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HomeMy WebLinkAbout15- Task Order Tetra Tech for Corrective Measures Assessment Design and ImplementationaTETRA TECH Attachment A Task Order Corrective Measures Assessment Design and Implementation Bozeman Landfill Bozeman, Montana CLIENT: The City of Bozeman P.O. Box 1230 Bozeman Montana 59711-1230 April 3, 2015 CONSULTANT: Bozeman MT 59715 Tetra Tech, Inc. 851 Bridger Drive, Ste 6 Attention: Mr. Rick Hixson, PE Attention: Mr. Larry Cawlfield, PE INTRODUCTION The Story Mill landfill operated from the 1970s through approximately 2008 with both an unlined and lined cell used for the disposal of municipal refuse. The unlined cell was closed in the 1995, and the lined cell was closed in 2010. Investigations conducted by the City during 2013 and 2014 identified the presence of volatile organic compounds (VOCs) in soil gas both on the landfill property and in the adjacent Phase 3 of Bridger Creek Estates neighborhood. Sub -slab depressurization systems were installed in most of the homes in the Phase 3 neighborhood to break the possible pathway of VOCs in soil gas migrating from the landfill property toward the homes. Remediation of the source of the VOCs and/or establishing a barrier to prevent their migration off the landfill property was identified as the next step in the project. The City submitted a Revised Corrective Measures Assessment (CMA) to do this. The Department of Environmental Quality recently approved the Revised CMA and directed the City to implement the selected alternative (Alternative F). This Task Order is directed at developing and implementing Alternative F. SCOPE OF WORK This scope of work covers the implementation of Alternative F starting with preparation of a Selected Remedy Report, development of engineering plans and specifications for the selected remedy (Alternative F), development of construction quality assurance (CQA), construction quality control (CQC) plans, assisting the City with bidding the project, providing construction oversight, overseeing system startup and shakedown, adjustment and monitoring of the system during the first year of operation, and a one-year warranty inspection. Details of the work are described in the following sections. TASK 100 SELECTED REMEDY REPORTING Objectives: • Prepare a Selected Remedy Report describing Alternative F that meets the requirements of ARM 17.50.1309. • Prepare Plans and Specifications for implementation of Alternative F. Prepare Construction Quality Assurance and Construction Quality Control Plans for construction as required in ARM 17.50.1309. Coordinate with the City on the advertising, receipt and evaluation of bids. Tetra Tech 303 Irene Street; Helena, MT 59601 Tel 406.443.5210 Fax 406.449.3729 tetratech.com Task Order for Corrective Measures Assessment Design and Implementation Bozeman Landfill Remediation April 3, 2015 Page 2 of 6 The following paragraphs include detailed descriptions of the scope of work to accomplish these objectives. Subtask 110 Selected Remedy Report Tetra Tech will prepare a Selected Remedy Report that meets the requirements of ARM 17.50.1309. The report will use information from the Revised CMA describing Alternative F that describes generally the long and short term effectiveness of the selected alternative, how it ensures that groundwater standards will be met, interim and short term risks that may occur while it is being constructed, reliability of the selected alternative, and all of the other requirements of ARM 17.50.1309. Based on our discussion with DEQ regarding this report, there is little new information in this report that is not already in the Revised CMA. Subtask 120 Construction Quality Control and Quality Assurance Tetra Tech will prepare two detailed reports describing Quality Control and Assurance measures that will be followed during construction of Alternative F. Quality Control and Quality Assurance (QC/QA) reports will detail team members and their roles in the QA/QC process, required personnel qualifications and certifications, materials requirements and submittals, Quality Control testing and frequency of testing and Quality Assurance measures. Tetra Tech will develop QA/QC measures in conjunction with our 90%/100% Designs (see below). As with our 90%/100% designs, we will issue a draft version for the City's review and will incorporate the City's comments into our final plan for submission to DEQ. Subtask 130 Basis of Desian Report/ 30% Design As a pre -cursor to detailed design, Tetra Tech will prepare a Basis of Design Report. This report will summarize design criteria, identify assumptions and data gaps, and provide conceptual drawings of the proposed system layout and Process and Instrumentation Diagrams (P&ID) where applicable. Tetra Tech has found that such a document is essential in establishing a complete understanding of City's expectations before we begin the design of the system. Tetra Tech will meet with the City to present the Basis of Design Report. During the same time frame, Tetra Tech will prepare a 30% set of Design Plans and Specifications for Alternative F. The 30% Design Drawings will consist of draft P&ID Diagrams for major components, a site plan and layouts for major components. Sheets for details and other items not completed for the 30% Design will be identified but not completed. The 30% Specifications will consist of a list of proposed work items and an annotated outline of Special Provisions for each work item. We will also prepare an Engineer's Estimate for the work items that is consistent with the 30% Design. We understand that the City uses the Montana Public Works Standard Specifications (MPWSS) and revisions adopted by the City and will use these as we develop our special provisions. The MPWSS are a reasonable approach to Standard Specifications for this project. However we expect that they will not cover all the aspects of this project including the electrical and controls, mechanical and other miscellaneous aspects of this project. Tetra Tech will develop or use existing specifications that it has already developed for those aspects of this project not adequately covered by MPWSS. TETRA TECH Task Order for Corrective Measures Assessment Design and Implementation Bozeman Landfill Remediation April 3, 2015 Page 3 of 6 We would expect to meet with the City to present the 30% Design at the same time that we discuss our Basis of Design Report. Because of the relatively short time frame (90 days) in which this and other tasks must be completed, it is important that the City will be able to review the Basis of Design and 30% Design in four or fewer working days. Following the review meeting with the City, Tetra Tech will finalize specifications and drawings for the skid or skids that will become the platforms for the vacuum blowers, compressors and flare for the new system and will place the order for these items with a vendor. This is a long lead time item and, without pre -ordering, this item will significantly slow the completion of the installation of this system. Tetra Tech will coordinate all aspects of the order with the vendor as a part of this task. Subtask 140 90% Design and 100% Designs Following review of the 30% Design, Tetra Tech will flesh out and revise the 30% Design Drawings and Specifications to a 90% design level. At this level, all sheets will be completed and detailed and specifications for each work item will completely detail the materials, work scope, methods and submittals that will be required. We envision that the plans will consist of major sections for each of these major components of the proposed system. The major components (unless modified during the 30% Design Review) will include the following: 1. Flare Station including compressors and vacuum blowers 2. Soil Vapor Extraction Wells, Air Injection Wells and Sparging Wells 3. Condensate and Leachate Collection System 4. Buried piping and headers For each of these major components we anticipate completing drawings showing aspects of each major component related to the following specialties if applicable: 1. Site plans and profiles 2. Piping and Instrumentation Diagrams 3. Electrical Single Line Diagrams 4. Controls and Instrumentation 5. Earthwork and Grading 6. Civil, Structural and Foundation Concurrent with the development of Drawings, Tetra Tech will complete Specifications for the Project to a 90% level of design and will update its Cost Estimate. Following completion of the 90% Design, Tetra Tech will meet with the City to present the 90% Design. As with the 30% Design, it will be important for the City to be able to review and provide comments on the 90% Design in four or fewer days. Following the City's review, Tetra Tech will revise and incorporate comments as necessary to complete the final (100%) Design for submittal to DEQ. If DEQ supplies comments or questions regarding the design submittal, Tetra Tech will reply to those comments or incorporate changes into the drawings and specifications as warranted. For purposes of this task order, we have assumed that comments or changes from DEQ or the City will not be extensive or result in extensive design changes. As a part of this task, Tetra Tech will prepare and submit a modification to the City's Air Quality Permit. TETRA TECH Task Order for Corrective Measures Assessment Design and Implementation Bozeman Landfill Remediation April 3, 2015 Page 4 of 6 TASK 200 BIDDING AND CONSTRUCTION OVERSIGHT Following approval of the plans and specifications by DEQ, Tetra Tech will assist the City in implementing the approved system. During the bidding process, Tetra Tech will supply and track plan sets, attend pre-bid walkthroughs, provide input on any questions posed by Contractors, and evaluate bid tabs for unbalancing or other irregularities. During construction, Tetra Tech will provide near full-time oversight. This will include review of and approval of submittals, on-site inspection and oversight of the Contractor's daily activities, attendance at weekly coordination meetings, Quality Assurance testing, preparation and/or review of pay requests and change orders, preparing well logs, and troubleshooting when unexpected conditions are encountered. On project completion, Tetra Tech will prepare as -built drawings and will also prepare a final construction report that summarizes project milestones, construction issues, pay requests, change orders, construction photos, and related project documentation. TASK 300 SYSTEM STARTUP AND YEAR ONE OPERATION Following completion of construction of the system, Tetra Tech will start the system, tune components to the extent necessary and operate the system during its first year of operation. We anticipate that during startup of the system, there will be considerable monitoring of methane, oxygen, temperature, vacuum, water levels, VOCs and other analytes in the new LFG wells, SVE wells, Air Sparging Wells, off-site soil gas probes and Air Injection wells. We anticipate that there will be daily monitoring and adjustment initially which should slowly taper off to weekly and then monthly monitoring. During this first year of operation, Tetra Tech will create an Operations and Maintenance Manual that describes system components, establishes their operating points and recommends a maintenance schedule. During this first year of operation, Tetra Tech will report to the City in monthly reports the status of the startup and operation. TASK 400 ONE-YEAR WARRANTY INSPECTION/ANNUAL PERFORMANCE REPORT Just prior to the expiration of the one-year contractual warranty, Tetra Tech will conduct a thorough evaluation of all the components of the construction items. Aboveground components will be cycled through their entire range of operation. Below ground components will be inspected with a downhole camera (where possible) or otherwise pressure tested (where possible). Tetra Tech will coordinate with the City and with the Contractor to ensure that any components that are not operating per project specifications are replaced under warranty. At about the same time as the one-year warranty inspection, Tetra Tech will prepare the first Annual Performance Monitoring Report. This report will address the effectiveness of the remedy to control VOCs and to reduce groundwater contamination. The report will include all data collected from the system with appropriate statistical analysis and an estimate of the VOC mass removed by the system. Operational and analytical data from the home mitigation systems will also be included to the extent necessary to show if or how Alternative F implementation may be affecting soil gas migration downgradient. TETRA TECH Task Order for Corrective Measures Assessment Design and Implementation Bozeman Landfill Remediation April 3, 2015 Page 5 of 6 TASK 500 PROJECT MANAGEMENT This task will consist of general oversight of the staff, schedule and budget management and tracking, attendance at monthly progress or special meetings with the City, and preparation of weekly email updates for the City, written monthly status reports and related project communications. Costs for this item have been included until completion of the Annual Performance Monitoring Report. COMPENSATION Estimated costs to complete the foregoing scope of services are not to exceed $288,379. A breakdown of these proposed expenditures is contained in the attached cost estimate. The services will be conducted on a lump sum basis as described in the Contract between the City and Tetra Tech. Special Conditions Execution of this Task Order constitutes acceptance of all terms and conditions contained in Tetra Tech's Professional Services Agreement with the City of Bozeman, dated April 15, 2014. CLIENT: •11".50-3111 By: CLQn��—A , Its: c 0 Date: `1 2-0— 1 �— CONSULTANT: Tetra Tech By: C41-S)a Its: Project Manager Date: _ April 3, 2015 NOTICE OF CONFIDENTIALITY This Task Order (including attachments) contains information confidential to Tetra Tech, Inc., its subsidiaries, and subcontractors. It is intended only for City of Bozeman to consider Tetra Tech providing professional services at the Bozeman Landfill. Any other use is prohibited, without the prior written consent of Tetra Tech. TETRA TECH Task Order for Corrective Measures Assessment Design and Implementation Bozeman Landfill Remediation April 3, 2015 Page 6 of 6 Table 1 Estimated Costs for Alternative F Design and Implementation Task Description Estimated Cost Selected Remedy Reporting Selected Remedy Report $5,408 CQC/CQA Plans $5,284 Basis of Design/30% Design $20,528 90% and 100% Design $80,134 Comment Responses and Changes $7,960 Air Permit Modifications $3,804 Subtotal $123,118 Bidding and Construction Bidding $3,294 Construction $40,528 Subtotal $43,822 System Startup and Year One Operation Startup $27,210 Operation $44,196 Subtotal $71,406 One Year Warranty Inspection Inspection $8,124 Annual Report $11,312 Subtotal $19,436 Project Management Project Management $26,077 Health and Safety $4,520 Subtotal $30,597 Total $288,379 TETRA TECH