SOIL AND GROUNDWATER MANAGEMENT PLAN ADDENDUM COOLEY LANDING 2100 BAY ROAD EAST PALO ALTO, CALIFORNIA

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1 SOIL AND GROUNDWATER MANAGEMENT PLAN ADDENDUM COOLEY LANDING 2100 BAY ROAD EAST PALO ALTO, CALIFORNIA PREPARED FOR: Ms. Sharon Jones City of East Palo Alto 1960 Tate Street East Palo Alto, California PREPARED BY: Ninyo & Moore Geotechnical and Environmental Sciences Consultants 1956 Webster Street, Suite 400 Oakland, California July 12, 2013 Project No

2 July 12, 2013 Project No Ms. Sharon Jones City of East Palo Alto 1960 Tate Street East Palo Alto, California Subject: Soil and Groundwater Management Plan Addendum Cooley Landing 2100 Bay Road East Palo Alto, California Dear Ms. Jones: Ninyo & Moore is pleased to submit this Soil and Groundwater Management Plan (SGMP) Addendum prepared for the Cooley Landing located at 2100 Bay Road in East Palo Alto and Menlo Park, California (site). This SGMP Addendum was prepared at the request of the City of East Palo Alto and in general accordance with our proposal dated May 23, 2013, and discussions with staff at the San Francisco Bay Regional Water Quality Control Board (RWQCB). This SGMP Addendum has been prepared to address the incorporation of a section of Bay Road known as the Cooley Landing Access Road into the project site boundary for Cooley Landing. This SGMP Addendum is intended to supplement the SGMP previously prepared for the Cooley Landing by Ninyo & Moore, dated January 16, We appreciate the opportunity to be of service to the City of East Palo Alto on this project. Sincerely, NINYO & MOORE Cem R. Atabek Senior Project Environmental Engineer CRA/KML/csj Kris M. Larson, P.G Principal Environmental Geologist Distribution: (1) Addressee (1) Mark Johnson, RWQCB (1) Greg Schirle, San Mateo County Department of Environmental Heath (1) Frank Davies, CalRecycle

3 TABLE OF CONTENTS Page 1. INTRODUCTION PURPOSE SITE CONCEPTUAL MODEL Site Location and Description Remedial Action Plan Implementation Planned Site Improvements Hazard Summary of Constituent of Potential Concern (COPCs) Metals PCBs OCPs PAHs Subsurface Conditions at Cooley Landing Access Road PROJECT DESCRIPTION REFERENCES...10 Figures Figure 1 Site Location Figure 2 Cooley Landing Site Map R - SGMP Addendum.doc i

4 1. INTRODUCTION This Soil and Groundwater Management Plan (SGMP) Addendum has been prepared for the City of East Palo Alto for Cooley Landing located at 2100 Bay Road, East Palo Alto and Menlo Park, California (site). This SGMP Addendum was prepared at the request of the City of East Palo Alto and in general accordance with our proposal dated May 23, 2013, and discussions with staff at the San Francisco Bay Regional Water Quality Control Board (RWQCB). This SGMP Addendum has been prepared to address the incorporation of a section of Bay Road known as Cooley Landing Access Road into the project site boundary for Cooley Landing as part of Phase 2 of the Cooley Landing project. This SGMP Addendum supplements the Revised SGMP previously prepared for Cooley Landing by Ninyo & Moore, dated January 16, Contaminants of Potential Concern (COPCs) have been detected in cover fill soils and in burned wastes on site. Elevated concentrations of these COPCs are present in shallow subsurface materials at concentrations that pose potential hazards to site users, construction workers, and the aquatic habitat of San Francisco Bay. As a result of these environmental conditions, remedial action consisting of the construction of engineered caps was performed at the site prior to it s redevelopment as a public park. Additional remedial actions (construction of engineered caps) have been proposed to be implemented during Phase 2 of the Cooley Landing Park Project which will consist primarily of utility trench installation and improvements to Cooley Landing Access Road and site parking areas. The proposed additional remedial actions are discussed in the RAP Addendum prepared by Ninyo & Moore dated July 12, 2013, and Operations and Maintenance (O&M) Plan Addendum prepared by Ninyo & Moore dated July 12, The Revised SGMP was prepared to summarize the protocol to be implemented during planned construction of the site into a public park. The Revised SGMP and this SGMP Addendum should be implemented during construction activities including, but not limited to, subsurface utility installations, implementing the planned remedial action consisting of constructing engineered caps, and other activities associated with the development of the site. The Revised SGMP and this SGMP Addendum should be implemented in conjunction with O&M Plan, dated July 13, 2012, and O&M Plan Addendum, dated July 12, 2013, when a future activity subsequent to remedial action and park development involves potentially disturbing the engineered cap. The O&M Plan R - SGMP Addendum.doc 1

5 and O&M Plan Addendum were prepared by Ninyo & Moore under separate covers will be implemented following completion of the remedial action activities. The O&M Plan and O&M Plan Addendum present the policies and procedures to be implemented for long-term operation, maintenance, monitoring, and inspection related to the Cooley Landing site. 2. PURPOSE This SGMP Addendum serves primarily to incorporate the area of Cooley Landing Access Road into the project site boundaries so that the guidelines of the Revised SGMP will be followed during work performed within the Cooley Landing Access Road area. The Revised SGMP addresses worker health and safety controls, personnel assignments and responsibilities, cover fill soils/waste excavation, management of contaminated and potentially contaminated materials, onsite reuse and, if required, off-site disposal procedures, stockpile management, and provides recommendations to reduce exposure to workers and the public from contaminants, if encountered. Work performed under the Revised SGMP and SGMP Addendum shall be in compliance with the project specifications for cap construction, a site health and safety plan, and applicable local, state, and federal statutes and regulations. 3. SITE CONCEPTUAL MODEL 3.1. Site Location and Description The site includes an approximately 8.5 acre peninsula with a physical address of 2100 Bay Road in East Palo Alto, California, and an approximately 800-foot long section of Bay Road (known as Cooley Landing Access Road) between the automobile salvage facility located at 2091 Bay Road and the parking lot at the western edge of Cooley Landing (Figure 1). The site is currently owned by the City and District and is assigned Assessor s Parcel Number (City), and and (District). The project site boundaries along Cooley Landing Access Road extend from the northern edge of the asphalt-paved pedestrian trail on the north side of the vehicular roadway, to the southern edge R - SGMP Addendum.doc 2

6 of the vehicular roadway. The site extends into San Francisco Bay and is geographically located at the eastern extent of Bay Road. A gravel-paved access road traverses the site generally southwest to northeast and is a continuation of Bay Road. The City and District has redeveloped the Cooley Landing peninsula into a public park. The park is currently open to the public and includes: bike and walking trails; a bike rack/parking area adjacent to the Boat Works building (which is fenced off to restrict public access to the building); viewing and interpretive areas; several areas for wildlife viewing and interpretation; a wetlands area; and parking areas. Surface elevations range from zero to approximately 14 feet above mean sea level (msl). The peninsula occupies a portion of the Ravenswood Open Space Preserve (ROSP) that also includes a former salt pond, which extends to the north. The peninsula is bordered to the north, east, and south by the San Francisco Bay, and to the west by Cooley Landing Access Road, the ROSP and the Palo Alto Baylands Nature Preserve. Cooley Landing Access Road is bordered by the Baylands Nature Preserve to the south, the ROSP to the north, an industrial area and Bay Road to the west, and by the peninsula to the east (Figure 2) December 2011 Remedial Action Plan Implementation Remedial actions were implemented at the Cooley Landing peninsula in December 2011 following the guidelines presented in the Remedial Action Plan (RAP) prepared by Ninyo & Moore, dated December 20, 2010 (N&M 2010). The implementation of the RAP is documented in the Remedial Action Completion Report prepared by Ninyo & Moore, dated April 16, 2012 (N&M 2012). Remedial actions included installation of an engineered cap over the entire surface of the Cooley Landing peninsula. The engineered cap was constructed of imported clean soil, geosynthetic liners, and hardscape materials including gravel, aggregate base (AB), decomposed granite, cobbles, asphalt, and concrete. The engineered cap generally consisted of 2 feet of clean imported soil; however, the engineered cap within hardscaped areas was generally thinner. The area surrounding the western parking lot onsite, known as the District Extension Area, was incorporated into the project site boundaries after completion of RAP implementation activities for the remainder of the Cooley Landing R - SGMP Addendum.doc 3

7 peninsula. The engineered cap installed within the District Extension Area surrounding the western parking lot was comprised of 6 inches of crushed concrete overlain with 1 foot of imported clean soil. Following remedial activities an SGMP as well as an O&M Plan were implemented at the Cooley Landing peninsula Planned Site Improvements Utility trenching and roadwork activities are planned for Cooley Landing Access Road and site parking areas as part of the 2 nd phase of park development activities. The planned utility trenching activities include installation of water, sanitary sewer, and electrical/communications lines in three separate trenches within the roadway to provide services to the future park. The planned roadwork activities include asphalt paving of the roadway and parking areas, installation of concrete curbs and pavements, and the replacement of soil and installation of light poles and a perforated drainage pipe within the planting strip along the north side of the roadway. Rehabilitation of the asphalt-paved pedestrian trail to the immediate north of the roadway and planting strip is also planned as part of the construction activities. Rehabilitation of the pedestrian trail will involve patching cracks in the exist asphalt, grinding the existing asphalt, and installing a new finish (sealing) coat of asphalt. The 3 rd phase of planned park development activities includes demolishing the existing Boat Works building and construction of a new Education Center building in its location. This 3 rd phase of park development activities will be implemented after the completion of improvements to Cooley Landing Access Road and site parking areas as discussed above Hazard Summary of Constituent of Potential Concern (COPCs) The media of concern for the site are the cover fill soils and burned waste beneath the engineered cap containing COPCs. The COPCs detected within the Cooley Landing peninsula portion of the site during previous investigations are described in the Revised SGMP. In April 2013, Ninyo & Moore performed soil sampling to evaluate potential impacts from fill material used to construct Cooley Landing Access Road as documented in Ninyo & Moore s Revised Soil Sampling Report, Cooley Landing Access Road, dated June 20, The R - SGMP Addendum.doc 4

8 COPCs detected within the Cooley Landing Access Road portion of the site were metals including arsenic, lead, and thallium; polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs). Soil sample analytical results were compared to the San Francisco Bay RWQCB Shallow Soil Environmental Screening Levels (ESLs) for commercial/industrial worker exposure scenario (Table K-2 ESLs; RWQCB, May 2013) and the RWQCB ESLs for construction/trench worker exposure scenario (Table K-3 ESLs; RWQCB, May 2013). Based on the results of the soil sampling and subsequent laboratory analysis, Ninyo & Moore presents the following findings and conclusions: Detected concentrations of OCPs were below ESLs. The PCB aroclor 1260 was detected at concentrations above Table K-2 ESLs and below Table K-3 ESLs in surface samples (0 to 1 foot bgs) from the eastern portion of the access road, and in one subsurface sample (1 to 2 feet bgs) from the western portion of the access road. Detected concentrations or the method detection limits (MDLs) of the following PAHs exceeded the Table K-2 ESLs and were below Table K-3 ESLs in one or more samples; benzo(a)anthracene, benenzo(a)pyrene (B[a]P), benzo(b)fluoranthene, and dibenz(a,h)anthracene. Arsenic was detected above the Table K-3 ESL in subsurface samples (1 to 2 feet bgs) in the eastern portion of the access road, and was detected above the Table K-2 ESL but below the Table K-3 ESL in all other samples. Lead was detected above the Table K-3 ESL in subsurface samples (1 to 2 feet bgs) in the central and eastern portion of the access road, and was detected below ESLs in all other samples. Thallium was detected above the Table K-3 ESL in one subsurface sample (1 to 2 feet bgs) in the east-central portion of the access road and was not detected in all other samples. Concentrations of metals in soil were generally higher in the central and eastern portion of the access road than in the western portion of the access road, and were generally higher in the subsurface samples than in the surface samples. The elevated concentrations of lead detected in the central and eastern portion of the access road suggest that soil in this area (particularly between 1 and 2 feet bgs) would likely be classified as hazardous waste, while the concentrations of lead and other COCs detected in the western portion of the access road suggest that soil in that area would likely be classified as non-hazardous waste R - SGMP Addendum.doc 5

9 The potential exposure routes relating to COPC-impacted fill soils beneath the engineered cap include inhalation of dust, soil ingestion, and dermal contact with soil and airborne particulates. In the case of the Cooley Landing site (which includes the peninsula and the access road), the distribution of COPCs in the cover fill soils beneath the engineered cap is inconsistent because the cover fill soils were imported from unknown off site source(s). A review of the analytical data for the cover fill soils indicates that the extent of COPC-impacted cover fill soils corresponds to the lateral extent of the imported cover fill soils or essentially the entire site, the current main source of concern to human and ecological health risk. Inhalation of COPC-impacted cover fill soils was considered a complete exposure pathway potentially creating adverse health risk conditions on site. Absorption of harmful chemicals through the skin or eyes is considered a significant exposure pathway for maintenance workers if COPC-impacted cover fill soils are encountered. Site visitors and potential occupants may also be exposed to the health risks if exposed to COPC-impacted cover fill soils through direct contact. Therefore, there is potential for dermal contact exposure for all human populations visiting, working or occupying the site, and the health risk related to dermal contact of site contaminants is a complete exposure pathway. Although the Cooley Landing peninsula was historically used as a former waste burn site, Cooley Landing Access Road is not known or suspected to be impacted with burn waste, only COPCs-impacted fill soils. Below is a detailed discussion of the COPCs detected within the Cooley Landing Access Road portion of the site which would remain beneath the engineered cap, and the health risks associated with each of the COPCs Metals Metals including arsenic, lead, and thallium were detected at concentrations exceeding ESLs in fill soils. A description of metals exceeding ESLs is provided in this section R - SGMP Addendum.doc 6

10 Arsenic is a toxic heavy metal. Some arsenic compounds may release a toxic gas when in an acidic environment. Inorganic arsenic is regulated by Occupational Safety and Health Administration (OSHA) as a carcinogen. Although arsenic is a known carcinogen, naturally occurring arsenic in San Francisco Bay Area soils is commonly encountered at concentrations which exceed ESLs by up to two orders of magnitude. Lead is a toxic heavy metal and a suspected carcinogen that may be encountered in inorganic or organic forms. Where lead is identified as present in sufficiently high concentrations, work will be conducted in accordance with the applicable OSHA standards. Thallium is a toxic heavy metal and a suspected carcinogen. Contact with skin is dangerous. Man-made sources of thallium pollution include gaseous emission of cement factories, coal burning power plants, and metal sewers. Other Heavy Metals may be present in fill soils at elevated concentrations. Some heavy metals are highly toxic; others are also recognized human carcinogens. Because metals are not volatile unless heated to high temperatures or exposed to other chemicals, control by proper use of PPE and personnel hygiene practices will help prevent significant exposure to heavy metals PCBs The PCB aroclor 1260 was detected in fill soils at concentrations exceeding ESLs. PCBs are recognized environmental pollutants and suspected human carcinogens OCPs OCPs including chlordane, alpha-chlordane, gamma-chlordane, 4,4 -DDE, 4,4 -DDT and dieldren were detected in fill soils, however the detected concentrations were below ESLs. In general, pesticides range from relativity low-toxicity products to highly poi R - SGMP Addendum.doc 7

11 sonous compounds. Exposure to extremely small quantities of some pesticides may result in serious bodily harm, even death. Identification of pesticide containers during future field activity requires evaluation by the Health and Safety Officer (SHSO) before work can proceed. Pesticides historically disposed at a site require that protective clothing protocols be implemented during all intrusive activity PAHs PAHs are the most widespread contaminant detected in the subsurface cover fill soils occurring throughout the site at concentrations exceeding their respective residential and commercial ESLs. PAHs are a recognized human carcinogen. Exposure by any route to PAHs and other recognized human carcinogens will be controlled by measures discussed later in this Plan Subsurface Conditions at Cooley Landing Access Road The area of Cooley Landing Access Road is constructed with the fill from undocumented sources. The surface of the roadway is assumed to be covered by approximately 6 to 12 inches of AB material. During Ninyo & Moore s April 2012 soil sampling activities, the surface layer of AB material was observed to be approximately 6 inches thick along the northern edge of the roadway, and the AB material is assumed to be thicker (approximately 8 to 12 inches thick) throughout the majority of the roadway. COPCs-impacted fill soil was encountered beneath the AB material to the deepest depth explored of approximately 2 feet bgs. It is assumed that similar COPCs impacted fill soils are present throughout the Cooley Landing Access Road area which includes the planting strip and asphalt paved pedestrian trail. Subsurface conditions below 2 feet bgs within the Cooley Landing Access Road area are unknown; however, Cooley Landing Access Road is not known or suspected to be impacted with burn waste R - SGMP Addendum.doc 8

12 4. PROJECT DESCRIPTION The recommended remedial alternative for Cooley Landing Access Road is construction of an engineered cap, including on-site reconsolidation and capping of COPCs-impacted materials excavated during roadwork and utility trenching activities, and potential off-site disposal of excess materials excavated during roadwork and utility trenching activities. Reconsolidation of the COPCs-impacted excavated materials would be performed in the area of the parking lot near the west end of the peninsula and within the footprint of a future Education Center building to be constructed near the eastern end of the peninsula in the location of the existing Boat Works building. Implementation of remedial action for Cooley Landing Access Road, including details on the proposed construction activities and engineered caps, are discussed in further detail in the RAP Addendum, dated July 12, 2013, and the O&M Plan Addendum, dated July 12, 2013 (Ninyo & Moore, 2013). The guidelines of the Revised SGMP will be followed during work performed within the Cooley Landing Access Road area R - SGMP Addendum.doc 9

13 5. REFERENCES Arcadis, Third and Fourth Quarter 2008 Semiannual Report, Former Romic Environmental Technologies Corporation, 2081 Bay Road, East Palo Alto, California: dated February 17. Callender and Associates 2010 Final Concept Plan and 2011 Remediation Extension Figures. Kleinfelder West, 2006a Phase I Environmental Site Assessment, Cooley landing Project, dated October 19. Kleinfelder West, 2006b Preliminary Geotechnical Feasibility Study for Cooley Landing Site in East Palo Alto, California, dated November 15. Kleinfelder West, Inc., 2010 Preliminary Biological Habitat Assessment, Wetlands Assessment Map, Figure 3 (revised ): dated January 12. Ninyo & Moore, 2010 Remedial Action Plan, Cooley Landing, 2100 Bay Road, East Palo Alto, California, dated December 20. Ninyo & Moore, 2012 Operations & Maintenance Plan, Cooley Landing, 2100 Bay Road, East Palo Alto, California, dated July 13. Ninyo & Moore, 2013, Revised Soil Sampling Report, Cooley Landing Access Road, Bay Road, East Palo Alto, California, dated June 20. Ninyo & Moore, 2013 Operations & Maintenance Plan Addendum, Cooley Landing, 2100 Bay Road, East Palo Alto, California, dated July 12. Ninyo & Moore, 2013, Remedial Action Plan Addendum, Cooley Landing, 2100 Bay Road, East Palo Alto, California: dated July 12. Ninyo & Moore, 2012, Revised Soil and Groundwater Management Plan, Cooley Landing, 2100 Bay Road, East Palo Alto, California: dated January 16. San Francisco Bay (Region 2), 2007 Water Quality Control Plan (Basin Plan), dated January R - SGMP Addendum.doc 10

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