene

< 200 <2.0 <5.0

Sample Information

Benzene

<42

<43

US EPA Regional Screening Levels

Residential / Commercial

(0.03 ATTENUATION FACTOR) (2)

Not Established

Environmental Screening Levels (1)

Residential / Commercial

(0.03 ATTENUATION FACTOR)

Laboratory's Practical Quantitation Limit (PQL)

23 J

200 2.0

1 Weber, Hayes and Associates

Pat Hoban Highlight

Sample

ID

Depth (ft BGS)

Arsenic

(mg/kg)

Sample

ID

Depth (ft BGS)

Arsenic

(mg/kg)

SS-1 0.5 82.5 SS-5 2 0.46

SS-1 2 26 9 9 SS-3 2 2.38

SS-2 0.5 16.9 0 SS-4 2 8.68

SS-2 2 23.6 0.46 15.38 4 SS-4 0.5 10.4

SS-3 0.5 24.8 26 16.9 5 SS-2 0.5 16.9

SS-3 2 2.38 10.18 1.376 6 SS-2 2 23.6

SS-4 0.5 10.4 0.662 -0.366 7 SS-3 0.5 24.8

SS-4 2 8.68 8 SS-5 0.5 25.2

SS-5 0.5 25.2 9 SS-1 2 26

SS-5 2 <0.46 10 SS-1 0.5 82.5 (Removed)

0.871

0.829

0.235

0.295

21.69 20.52

21.62

21.69

95% Modified-t UCL (Johnson-1978)

Suggested UCL to Use

95% Student's-t UCL

Assuming Normal Distribution

95% Normal UCL 95% UCLs (Adjusted for Skewness)

95% Student's-t UCL 95% Adjusted-CLT UCL (Chen-1995)

SD SD of logged Data

Coefficient of Variation Skewness

Number of Missing Observations

Minimum Mean

Maximum Median

Chebyshev UCL can be computed using the Nonparametric and All UCL Options of ProUCL 5.0

Note: Sample size is small (e.g., <10), if data are collected using ISM approach, you should use guidance provided in ITRC Tech Reg Guide on ISM (ITRC, 2012) to compute statistics of interest.

For example, you may want to use Chebyshev UCL to estimate EPC (ITRC, 2012).

Normal GOF Test

Lilliefors Test Statistic Lilliefors GOF Test

5% Lilliefors Critical Value Data appear Normal at 5% Significance Level

Shapiro Wilk Test Statistic

5% Shapiro Wilk Critical Value

Shapiro Wilk GOF Test

Data appear Normal at 5% Significance Level

Data appear Normal at 5% Significance Level

Data Set

Sorted Data Set

(sorted by concentration)

Calculation Sheet 1

Arsenic Levels at 0.5 to 2 Feet

ProUCL Statistics

125 Coral Street, Santa Cruz

Total Number of Observations Number of Distinct Observations

General Statistics

Note: Suggestions regarding the selection of a 95% UCL are provided to help the user to select the most appropriate 95% UCL.

These recommendations are based upon the results of the simulation studies summarized in Singh, Singh, and Iaci (2002) and Singh and Singh (2003). However, simulations results will not cover all Real World data sets.

For additional insight the user may want to consult a statistician.

0.0

5.0

10.0

15.0

20.0

25.0

30.0

0 1 2 3 4 5 6 7 8 9 10

A rs e n ic C o n ce n tr at io n s m g/ kg

9 Discrete Shallow Soil Samples

Arsenic Concentrations (Complete 9 Soil Samples Set)

Arsenic Concentrations Linear (Arsenic Concentrations)

Weber, Hayes and Associates

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Highlight

Sample

ID

Depth (ft BGS)

Vanadium

(mg/kg)

Sample

ID

Depth (ft BGS)

Vanadium

(mg/kg)

SS-1 0.5 21.9 1 SS-5 2 14.4

SS-1 2 58 10 10 2 SS-1 0.5 21.9

SS-2 0.5 50.2 0 3 SS-4 2 28

SS-2 2 51.1 14.4 39.52 4 SS-5 0.5 37.4

SS-3 0.5 46.8 58 43.3 5 SS-3 2 39.8

SS-3 2 39.8 14.09 0.443 6 SS-3 0.5 46.8

SS-4 0.5 47.6 0.357 -0.639 7 SS-4 0.5 47.6

SS-4 2 28 8 SS-2 0.5 50.2

SS-5 0.5 37.4 9 SS-2 2 51.1

SS-5 2 14.4 0.937 10 SS-1 2 58

0.842

0.197

0.28

47.69 45.89

47.54

47.69

For additional insight the user may want to consult a statistician.

Normal GOF Test

5% Lilliefors Critical Value Data appear Normal at 5% Significance Level

These recommendations are based upon the results of the simulation studies summarized in Singh, Singh, and Iaci (2002) and Singh and Singh (2003). However, simulations results will not cover all Real World data sets.

Note: Suggestions regarding the selection of a 95% UCL are provided to help the user to select the most appropriate 95% UCL.

95% Student's-t UCL

Calculation Sheet 2

Vanadium Levels at 0.5 to 2 Feet

ProUCL Statistics

125 Coral Street, Santa Cruz

Minimum Mean

Suggested UCL to Use

Data appear Normal at 5% Significance Level

Data appear Normal at 5% Significance Level

Data Set

Sorted Data Set

(sorted by concentration)

Total Number of Observations Number of Distinct Observations

Number of Missing Observations

Maximum Median

Shapiro Wilk Test Statistic Shapiro Wilk GOF Test

5% Shapiro Wilk Critical Value

95% Student's-t UCL 95% Adjusted-CLT UCL (Chen-1995)

95% Modified-t UCL (Johnson-1978)

Lilliefors Test Statistic Lilliefors GOF Test

Assuming Normal Distribution

95% Normal UCL 95% UCLs (Adjusted for Skewness)

General Statistics

SD SD of logged Data

Coefficient of Variation Skewness

0 1 2 3 4 5 6 7 8 9 10

V an ad iu m C o n ce n tr at io n s m g/ kg

10 Discrete Shallow Soil Samples

Vanadium Concentrations (Complete 10 Soil Samples Set)

Vanadium Concentrations Linear (Vanadium Concentrations)

Weber, Hayes and Associates

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