SITE INVESTIGATION REPORTCalifornia Department ….doc

PREPARED FOR: CALIFORNIA DEPARTMENT OF TRANSPORTATION DISTRICT 4 OFFICE OF ENVIRONMENTAL ENGINEERING, HAZARDOUS WASTE BRANCH 111 W. GRAND AVE OAKLAND, CALIFORNIA PREPARED BY: SHAW ENVIRONMENTAL, INC. 1326 NORTH MARKET BOULEVARD SACRAMENTO, CALIFORNIA CONTRACT 43A0078 TASK ORDER NO. 04-112371-CY Site Investigation Report Route 1 - Devils Slide Tunnel Project Pacifica - San Mateo County SITE INVESTIGATION REPORT AERIALLY DEPOSITED LEAD INVESTIGATION ROUTE 1 AT DEVILS SLIDE PACIFICA, SAN MATEO COUNTY, CALIFORNIA 四月 3, 2021 Prepared for: California Department of Transportation North Region Hazardous Waste Office District 4 111 Grand Avenue, 14th Floor Oakland, California 94623 Prepared by: Shaw Environmental, Inc. 1326 North Market Boulevard Sacramento, California 95834-1912 Task Order No.: 04-276701-CN Caltrans Contract No.: 43A0078 Project No.: 845013.0101 SITE INVESTIGATION REPORT AERIALLY DEPOSITED LEAD INVESTIGATION ROUTE 1 AT DEVILS SLIDE PACIFICA, SAN MATEO COUNTY, CALIFORNIA 四月 3, 2021 Prepared for: California Department of Transportation North Region Hazardous Waste Office District 4 111 Grand Avenue, 14th Floor Oakland, California 94623 Prepared by: Shaw Environmental 1326 North Market Boulevard Sacramento, California 95834-1912 Task Order No.: 04-112371-CY Caltrans Contract No.: 43A0078 Project No.: 845013.0101 _ Benjamin ChevlenMartha Adams, P.E. Staff GeologistProject Manager Report Limitations This report has been prepared in accordance with generally accepted practices using standards of care and diligence normally practiced by recognized consulting firms performing services of a similar nature. This report presents our professional judgment based upon data and findings identified in this report and the interpretation of such data based on our experience and background, and no warranty, either expressed or implied, is made. The conclusions presented are based on the current regulatory climate and may require revision if future regulatory changes occur. The findings identified in this report are predicated on the results of the limited sampling and laboratory testing performed. This report does not address impacts related to sources other than those specified herein. The contents of this report reflect the views of Shaw Environmental, Inc., who is responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the State of California or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. SHAW ENVIRONMENTAL, INC. Martha Adams, P.E. Project Manager CALIFORNIA DEPARTMENT OF TRANSPORTATION OFFICE OF ENVIRONMENTAL ENGINEERING - HAZARDOUS WASTE BRANCH Reviewed by: _ Naveen Aachi Task Order Manager Recommended by: _ Celia McCuaig, P.E. Senior Environmental Engineer Approved by: _ Allen Baradar, P.E., REA District Office Chief Project Team ContactAffiliationResponsibility Celia McCuaig, P.E. (510) 286-5659 Contract Manager Naveen Aachi (510) 286-4914 Department District 4 Office of Environmental Engineering, Hazardous Waste Branch 111 Grand Avenue, 14th Floor Oakland, California 94623 Task Order Manager Martha Adams, P.E. (916) 565-4183 Project Manager Benjamin Chevlen (916) 565-4353 Shaw Environmental, Inc. 1326 North Market Blvd Sacramento, California 95834 Site Supervisor Table of Contents _ List of Tables.v List of Figures.v List of Appendices.v Report Limitations.iii Project Team.iv Executive Summary.1 1.0Introduction.1-1 1.1Project Description.1-1 1.2Project Objective.1-1 2.0Scope of Work.2-1 2.1Planning and Permitting.2-1 3.0Field Investigation.3-1 3.1Laboratory Analyses.3-2 4.0Site Investigation Results.4-1 4.1Lead Investigation Results.4-1 5.0Data Evaluation.5-1 5.1Lead Concentrations and Distribution.5-1 5.2Lead Data Statistical Analysis.5-2 5.2.1Summary .5-4 6.0Conclusions and Recommendations.6-1 7.0References.7-1 List of Tables _ Table 1 Lead Analytical Data and GPS Locations List of Figures _ Figure 1 Site Location Map Figure 2 Boring Location Map List of Appendices_ Appendix A Drilling and Sampling Procedures Appendix B Laboratory Analytical Reports and Chain-of-Custody Forms Appendix C Lead Statistical Analysis Spreadsheets Executive Summary This report presents the results of the soil investigation that was conducted by Shaw Environmental, Inc. along State Route (SR) 1 in San Mateo County, California (Figure 1). The investigation as described in this report was conducted along the northbound and southbound shoulders of SR 1 between post mile (PM) 36.6 and 40.9 in San Mateo County, California (Figure 2). This investigation was conducted at the request and authorization of Mr. Naveen Aachi of the California Department of Transportation (Caltrans) and in general accordance with Caltrans Contract 43A0078, Task Order Number 04-112371-CY. The purpose of the investigation was to evaluate the presence and concentration of aerially deposited lead in soil prior to improvement activities proposed for SR 1. The objective was to screen soil that will be excavated from the site during the proposed construction activities. The site investigation included the advancement of 9 shallow soil borings along the northbound shoulder and 4 shallow soil borings along the southbound shoulder area of SR-1 using direct- push sampling equipment. Three soil samples per boring location were collected for analysis from depths of 0.0 to 0.30 meters (0.0 to 1.0 feet), 0.46 to 0.76 meters (1.5 to 2.5 feet), and 0.91 to 1.22 meters (3.0 to 4.0 feet) below ground surface, respectively. A total of 34 soil samples were collected and submitted for analysis. Lead was reported in soil samples collected from the site. Total lead concentrations ranged from less than 1.0 to 448 milligrams per kilogram (mg/kg) in soil samples analyzed. The source for the lead is not known, however, it is thought to be related to accumulation of dust and debris containing lead from leaded gasoline emissions. Lead concentrations were compared to Total Threshold Limit Concentration (TTLC) of 1,000 mg/kg, and Soluble Threshold Limit Concentration (STLC) of 5 milligrams per liter (mg/l) values to evaluate whether the soil would be considered a California hazardous waste, should it become a waste. No soil samples analyzed during this investigation exceeded the TTLC value of 1,000 mg/kg for total lead. Only one soil sample, collected in surface soil in boring 1, was reported to contain total lead in excess of 350 mg/kg, a level requiring waste disposal in a Class I facility. A total of two soil samples were reported to contain soluble lead at concentrations in excess of the STLC of 5 mg/l by Waste Extraction Test (WET) analysis. Soil samples reported to contain soluble lead exceeding the STLC would be considered a California hazardous waste, should the soil become a waste. Soil at specific sample points may be classified as a California hazardous waste, however, the data from all intervals were combined into one data set for analysis as Caltrans construction plans typically call for excavation of soil to 0.6 meters (2 feet) for road base preparation. A statistical analysis for the total lead data was conducted on the entire data set. The results of the soil investigation are summarized below. Area Soil Interval (m) Total Lead Mean (mg/kg) Total Lead 90% UCL (mg/kg) Predicted WET Lead Concentration (mg/l) SR 10.0 to 1.2232.5342.432.27 The mean concentration and 90% Upper Confidence Level values for total lead data were less than 350 mg/kg. This suggests that the soil, if treated as a whole and sampled on a composite basis from stockpiles generated during construction activities, may not require Class I disposal. The excavated soil would likely not require soluble lead analysis by the WET, as the mean was less than 50 mg/kg. Based on the statistical analysis conducted, the waste soil, if treated as a whole and sampled on a composite basis from stockpiles generated during construction activities, would not be considered a California hazardous waste. Special handling and disposal procedures may not be required, except as needed to protect worker health and safety. 1.0Introduction This report has been prepared by Shaw Environmental Inc. (Shaw) to present the results of the soil investigation that was conducted along State Route (SR) 1 in San Mateo County, California (Figure 1). The investigation as described in this report was conducted along the northbound and southbound shoulder areas of SR 1 south of Pacifica between PM 36.6 and 40.9 in San Mateo County, California. This investigation was conducted at the request and authorization of Mr. Naveen Aachi of the California Department of Transportation (Caltrans) and in general accordance with Caltrans Contract 43A0078, Task Order Number 04-112371-CY. 1.1Project Description Caltrans proposes to construct a double bore tunnel and bridge separating the two directions of traffic to bypass the geologically unstable area of Route 1 at Devils Slide in San Mateo County. All work for this site investigation was performed within Caltrans right-of-way. Shaw is not aware of any previous site investigative work in the project area. 1.2Project Objective The objective of this investigation was to determine the presence or absence of hazardous concentrations of aerially deposited lead (ADL) in shallow soil within the existing right-of-way of SR 1 in San Mateo County. The purpose of this site investigation was to screen soil that will be excavated from the site during the proposed construction activities. The results from the ADL investigation will be used to assess worker health and safety issues, soil handling and disposal procedures, and determine the applicability of the Department of Toxics Substance Control (DTSC) variance for re-use of lead contaminated soil. 2.0Scope of Work The scope of work for the investigation was presented in Shaws workplan dated June 11, 2003, which was approved for implementation by Caltrans. The following scope of work was conducted: 1.Planning 2.Field Investigation 3.Laboratory Analyses 4.Site Investigation Report Preparation 2.1Planning Planning included a pre-work site visit and preparation of a work plan and health and safety plan. Mrs. Martha Adams and Mr. Benjamin Chevlen of Shaw and Mr. Naveen Aachi and Mr. Abdullah Akram of Caltrans conducted a pre-work site meeting on June 9, 2003. Items discussed and reviewed during the meeting included the scope of work, the site visit checklist, and the project schedule. Mrs. Martha Adams and Mr. Benjamin Chevlen of Shaw performed a field reconnaissance of the project area and marked the boring locations for Underground Service Alert (USA). USA was notified of the subsurface investigation at least 48 hours prior to initiation of the investigation. A site-specific workplan (Shaw, 2003a) was prepared presenting the scope of work and the procedures implemented during the investigation. The workplan also provided information regarding laboratory analyses, investigation-derived waste, and report preparation. A site-specific health and safety plan (Shaw, 2003b) was prepared in general accordance with 29 CFR 1910.120. The health and safety plan included safety procedures for work performed at the site, chemical hazard information, site safety officers, and preferred medical emergency locations (Shaw, 2003b). 3.0Field Investigation The field investigation was conducted on June 13, 2003. The site investigation included the advancement of 9 shallow soil borings along the northbound shoulder and 4 shallow soil borings along the southbound shoulder area of SR 1 (Figure 2) to provide data for the systematic evaluation of subsurface soil conditions prior to the implementation of the proposed construction activities. The soil boring locations were selected according to Caltrans Task Order No. 04- 112371-CY. Work was conducted between the hours of 9:00 A.M. and 3:00 P.M., in the unpaved portion of the shoulder, where the shoulder was wide enough to allow for safe stopping of the sampling vehicle