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Guidelines for Managing Geotechnical Risks in Design–Build Projects (2018)

Chapter: Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools

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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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Suggested Citation:"Appendix C - Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools." National Academies of Sciences, Engineering, and Medicine. 2018. Guidelines for Managing Geotechnical Risks in Design–Build Projects. Washington, DC: The National Academies Press. doi: 10.17226/25262.
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C-1 Appendix C provides additional detail for the five geotechnical risk management strategies, the four project phase-based methods, and the 25 risk management tools. The methodology described by Anderson et al. (2007) begins by identifying the causal factors for the problems that the strategies developed must address. The following are the major factors for which a strategy is needed to resolve common issues present in most DB projects. The following list is not intended to be comprehensive but general enough to apply to most, if not all, DB project delivery environments. • Delays due to untimely actions by third party stakeholders. • Inefficiencies in the project delivery process due to failure to include salient geotechnical risk issues in the procurement process. • Lost opportunities to avoid difficult geotechnical conditions. • Claims due to DSC. • Delays due to utility coordination and location failures. • Poor quality post-award geotechnical investigations. C.1 Strategies Below is the corresponding list of respective strategies to address the causes of geotechnical- related problems on DB projects. 1. Implement early contractor design involvement through encouraging geotechnical ATCs during procurement. 2. Use DB process to address other subsurface issues like utility company timeliness by involving third party stakeholders as early as practical in project development and delivery. 3. Raise the visibility of geotechnical issues in DB projects to ensure competing contractor teams understand the level of criticality on each project. 4. Avoid DSC claims through enhanced contract mechanisms designed specifically for address- ing geotechnical risks. 5. Promote an atmosphere of life cycle-based design and construction decision making with respect to geotechnical risk on DB projects. C.2 Methods A method is a “regular, systematic way of accomplishing something.” Thus, in the geotechni- cal risk context, the method will correspond to the particular stage of project delivery in which the project is being considered. Each stage has “regular, systematic” procedures that constrain A P P E N D I X C Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools “A strategy is a plan of action intended on accomplishing a specific goal. Strate- gies typically address a specific problem and are formulated to address a prob- lem’s root cause. . . . The strategy is implemented through a method. A method is a means or manner of proce- dure, especially a regular and systematic way of accomplishing something. . . . A method is then implemented using a tool. A tool is something used in the performance of an operation.” Anderson et al. (2007)

C-2 Guidelines for Managing Geotechnical Risks in Design–Build Projects the ability of the project team’s use of the tools found by and developed for this research. There- fore, the methods appropriate to this work are defined as follows: • Pre-advertising geotechnical risk management. This method consists of the typical activities undertaken during preliminary engineering to identify and quantify geotechnical risks for inclusion in a DB RFP. • Procurement geotechnical risk management. This method consists of activities under- taken to refine the DB project’s geotechnical risk profile during competitive DB proposal preparation. • Pre-construction geotechnical risk management. This method consists of activities undertaken after the award of the DB contract during the design phase of the project. • Construction geotechnical risk management. This method consists of activities undertaken after the award of the DB contract during the construction phase of the project. C.3 Tools Table C.1 lists the 25 tools identified for implementing geotechnical risk management as well as the source of each tool. A state abbreviation followed by a plus sign indicates that more than one DOT has successfully implemented the given tool. The list below contains the definition for each tool and, where applicable, examples of DB RFP clauses that were used in the tool’s implementation. 1. Flexible footprint for NEPA clearance. This tool depends on the agency selecting DB project delivery early enough to influence the final form of the NEPA clearance. In essence, this tool seeks to provide as much flexibility in the final permit as practical to avoid the potential that attractive geotechnical design solutions are not unintentionally disallowed by commitments made to obtain the permit in a timely manner. No clause available. This tool is designed to make planners and project developers aware of the potential for options to address various geotechnical issues as early as possible to permit the maxi- mum level of technical flexibility during the final design and construction phases as well as to leave open as many opportunities for ATCs without the need to trigger a rereview of environmental and other clearances. 2. Furnish geotechnical baseline report (GBR). Developed by the owner, who collects all the relevant data from similar previous projects and the test results for the current project and assembles the information into what will serve as the geotechnical baseline for bidders for decreasing geotechnical uncertainty during procurement, which can make proposals received more competitive. No clause available. This tool is self-explanatory. 3. Geotechnical conditions database. The advancement of computing power and the reduction in data storage costs have made it feasible for agencies to create corridor-level geotechnical databases consisting of all the data gathered in past projects. Those databases can then be mined to furnish information on site conditions for upcoming projects. Project CAD Files, Soils Borings and Geotechnical Reports: The Department makes no repre- sentations or warranties, express or implied, with respect to the reuse of the data provided herewith, regardless of its format or the means of its transmission. There is no guarantee or representation to the user as to the accuracy, currency, suitability, or reliability of this data for any purpose. The user accepts the data “as is”, and assumes all risks associated with its use. By acceptance of this data, the user agrees not to transmit this data or provide access to it or any part of it to another party unless the user shall include with the data a copy of this disclaimer. The Department assumes no responsibility for actual or consequential damage incurred as a result of any user’s reliance on this data (Minnesota DOT 2010).

Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools C-3 # Tool Source Tools Used During RFP Development 1 Flexible footprint for NEPA clearance MO 2 Develop and furnish GBR in RFP WA+ 3 Geotechnical conditions database VA 4 Site conditions history from property owners during ROW acquisition MN 5 Prescriptive geotechnical design UT+ 6 Performance specifications for post-construction performance (subsidence, etc.) MN+ Tools Used During Procurement and Award 7 Include differing site conditions clause SC+ 8 Progressive DB MD 9 Request of geotechnical and/or utilities ATCs CA+ 10 Define no-go zones for geotechnical ATCs UT+ 11 Competitor designated boring locations UT+ 12 Competitors permitted to conduct supplementary borings at own expense. MN+ 13 Unit prices for contaminated material, over-excavation, etc. MT+ 14 Weight geotechnical evaluation criteria MI+ 15 Include life-cycle criteria in best value award scheme TX+ Tools Used During Post-Award 16 Scope validation period VA 17 Multiple NTPs with one designated for geotechnical investigation, design, and a second specifically to commence excavations, utility work, etc. UT 18 Contractor produced GBR-C OH 19 Negotiated GBR interpretation WA+ 20 Differing site conditions allowance WA+ 21 Contaminated material allowance MN+ 22 Unforeseen utilities allowance KY 23 Assign design-builder responsibility for utility coordination TX+ 24 Validate proposed life cycle elements during design CA 25 Encourage life cycle related value engineering proposals from subcontractors CA+ Table C.1. Geotechnical risk management tools identified in the research.

C-4 Guidelines for Managing Geotechnical Risks in Design–Build Projects 4. Site conditions history from property owners during ROW acquisition. Property owners will often have knowledge of a given parcel’s history and may be able to provide information with regard to previous utilities and structures. Additionally, they may have knowledge of the presence of buried material such as demolition materials from previous structures, as well as provide potential warnings that contaminated material may be present. The tool merely adds these questions to the ROW acquisition process and may trigger the need to conduct sampling during preliminary engineering. No clause available. This tool is self-explanatory. 5. Prescriptive geotechnical design. DB project delivery is by definition performance-based in that the contract is awarded before the design is complete. However, since geotechnical issues are often on the critical path, this tool involves the agency prescribing a geotechnical design approach with which it is comfortable and stating in the DB RFP that no deviations will be permitted. The result saves time during initial design reviews of subsurface features of work, which potentially allows those design packages to be released for construction as early as practical if desired. The Proposal may not include any qualifications, conditions, assumptions, exceptions to, or devia- tions from the requirements of the RFP, except as contained in pre-approved ATCs (including condi- tionally pre-approved ATCs that have been revised to satisfy any conditions to approval) (California DOT 2013). 6. Performance specifications for post-construction performance (subsidence, etc.). To mitigate potential geotechnical-related failures in the operation phase of the project, an owner might include a requirement for specific geotechnical-related performance warranties by the contractor. Roadway embankments constructed under this Contract shall meet the following performance criteria: Engineering analysis shall show that total settlement at any point on constructed embankment will not exceed 4 inches during the period ranging from Substantial Completion to 25 years after Substantial Completion. Global stability calculations shall use a minimum Safety Factor of 1.5. Lateral squeeze calculations shall use a minimum Safety Factor of 2.0. Ground improvement techniques (and/or lightweight fill material) may be used to improve the under- lying poor foundations soils. Any ground improvement techniques used in design or construction shall follow the guidelines presented in the most recent FHWA publication on ground improvement. The Contractor shall monitor settlement of underlying foundation soils prior to any fill being placed, through construction and through the warranty period. Roadway shall not be paved until settlement data shows less than 1 inch of total settlement occurring for eight consecutive weeks with settlement readings taken on a weekly basis. Readings taken during cold weather months (November through April) will not be allowed to count for this settlement period. Settlement data shall be presented in tabular and graphical format (settlement in inches plotted on the y-axis and time in days plotted on the x-axis). The Contractor shall provide, install, and monitor geotechnical instrumentation to measure total settlement of constructed embankments during the Contract and Warranty period. Settlement plates (flat plates with pipe extensions) shall not be used for measuring settlement. Within one week after Substantial Completion of the roadway, the Contractor shall measure and submit as-built profiles of the roadway for northbound centerline, northbound 12 feet left of centerline, north- bound 12 feet right of centerline, southbound centerline, southbound 12 feet left of centerline, south- bound 12 feet right of centerline. The Contractor shall measure these same profiles at the conclusion of the Warranty period. If total settlement exceeds 4 inches at any point along the profiles, the Contractor shall submit a settle- ment correction plan for Approval. This correction plan shall consist of remedial measures up to, and possibly including, major reconstructive efforts to correct the ongoing settlement problem (Minnesota DOT 2010).

Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools C-5 7. Include differing site conditions (DSC) clause. Much of the geotechnical claim generally falls under changes due to DSC. The typical DSC clause provides broad relief to a contractor for site conditions that differ materially from what is expected according to the contract docu- ments. The FHWA does not have a DSC mandate for DB projects. Nevertheless, many state DOTs use a DSC clause in their DB contracts. (i) During the progress of the work, if subsurface or latent physical conditions are encountered at the site differing materially from those indicated in the contract or if unknown physical conditions of an unusual nature, differing materially from those ordinarily encountered and generally recognized as inherent in the work provided for in the contract, are encountered at the site, the party discover- ing such conditions shall promptly notify the other party in writing of the specific differing conditions before the site is disturbed and before the affected work is performed. (ii) Upon written notification, the engineer will investigate the conditions, and if it is determined that the conditions materially differ and cause an increase or decrease in the cost or time required for the performance of any work under the contract, an adjustment, excluding anticipated profits, will be made and the contract modified in writing accordingly. The engineer will notify the contractor of the determination whether or not an adjustment of the contract is warranted. (iii) No contract adjustment which results in a benefit to the contractor will be allowed unless the contractor has provided the required written notice. [U.S. Code, Differing Site Conditions, Title 23 CFR 635.109(c) (2013)] 8. Progressive design-build (PDB). PDB’s attraction is the ability to negotiate the geotechnical risk after award and after the geotechnical investigation has been completed rather than depending on the DSC clause to allocate the subsurface risk. With PDB, the first design and construction package released for construction could commence the subsurface investiga- tion and conduct selected excavation on the project site to identify where the geotechnical issues will be encountered and their magnitude. Thus, a fair and equitable amount for the realized subsurface risk can be established. This eliminates the need for adding unnecessary contingencies in the price, as the uncertainty of the subsurface conditions is eliminated early in the project. This Progressive Design-Build (PDB) contract is a two-phase, fixed value contract. Phase one of the contract will be for the selected Design-Builder to provide design and preconstruction services to SHA to develop the project to the level necessary to submit a price for construction for work packages proposed by the Design-Builder. Once the design has been completed to the necessary level for any work package to submit a price, the SHA will attempt to reconcile a Construction Agreed Price (CAP) for the construction of that work pack- age. As multiple packages are allowed and anticipated, multiple CAPs may be agreed upon as long as the overall sum of all CAPs does not exceed the contract’s fixed value. If the SHA agrees to a CAP, then notice to proceed for phase two construction services would be issued for that package. The SHA reserves the right to not proceed with phase two of the contract and bid a package competitively if a CAP cannot be reached. If SHA chooses to deliver the project by other means, the selected Design-Builder will not be permitted to submit a proposal or bid. The intent is to form a partnership with the owner (SHA) and the Design-Builder. The goals of this partnership are to mitigate risk, streamline the design process, improve the decision-making process with better information, and develop a project that meets the project goals while adhering to the budget. We anticipate the involvement of the Design-Builder will help reduce errors in design, maximize the achieve- ment of project goals, improve the overall constructability of the project and support the Practical Design process. The fixed value of the contract is an aggregate of the Design-Builder’s Design and Preconstruction services fee, the Design-Builder’s Construction Management Fee, and the Construction services costs. Construction Services will include all CAPs, costs for any necessary right-of-way acquisition, and costs for any utility relocations required due to the construction of the contract. The fixed value of the contract will be $100,000,000 (Maryland State Highway Administration 2016). 9. Request of geotechnical/utility-related alternative technical concepts (ATCs). ATCs allow proposers to submit alternative solutions to potential subsurface problems before the con- tract is awarded; request ATCs (which the agency will hold confidential and preapprove if

C-6 Guidelines for Managing Geotechnical Risks in Design–Build Projects applicable) to identify geotechnical issues and enhance innovation in geotechnical design and subsurface construction means and methods. The ATC process allows innovation, flexibility, time and cost savings on the design and construction of Design-Build Projects while providing the best value for the public. The alternative technical concept shall provide an approach that is equal to or better than what is required by the Request for Proposal (RFP), as determined by the Department. Concepts which reduce scope, quality, performance, or reli- ability should not be proposed. A proposed concept is not an ATC if it is contemplated by the RFP. One-on-One ATC discussion meetings may be held in order for the Design-Build Firm to describe pro- posed changes to supplied basic configurations, Project scope, design criteria, and/or construction criteria. Each Design-Build Firm with proposed changes may request a One-on-One ATC discussion meeting to describe the proposed changes. The Design-Build Firm shall provide, by the deadline shown in the Schedule of Events of this RFP, a preliminary list of ATC proposals, to be reviewed and discussed during the One-on-One ATC discussion meeting. This list may not be inclusive of all ATCs to be discussed but it should be sufficiently comprehensive to allow the Department to identify appropriate personnel to participate in the One-on-One ATC discussion meeting. The purpose of the One-on-One ATC discussion meeting is to discuss the ATC proposals, answer questions that the Department may have related to the ATC proposal, review other relevant information and when possible establish whether the proposal meets the definition of an ATC thereby requiring the submittal of a formal ATC submittal. The meeting should be between representatives of the Design-Build Firm and/or the Design-Build Engineer of Record and District/Central Office staff as needed to provide feedback on the ATC proposal. The following requirements described by this RFP shall not be modified by the Design-Build Firm: The following requirements described by this RFP may be modified by the Design-Build Firm pro- vided they are presented in the One-on-One ATC discussion meeting and submitted to the Depart- ment for review and approval through the ATC process described herein. The Department may deem a Proposal Non-Responsive should the Design-Build Firm fail to present and obtain Department approval of the proposed alternates through the ATC process (Florida DOT 2013). 10. Define no-go zones for geotechnical ATCs. ATC no-go zones are those areas of the geotechnical baseline design that may not be proposed for change during the DB procurement. The following geometric design components are off-limits to change due to an ATC: a. The grade and alignment of the tie-in of the eastbound/westbound ramps (parkways) at Cass Avenue shall not change from as shown on contract documents. b. The grade and alignment of the tie-in of the eastbound and westbound ramps at the Missouri Approach to the MRB shall not change as shown on the contract documents. c. Unless it is a weekend closure due to a bridge demolition, at least two lanes of traffic in each direc- tion on Interstate 70, 55 and 44 throughout the project area shall be maintained at all times. d. Any change shall be compatible with the Phase II full-build interchange (Missouri DOT 2010). 11. Competitor designated boring locations. To reduce geotechnical risk by conducting subsur- face explorations (borings) at strategic locations to help provide reasonable geotechnical parameters to the bidders. Additional borings are made available to all competitors, but sometimes the agency performs more borings to avoid giving away the location requested by a proposer so the competitive advantage is retained; an important element for the success of the project during the procurement phase is to have sufficient geotechnical information that allows competitors to price the project without excessive contingencies. The Department recognizes that additional geotechnical information is necessary to finalize the Project designs. Therefore, the Department will conduct a Supplemental Boring Program as part of the procure- ment process that will allow the Proposers to request additional borings and geotechnical testing. Each Proposer will be allowed to request up to three (3) over-water borings in the Fore River channel, two (2) on-land borings on the Portland side of the Fore River, and one (1) on-water or on-land boring on the South Portland side of the river, for a total of six (6) additional test borings per Proposer (Maine DOT 2010). 12. Competitors permitted to conduct supplementary borings at own expense. Allow competing design–builders to conduct their own pre-bid geotechnical investigations before developing their proposals to reduce geotechnical uncertainty; an important element for the success of

Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools C-7 the project during the procurement phase is to have sufficient geotechnical information that allows competitors to price the project without excessive contingencies. For all additional subsurface explorations performed at the Proposer/DBT’s expense, the Pro- poser/DBT shall secure an access permit from the appropriate agency, if required, which may require the preparation of an equipment access plan, description of equipment types, a plan of the test locations, etc. The Proposer/DBT shall adhere to all traffic control requirements when taking samples on existing road- ways. A traffic control plan may be required. Additional subsurface explorations may take place at any time before or after submission of the Proposal. The Proposer/DBT shall not enter any private property without permission from the private property owner. Prior to project award, the Proposer shall not enter any private property acting as an agent of the State of Ohio. If prior to award, the Proposer wishes to enter State of Ohio property, they must apply for the proper permit through the Department Office of Permits. After award, the selected DBT may enter any State of Ohio property in the project limits at any time, but parcels not yet purchased by the State of Ohio for this project may not be accessible without specific per- mission from the property owner. All subsurface explorations, including sampling and laboratory testing, shall be performed in accordance with the latest Specifications for Geotechnical Explorations, AASHTO standards, and ASTM standards. The DBT shall perform all laboratory testing at a Department pre- qualified geotechnical testing laboratory (Ohio DOT 2011). 13. Unit prices for contaminated material, over-excavation, etc. A formalized geotechnical risk allocation technique to draft the contract provision that uses selective unit pricing, which provides an effective means for managing geotechnical quantity uncertainty. The Bid Price Proposal form will include unit prices for the items indicated [rock scaling], a lump sum price for the remainder of the project scope and the completion date proposed by the Firm. The unit prices will include all costs associated with the construction of the items indicated. Each unit price will be multiplied by the quantity provided by MDT to determine the total amount for each of the unit price items. The Total Lump Sum for the project will be calculated by adding the extended sum of the unit price items with the lump sum amount for the remainder of the project scope. This total lump sum will be the final contract amount. The lump sum price will include costs for all design, surveying, geotechnical work, engineering services, Quality Management Plan, construction of the project (all items except the unit price items) and all other work necessary to fully and timely complete the project in accordance with the Contract Documents. The lump sum price will also include all job site and home office overhead and profit. It is understood payment of the lump sum amount for the project will be full, complete and final compensation for all work required to complete the project. If project overruns or under runs occur at sites, the unit prices will be utilized to extend or reduce the work at other sites to maximize the amount of work accomplished for three million dollars (Montana DOT 2011). 14. Weight geotechnical evaluation criteria. Tailor relative geotechnical weight for the contractor selection process in each DB project. Table C.2 is an example from Virginia DOT. 15. Include life cycle criteria in best value award scheme. Because design is where the quality standards for construction are established, it is important that agency expectations for post-construction life cycle performance be articulated in the solicitation and used to identify successful approaches for managing geotechnical risks across the DB project’s life cycle as Subsections Rating Weight TOTAL 100 points 4.2 4.3.1 4.3.2 4.3.3 4.3.4 4.3.5 4.3.6 4.3.7 20 25 10 25 5 10 5 Pass/Fail Qualifications and Experience Quality Assurance/Quality Control Design Factors Geotechnical Construction Factors Schedule Safety Disadvantaged Business Enterprise Table C.2. Example of Virginia DOT weighting scheme.

C-8 Guidelines for Managing Geotechnical Risks in Design–Build Projects well as discuss those practices that did not adequately address the geotechnical requirements and caused the agency to hold geotechnical liability that it had hoped to shed. Technical Approach and Innovations in the Design and Construction of the Project (Section 6) Examples of technical innovations may include, but should not be limited to: Drainage Design Improvements: improvements to the drainage design that increases the level of treat- ment, increases infiltration, and/or reduces the life-cycle costs of stormwater management facili- ties, such as reduction in volume of ponds. Bridges: design and construction of the I-405 southbound bridge over I-90 (including ramps), the wid- ened northbound I-405 bridge over Coal Creek Parkway, the widened I-405 northbound bridge over BNSF, and the widened southbound I-405 bridge over SE 8th St that: • Significantly reduces the schedule • Minimizes impact to the traveling public • Optimizes the mainline geometrics • Minimizes long-term maintenance costs (Washington State DOT 2006) 16. Scope validation period. A period of time incorporated into the contract to allow the con- tractor to discover any site conditions that differ from owner-furnished information early in the project. After the end of the scope validation period, the design–builder’s claim rights are waived for items not previously raised. This approach allows for an early resolution of geotechnical-related issues and establishes a limit for the owner’s liability by assigning a specific timeframe for differing site conditions claims. 2.2 Scope Validation and Identification of Scope Issues 2.2.1 Scope Validation Period. The term “Scope Validation Period” is the period of time that begins on Design-Builder’s receipt of Department’s Notice to Proceed and extends for one hundred twenty (120) days from such date of receipt, unless otherwise stated in Exhibit 1. During the Scope Validation Period, Design-Builder shall thoroughly review and compare all of the then-existing Contract Documents, including without limitation the RFP Documents and the Proposal, to verify and validate Design-Builder’s proposed design concept and identify any defects, errors, or inconsistencies in the RFP Documents that affect Design-Builder’s ability to complete its proposed design concept within the Contract Price and/or Contract Time(s) (col- lectively referred to as “Scope Issues”). The term “Scope Issue” shall not be deemed to include items that Design-Builder should have reasonably discovered prior to the Agreement Date. 2.2.2 Scope Validation Period for Non-Accessible Areas of the Site. The Parties recognize that Design-Builder may be unable to conduct the additional geotechnical evaluations contem- plated by Section 4.2.2 below because it will not have access to certain areas of the Site within the Scope Validation Period set forth in Section 2.2.1 above. Design-Builder shall notify Department at the meeting set forth in Section 2.1.2 of all such non-accessible areas and the dates upon which such areas are expected to become accessible. If Department agrees that such areas are non-accessible, then, for the limited purpose of determining Scope Issues that directly arise from geotechnical evaluations for such areas, the term “Scope Vali- dation Period” shall be deemed to be the thirty (30) day period after the date the specified area becomes accessible for purposes of conducting the geotechnical evaluation. 2.2.3 Submission Requirements for Scope Issues. If Design-Builder intends to seek relief for a Scope Issue, it shall promptly, but in no event later than the expiration of the Scope Validation Period, provide Department in writing with a notice (“General Notice”) of the existence of such Scope Issue, which General Notice shall generally explain the basis for such Scope Issue. Within twenty-one (21) days of the General Notice of a Scope Issue, Design-Builder shall provide Department with documentation that specifically explains its support for the Scope Issue (“Supporting Documentation”), which Supporting Documentation shall include, among other things: (a) the assumptions that Design-Builder made during the preparation of its proposal that form the basis for its allegation, along with documentation verifying that it made such assumptions in developing its proposal; (b) an explanation of the defect, error or inconsistency in the RFP Documents that Design-Builder could not have reasonably identi- fied prior to the Agreement Date; and (c) the specific impact that the alleged Scope Issue has had on Design-Builder’s price and time to perform the Work. For the avoidance of doubt: (1) Design-Builder shall not be entitled to raise in its Supporting Documentation any Scope Issues that were not previously addressed in a General Notice; and (2) Design-Builder shall

Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools C-9 have no right to seek any relief for any Scope Issues that have not been specifically identified in a General Notice provided to Department during the Scope Validation Period. 2.2.4 Resolution of Scope Issues. Within a reasonable time after Department’s receipt of the Supporting Documentation described in the Section 2.2.3 above, the Parties shall meet and confer to discuss the resolution of such Scope Issues. If Department agrees that Design-Builder has identified a valid Scope Issue that materially impacts Design- Builder’s price or time to perform the Work, a Work Order shall be issued in accor- dance with Article 9 hereof. If Department disagrees that Design-Builder has identified a valid Scope Issue that materially impacts Design-Builder’s price or time to perform the Work, then Design-Builder’s recourse shall be as set forth in Article 10. Notwithstand- ing anything to the contrary in the Contract Documents or as a matter of law, Design- Builder shall have the burden of proving that the alleged Scope Issue could not have been reasonably identified prior to the Agreement Date and that such Scope Issue materially impacts its price or time to perform the Work. 2.2.5 Design-Builder’s Assumption of Risk of Scope Issues. The Parties acknowledge that the purpose of the Scope Validation Period is to enable Design-Builder to identify those Scope Issues that could not reasonably be identified prior to the Agreement Date. By executing this Agreement, Design-Builder acknowledges that the Scope Validation Period is a reasonable time to enable Design-Builder to identify Scope Issues that will materially impact Design- Builder’s price or time to perform the Work. After the expiration of the Scope Validation Period, with the sole exception of those Scope Issues made the subject of a General Notice during the Scope Validation Period and subject to valid requests for Work Orders in accordance with Section 2.2.3 above, the Parties agree as follows: 1. Design-Builder shall assume and accept all risks, costs, and responsibilities of any Scope Issue arising from or relating to the Contract Documents, including but not limited to conflicts within or between the RFP Documents and Proposal; 2. Design-Builder shall be deemed to have expressly warranted that the Contract Documents existing as of the end of the Scope Validation Period are sufficient to enable Design- Builder to complete the design and construction of the Project without any increase in the Contract Price or extension to the Contract Time(s); and 3. Department expressly disclaims any responsibility for, and Design-Builder expressly waives its right to seek any increase in the Contract Price or extension to the Contract Time(s) for, any Scope Issue associated with any of the Contract Documents, including but not limited to the RFP Documents. 2.2.6 Waiver of Rights. The failure of Design-Builder to meet the submission requirements required under Section 2.2.3 above for a Scope Issue, including but not limited to the times for providing notice and documentation of the Scope Issue, shall conclusively constitute a waiver of Design-Builder’s rights to seek relief for such Scope Issue (Virginia DOT 2010). 17. Multiple notices to proceed (NTPs). Using multiple NTPs allows the owner to reduce the risk of differing site conditions by issuing an NTP only for the contractor’s subsurface explora- tion and underground work before releasing the entire scope of work. This way there is a prioritization in removing the uncertainty of the subsurface conditions early in the project so any differing site condition is addressed before advancing to the next stages of the project. 4.1.3 TxDOT anticipates issuing NTP1 concurrently with execution and delivery of this Agreement. Issuance of NTP1 authorizes DB Contractor to perform (or, continue performance of) the portion of the Work necessary to obtain TxDOT’s approval of the component parts, plans and documentation of the Proj- ect Management Plan that are labeled “A” in the column titled “Required By” in Attachment 2-1 to the Technical Provisions. It also authorizes DB Contractor to enter Project Right of Way owned by TxDOT for the purpose of conducting surveys and site investigations, including geotechnical, Hazardous Materials, and Utilities investigations. Refer to Sections 12.1.4 and 15.9 regarding a Price adjustment to be made in certain circumstances if the effective date of the NTP1 is later than 180 days after the Proposal Due Date, and regard- ing DB Contractor’s remedies for certain delays in issuance of NTP1 beyond 365 days after the Effective Date. 4.1.4 TxDOT anticipates issuing NTP2 concurrently with TxDOT’s approval of all the foregoing component parts, plans and documentation of the Project Management Plan and the Project Schedule. Issuance of NTP2 authorizes DB Contractor to perform all other Work and activities pertaining to the Project (Texas DOT 2013). 18. Contractor produced geotechnical baseline report for construction (GBR-C). Developed for the purpose of baselining geotechnical conditions for a project to allocate geotechnical risk

C-10 Guidelines for Managing Geotechnical Risks in Design–Build Projects encountered during construction, the owner collects all the relevant data from similar pre- vious projects and the test results for the current project (geotechnical data report). On the basis of the data collected and test results, the owner prepares a GBR for Bidding (GBR-B). The bidder uses the GBR-B and augments it with its approach and design to develop a new version: the GBR for Construction (GBR-C). It will incorporate the contractors’ inter- pretation and approach and its proposed means and methods. The owner should review the GBR-Cs prepared by bidders and seek clarification on any issues as needed. On the basis of this review, the owner will have the opportunity to seek adjustment of the contract price if appropriate. After the bidder is selected, its GBR-C will be incorporated into the DB contract documents and form the basis for risk allocation during the design-construction phase. The DBT shall use the subsurface exploration information provided in Appendix GE-03, along with any supplemental information gathered to design and construct a microtunnel for installation of storm sewer described in Section 11.4.5. A report specifically addressing the design of the microtunnel and microtunnel construction procedures, as presented in Section 11.4.5, shall be prepared and presented to the Department. The minimum contents of the report are presented in the following paragraphs. The DBT shall clearly identify all planned microtunnel construction procedures, including sequence, limits, equipment, and schedule. The DBT shall perform a comprehensive settlement analysis along the entire alignment of the micro- tunnel, based on the microtunnel construction procedures planned and all necessary pits. This analysis shall include determining the zone of influence from the microtunnel construction. Within this zone of influence, the DBT shall determine all anticipated total and differential settlements and tilt of all structure foundations, abutments, walls and roadway facilities as a result of the microtunnel operations. The DBT shall acquire the existing structure plans from the Department. The plans include, but are not limited to. . . . Data from the plans shall be used to model structure location and weight to determine anticipated structure movement. The DBT shall perform a structural analysis of every structure within the zone of influence to determine allowable substructure and super structure settlement and tilt. The DBT must clearly identify how the allowable values were determined. The DBT shall perform stability and settlement analyses for all pits, including recovery pits, and all structures and roadway facilities within the zone of influence of planned pits. The DBT shall summarize all settlement and stability analyses results, comparing them to allowable values, and identify planned procedures for maintaining settlements of structures within the allowable limits. The procedures may include any one or more of the following: i. Overcut ii. Pressure grouting of the tunnel alignment prior to tunneling iii. Compensation grouting iv. Special equipment requirements v. Alignment change vi. Other ground improvement methods The DBT shall perform a pre-construction survey of the roadway and structures within the zone of influence or within 50 feet of the microtunnel alignment, whichever is greater. The survey shall include ground line cross sections of the roadway every 50 feet along the alignment of the tunnel, extending to 50 feet left and right of the tunnel centerline. The survey shall also include baseline elevation readings of all structure foundations, abutments and walls within the aforementioned limits to establish base line elevations for settlement and tilt recording. Prior to microtunneling, the DBT shall submit a plan for obstruction removal from the heading of the microtunneling face (i.e., boulder or boulders). Provide details on when and if the obstruction will be removed from within the tunnel, when recovery pits will be necessary and the time required to complete each operation. Submit descriptions on how the tunnel face will be maintained in stable conditions during obstruction removal. Provide details on how the settlement will be controlled during the obstruction removal from within the tunnel and how the face of the tunnel will be secured until the recovery pit is constructed (Ohio DOT 2011). 19. Negotiated GBR interpretation. This tool generally involves the use of a GBR-C as described above and a GBR-B (the owner’s GBR used during bidding). After award of the DB contract and the subsequent completion of the GBR-C, the owner and the design–builder compare the two GBRs and agree on how to interpret a final GBR (modified GBR-C) during construction with respect to the contract’s DSC clause. The aim is to mutually agree on what constitutes a material difference and in doing so share the DSC risk on a project specific basis.

Detailed Explanation of Geotechnical Risk Management Strategies, Methods, and Tools C-11 No clause available. Figure C.1 illustrates the process used to mutually negotiate the interpretation of a GBR-C. 20. Differing site conditions allowance. Including a specified dollar amount (allowance) in the RFP Agreement for differing site conditions to mitigate this commonly misallocated geotechnical risk. Notwithstanding the above, the Design-Builder shall be entitled to equitable adjustment adjusting the Contract Price only for the actual, reasonable cost increase resulting from Differing Site Condi- tions, which in the aggregate exceeds $10,000,000.00. The responsibility for the first $10,000,000.00 worth of Differing Site Conditions shall rest solely with the Design-Builder (Washington State DOT 2009). 21. Contaminated material allowance. Including a specified dollar amount (allowance) in the RFP Agreement for testing and handling of hazardous materials to mitigate this commonly misallocated geotechnical risk. Same as Tool 20 but relating to unforeseen contaminated material. 22. Unforeseen utilities allowance. Including a specified dollar amount (allowance) in the RFP Agreement for addressing utilities discovered during construction to mitigate this com- monly misallocated geotechnical risk. Same as Tool 20 but relating to unforeseen utilities. 23. Assign contractor responsibility for utility coordination. Transfer of utility coordination activi- ties from in-house personnel to contractor to enhance collaboration and early contractor involvement. The Design-Builder shall coordinate its design and construction efforts with utility owners as set forth in Part 2, General Provisions of the Contract. All design and construction work performed by the Design- Builder shall be coordinated with the utility owners, and shall be subject to the utility standards and applicable provisions of the Contract Documents. Figure C.1. Use of geotechnical baseline report in DB projects.

C-12 Guidelines for Managing Geotechnical Risks in Design–Build Projects The Design-Builder shall notify the Department at least five working days in advance of each meeting with a utility owner’s representative scheduled by the Design-Builder and shall allow the Department the opportunity to participate in each meeting. The Design-Builder shall also provide to the Department copies of all correspondence between the Design-Builder and any utility owner, within seven days after receipt or sending, as applicable. The Design-Build Firm shall utilize a single dedicated person responsible for managing all utility coordination. This person shall be referred to as the Utility Coordination Manager. The Design-Build Firm’s Utility Coordination Manager shall be responsible for managing all utility coordination (New York State DOT 2013). 24. Validate proposed life cycle elements during design. DB procurements often include both design and evaluation criteria that seek to encourage life-cycle design decision making by the competing proposers. This tool consists of conducting the subsequent life cycle cost analysis to validate that the winning proposal’s betterments indeed reduce the project’s pro- jected life cycle cost from that of the baseline design. No clause available. This tool is self-explanatory. 25. Encourage life cycle related value engineering proposals from subcontractors. Subcontractors are technical specialists in their particular areas of expertise. This is particularly true in areas like jet grouting, seismic retrofits, soil nails, and other geotechnical specialties. They are normally up to date with the state of technology and should be asked to review their scopes of work for potential improvements that would reduce life cycle cost. No clause available. This tool is self-explanatory. References Anderson, S., K. Molenaar, and C. Schexnayder. (2007). NCHRP Research Report 574: Guidance for Cost Estima- tion and Management for Highway Projects During Planning, Programming, and Preconstruction. Transporta- tion Research Board, Washington, D.C. California DOT. (Oct. 1, 2013). Request for Qualifications, State Route 99 Realignment, California DOT, Fresno. Florida DOT. (2013). Design-Build Request for Proposal Template. Florida DOT, Tallahassee. Maine DOT. (Oct. 13, 2010). Request for Proposals. Caribou Connector New Highway and Bridge Construction Design-Build Project. Project No. HPP-STP-6462-500. Maine DOT, Augusta. Maryland State Highway Administration. (2016). Request for Proposals. Progressive Design-Build (PDB) IS 270: Innovative Congestion Management Project—Montgomery and Frederick Counties. Maryland State Highway Administration, Baltimore. Minnesota DOT. (Jan. 13, 2010). Request for Proposals. Book 1–TH 61 Hastings Bridge Design-Build Project. S.P. 1913-64. Minnesota DOT, Metro District, Saint Paul, p. 7. Missouri DOT. (2010). Alternate Technical Concept (ATC) Process for the MRB Missouri I-70 Interchange Project. J6U1086. Missouri DOT, Jefferson City. Montana DOT. (2011). Design-Build Request for Proposal US 2—Rockfall Mitigation, Flathead County. Project SFCN 1-2(169)154. Montana DOT, Helena. New York State DOT. (Dec. 10, 2013). Geotechnical Design Manual. New York State DOT, Albany. Ohio DOT. (2011). Request for Proposals. I-70/I-71 Innerbelt, Columbus Crossroads. Ohio DOT, Columbus. Texas DOT. (2013). Request for Proposals. Loop 1604 Western Extension Project Design-Build Agreement. Texas DOT, Austin. Virginia DOT. (2010). General Conditions of Contract Between Department and Design-Builder. Virginia DOT, Richmond. Washington State DOT. (2009). Request for Proposals. SR 520 Pontoon Construction Design-Build Project, Volume 1: General Provisions 194. Washington State DOT, Olympia.

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TRB's National Cooperative Highway Research Program (NCHRP) Research Report 884: Guidelines for Managing Geotechnical Risks in Design–Build Projects provides guidelines for the implementation of geotechnical risk management measures for design–build project delivery. The guidelines provide five strategies for aligning a transportation agency and its design–builder’s perception of geotechnical risk as well as 25 geotechnical risk management tools that can be used to implement the strategies on typical design–build projects. This report helps to identify and evaluate opportunities to measurably reduce the levels of geotechnical uncertainty before contract award, as well as equitably distribute the remaining risk between the parties during contract execution so that there is a positive impact on project cost and schedule.

In addition to the guidelines, the report is accompanied by an excel spreadsheet called the Geotechnical Risk Management Plan Template. NCHRP Web-Only Document 247: Managing Geotechnical Risks in Design–Build Projects documents the research effort to produce NCHRP Research Report 884.

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