Questions and Answers Received Against 191BWC21R0002.pdf

191BWC21R0002 Page 1 of 10

TRUNKLINE & IOI REHABILITATION PHASES 1-3

Questions and Answers Received Against 191BWC21R0002 – Trunkline & IOI Rehabilitation Phases 1-3

Q1: Per the Project Design & Specifications, 2.4, Sewer Manhole # 1A, Question is, “the location and depth are not realistically compatible with intended design usage. Will a Value Engineering (VE) recommendation get recognized or is this MH to be bid per design & spec’s?”

Re: Part 3, 3.1 – C - “All MH’s shall be constructed as indicated on the Contract Drawings.”

A1: Assuming reference to Spec Section 46.10.00, MH #1A shall be bid per the design and specifications. Value Engineering (VE) proposals may be considered only after award of a contract.

Q2: Per Project Solicitation, L.06, Technical Proposal Instructions, B. Technical Proposal, d. (b)

“Provide an organizational chart …” Question is, For readability can the organizational chart be an 11x17 and counted as 1 page as the project schedule is?

A2: Yes.

Q3: Per Project Solicitation, Construction Schedule, Section F – Deliveries or Performance, 52.211-

10 Commencement, Prosecution and Completion of Work; “… The entire project time frame provides for 960 calendar days, where Phase 1 & 2 are allotted 570 calendar days and Phase 3 is allotted 210 calendar days (if approved)…”. Question is, Are the phases anticipated to be under construction consecutively or concurrently?

A3: See Specification Section 01.11.00 1.6 B. Phases are to occur consecutively; Phase 1, then Phase 2, then Phase 3.

Q4: The requirements in Section 46.06.00 Carbon Fiber Composite Structural Manhole Rehabilitation

1.8 Qualifications appear to be unrealistic. I am a certified applicator for FYFE Company which was founded in 1988 and is a pioneer in the FRP structural strengthening industry with over 40 patents in the field and they do not have the 1,000 manholes of performance record required of the manufacture (1.8 A) after over 30 years in business.

If the manufacture cannot meet the requirement the applicator such as myself will not be able to meet the 100 manholes rehabilitation requirement using CFSMRS also.

Can the requirements be changed to being an approved applicator of a CFSMRS only? Or can a deviation be submitted to rehabilitate the CFSMRS manholes with a 100% epoxy system at 250 mils?

A4: Specification Section 46.06.00 1.8 A.1. has been revised to require the manufacturer to have a minimum proved performance record of 100 manholes.

Also, Specification Section 46.06.00 1.8 B.3. has been revised to require the applicator to have completed a minimum of 50 successful manhole rehabilitations using the CFSMRS.

No deviation to the CFSMRS design shall be allowed.

Q5: We have questions about the qualification requirements for the Installer and Project Manager in

Spec Section 46.04.00. It states (1) “The Installer must have successfully installed at least 1,000,000 linear feet of 30-inch to 42-inch diameter CIPP in wastewater collection systems”, and

191BWC21R0002 Page 2 of 10 also (2) “the installer’s Project Manager must have a minimum experience of five (5) projects having pipe 30 inches to 42 inches in diameter”. Can these requirements be modified by Addendum?

A5: Specification Section 46.04.00 1.8 B.2.c. has been revised to require the Installer to have successfully installed at least 250,000 feet of 30-inch and greater diameter CIPP in wastewater collection systems.

Also, Specification Section 46.04.00 1.8 B.3. has been revised to require the Installer’s project manager(s) to have a minimum experience of five (5) CIPP projects having pipe 30 inches and greater in diameter.

Q6: See pg. 51 of 65 - Revised Solicitation

Please clarify the two statements below regarding Original and Hardcopies:

• “An original and 3 hardcopies of the proposal (FOR A TOTAL OF 4 PROPOSALS” – copy/paste from

• G. Arrangement of Proposal. The proposal shall consist of physically separated volumes, individually entitled as stated below.

The required number of copies (hardcopies include original) for each volume is shown below:

Volume Title Hardcopies Electronic Copies

I Business Proposal 1 1 II Technical Proposal 4 4 III Pricing Proposal 4 4

A6: A total of 4 hardcopies of proposals (1 original and 3 copies) are required for each Volume II and Volume III and only one original hardcopy is required for the Volume I Business Proposal.

Provide the number of electronic copies indicated as well for each volume.

Q7: Would the project consider a CIPP liner that is an approved equal that meets or exceeds the project specifications but would alter the minimum design thickness? The composite liner (felt/fiberglass) is thinner and stronger and allows more competitive bids due to efficiencies with freight/weight of liner, and better productivity to install.

Additional follow-up information provided:

In regard to a prior question regarding an equal or expanded as specified CIPP, we respectfully request that USIBWC/Nogales consider our submittal of information regarding a reinforced CIPP liner system. The material is standard material as standardized and allowed in ASTM F1216. ASTM F1216 allows for and provides information regarding guidelines in fiber reinforcement and all materials. Your table 42 seems to allow for this as well with the 50-75% retention requirement range for long-term Flex Mod. A reinforced material is stronger but thinner and holds up to the specified 75% retention. With our request, we are also providing a sample design with an alternate min. thickness chart to be reviewed - Table 43 revised with new column of data.

Table 41 also allows for enhanced resins along with traditional neat resins. Can we request how USIBWC/Nogales came up with a minimum thickness table with clear variables in physical properties. If we’re tracking your design calculations properly the thicknesses are using lower values that drive thickness. Also, considering the variables stated in Table 41 and 42, we respectfully request the alternate submittal of information to be evaluated.

Potentially, requiring the minimum thicknesses be removed from the table and replaced with approved thickness design stamped by Arizona P.E.

191BWC21R0002 Page 3 of 10

A7: Yes, the project would consider a CIPP liner that is an approved equal that meets or exceeds the project specifications. However, the product information provided by the Offeror states that the maximum shot length for their specific product is 750 linear feet; thus, that product would not be acceptable for several of the pipe segments listed in Table 43 that have lengths ranging up to 1,265 linear feet. The Contractor shall be responsible for ensuring the final design of the liner proposed complies with all specifications and site specific requirements of the project.

The column titled "Min Liner Thickness (mm)" in Table 43 of the specifications has been deleted, as such there is no minimum required liner thickness. In addition, Specification Section 46.04.00

2.4 H. and Table 43 have been revised to clarify the table provides site specific design parameters for each pipe segment between manholes. See revisions in Specification Section 46.04.00.

Also note that all CIPP design documents and calculations including thickness are required to be signed and sealed by an Arizona P.E. per Specification Section 46.04.00 1.9 C.

Q8: Does the design table for CIPP for minimum thickness, does this reference the finished thickness or the nominal thickness for the CIPP design?

A8: Table 43 referenced the minimum required thickness of the finished liner to be used for bidding purposes only. However, the column titled "Min Liner Thickness (mm)" in Table 43 has been deleted, as such there is no minimum required liner thickness.

Q9: in Phase 1…

MH 6A two lines appear to come in at this MH. Does the district have flow rates at these MH’s?

A9: MH6A and 16 are within Phase 2. Reference Drawings II-GI-0004, Lateral Information Table.

There are no flow rates available for the laterals.

Q10: Are there existing pictures of MH 16 that show the drop locations?

A10: Not sure if meant pictures for MH16 or MH6A. There are no pictures.

Q11: In Phase 3… o Map page III-CU-2012, Reference to CIPP start on both MH 37 and 38. Can you clarify which MH the CIPP should start at?

A11: Phase III CIPP should start at MH#37. The III-CU-2012 profile has been corrected in the revised drawings. Also see Specification Section 01.11.00 1.5 A.3.

Q12: As an Arizona based, global infrastructure rehabilitation company specializing in carbon fiber reinforced polymer (CFRP) systems, we are interested in bidding (as a subcontractor) for the subject project in Nogales, Arizona.

We noticed that the specifications call for 1,000 manholes repaired by the bidder with CFRP among the criteria to qualify for the manhole rehabilitation part of the project. I would like to point out that although, infrastructure rehabilitation with CFRP has been carried out for decades, manhole rehab with the material is relatively a new application. This task is not more challenging than ~ 1,000 projects we have completed to date; nevertheless, we are not able to provide 1,000 repairs specifically conducted on manholes at this time. We suspect none of the FRP companies on the market will be able to meet this criterion resulting in a situation of receiving non-

191BWC21R0002 Page 4 of 10 competitive or no bids at all for this portion of the project. We request IBWC/Engineer of Record change this qualification to “minimum of 250 projects completed on concrete structures.”

A12: See response to Question 4 and revised Specification Section 46.06.00.

Q13: Nukote Coating Systems to internally rehabilitate pipe

Nukote has developed pipe rehabilitation solutions for steel or concrete pipes and culverts from 24” to 12’ diameter. Our SIPP (spray-in-place pipe) systems are delivered robotically and create a seamless liner which conforms to the substrate. Our semi-structural and full structural solutions are designed by in-house engineers to the specification of our clients to deliver the best results.

The advantages of our trenchless rehabilitation system are the following:

1. Minimal reduction in diameter, meaning less flow loss versus other options

2. Robotic capability can rehabilitate 24” and greater pipes with reaches up to 1,150’

3. Seamless installation applied to substrate does not require grouting

4. Capable of AWWA M28 Class III

5. 25-year, insurance-backed warranty and design life exceeding 50 years

6. Diameter changes in the pipe are seamless

7. Superior tensile strength (>3500 psi)

8. Long-term stability

9. Excellent abrasion resistance

10. Environmentally compliant with no chemical leaching

A13: No question provided. Variations or substitutions to the design will not be considered as part of the Solicitation process.

Q14: In Phase I, what is the available access to MH 94?

A14: Contractor would have to determine their own point(s) of access using established easements or they would have to establish their own with adjacent property owners. Reference Specification Sections 02.01.00 and 31.11.00 for requirements of clearing vegetation for access to the work.

Cutting or reshaping existing Potrero Creek banks will be considered on a case by case basis and all banks shall be repaired and restored to ensure no future erosion will occur. Existing dirt roads around the Creek may be used with written permission of the property owner and shall also be restored to preconstruction conditions once construction is completed.

Q15: The qualifications required for installer of Carbon Fiber manholes are not achievable related to the number of manholes rehabilitated. The qualification language pertains to other manhole lining system - the “Protective Lining System” in Bid Item 9 and 24. Please consider requiring the Carbon fiber installer to be a “CERTIFIED APPLICATOR” of the material(s) approved without the requirement of number of manholes completed.

A15: See response to Question 4 and revised Specification Section 46.06.00.

Q16: Could not locate where the Instructions to Bidders is located where it details how many copies and in what form (hard or soft) the bids will be accepted.

A16: Reference Solicitation document 191BWC21R0002 Section L.03 General Proposal Instructions.

Q17: Are prime bidders and/or subcontractors required to have an Arizona contractor license during the performance of this contract? If so, do the prime bidders and/or subcontractors need to possess the contractor license at the time of bid? If not required at the time of bid, please clarify at what

191BWC21R0002 Page 5 of 10 stage of the contract award and/or performance process the prime bidders and/or subcontractors will need to possess an AZ contractor license.

A17: Yes, both prime contractor and all subcontractors are required to have an Arizona contractor license. These are not required at the time of bid. Contractor licenses for all contractors would be required for submission at time of contract award.

Q18: For this RFB, are there any participation goals, requirements, and/or good faith efforts to obtain participation of any subcontracting firms of specific ownership designations, such as disadvantaged (DBE), small (SBE), minority-owned (MBE), woman-owned (WBE), or other similar firms?

A18: For this RFP (not RFB), reference FAR Clause 52.219-9 (included in the Solicitation). A Small Business Subcontracting Plan is required for submission and will be made a part of the resultant contract. Provide your plan within the Volume I Business Proposal as part of the additional information required by the Solicitation L.04 B.g. Additionally, the Solicitation Contract Clause 52.219-9 Alternate I has been revised to Alternate II.

Q19: In solicitation section L.06.B.g, the Technical Proposal Instructions are requiring the submission of Resource Information. It is difficult to interpret exactly what type of information and level of detail the IBWC is requesting in this section. Please provide an expanded explanation of the resource information that must be submitted and an example of what an acceptable resource information submittal would look like, thereby clarifying the level of task breakdown required and what is expected to be submitted to provide a basis for each estimate. Also, is this information only required for phases of work and/or tasks that the prime will self-perform, or is it required for all subcontractors as well? If it is also required for subcontractors, is that information also required to be submitted at the time of bid, or can resource information for subcontractors be submitted within a certain amount of time after the bid?

A19: Labor resources should include each category/classification of labor with estimated hours proposed for each task under each CLIN for each Phase. Equipment resources should include each category/type of equipment with estimated hours proposed for each task under each CLIN for each Phase. Material resources should include each category/type of material with estimated quantities proposed for each task under each CLIN for each Phase.

The information is required for all phases of work and/or tasks performed by the prime and subcontractors. Small subcontract items/tasks can be summarized but those tasks performed by team members considered to be major subcontractors (those performing over 15% of project value) should be provided to the same level of detail as the prime contractor. All information is required to be submitted together in the proposal by the RFP due date. No information will be accepted after the due date.

Q20: CIPP specification section 46.04.00-2.4.E-H specifies the requirements related to the thickness of the CIPP tube. Subsections E & F give minimum physical properties and design parameters to be used to calculate the required tube thickness in Tables 41 & 42, but subsection H gives a Table 43 of minimum liner thicknesses that does not seem to correlate to requirements of Table 42 of the other thickness performance requirements in the specification. Also there are several columns in Table 43 that seem to have either inaccurate information or information that directly contradicts Table 42. Why do some of the soil depth fields in Table 43 shown no value? Why do some of the external water head to invert values in Table 43 exceed the soil depth? When the live load in Table 43 shows N/A, does this supersede the requirement in Table 42 to apply H20 or E80 live

191BWC21R0002 Page 6 of 10 loading? What should the bidder do when the calculated design depth per Table 42 is less than the minimum thickness shown in Table 43?

A20: See response to Questions 7 and 8, and revised Specification Section 46.06.00. Section 46.04.00

2.6 C.1. and 3.5 A. have been revised to require CIPP field samples meet or exceed Table 41;

notes have been added to clarify information in Table 42 and Table 43; and, Paragraph 3.5 B. has been revised to comply with ASTM F1216.

The following clarifications have been provided regarding Table 42 and Table 43:

Soil depth fields for pipe segments between MH 1A and MH 16 in Table 43 show no values because the existing pipe is encased in concrete and located in a large rectangular covered concrete floodway. Thus, the pipe experiences no soil loads but only loading from high water levels.

The external water head to invert values exceed the soil depths for pipe segments between MH 16 and 32 because the existing pipe is located a few feet below an 18-foot high concrete lined open floodway. Thus, the pipe typically experiences from 2 to 5 feet of soil loads plus loading from high water levels when the floodway is assumed to be flowing full.

When live loads in Table 43 are shown as N/A, this means that the pipe is not subject to either H20 or E80 live loading. The intent of Table 42 is to show that when the pipe is subject to live loading by being under a roadway or railroad, then the calculations need to assume either H20 or E80, respectively, versus some other type of live loading.

Q21: Bid Item 14 calls out 400 LF of pipe repair. Where is the repair located? Is it multiple repairs? If so, where are they? What type of pipe material is required to complete the repair?

A21: Bid Item (CLIN) 14 applies to pipe repairs of RCP for the CIPP installation. Repair locations are unknown, and there may be multiple repairs. Actual quantity for this Bid Item is unknown.

Reference Specification Section 33.05.39.41 Reinforced Concrete Pipe for pipe requirements and specifically Subsection 1.6 for applicable measurement and payment under this CLIN. Note that Section 46.04.00 3.1 F.2. indicates when a point pipe repair may be needed.

Q22: On sheet reference number I-CU-2043 of Phase I, there is a note 2 pertaining to a 12” Rio Rico forcemain which connects to the NOI at MH #96 (Sta. 450+73.53). The note states the contractor is responsible for all work required to bypass flows from the forcemain. However, there is no information provided on this forcemain to be able to design a competent bypass plan for these flows. Can further information associated with this 12” Rio Rico forcemain be provided? (i.e.

flow data, anticipated bypass suction manhole location, distance or total length of the existing forcemain from MH #96 to the pump station, frequency levels of the forcemain in operation, etc.). Further information is required in order to successfully quantity this item in the bypass scope of work for the bid.

A22: The sewer line from Rio Rico consists of an 8" forcemain that ends at a manhole (serving as a meter station) upstream of the IOI MH#96 and is owned by Liberty Utilities. Design drawings from Liberty Utilities indicate the 8" forcemain transitions to a 12" forcemain, but this does appear to be what was built. Liberty Utilities has indicated the forcemain should be an 8" line up to the manhole (meter station). At this manhole the ownership changes to the City of Nogales (CON). There is some type of open flow meter inside the manhole and downstream the sewer line becomes a 12" PVC gravity main line that connects to the IOI at MH#96. There is an additional intermediate manhole located between the manhole (meter station) and the IOI manhole. Liberty Utilities noted that at some point there was a holding tank installed at this intermediate manhole, 191BWC21R0002 Page 7 of 10 but they do not know if the holding tank is still in place or was removed. There are no other sewer lines contributing to the 12" main.

A point of contact for Liberty Utilities has been provided in Specification Section 00.31.50. The CON point of contact is Alejandro Barcenas and contact information is already included in the Section 00.31.50. See revisions to the drawing I-CU-2043. Liberty Utilities has also provided their design drawings for the forcemain and 12" line; see attachment with the recent amendment including the design drawings and photos.

The design of the bypass system is the responsibility of the Contractor including determining location and means/methods of bypass suction. Contractor should field verify all existing sewer lines and inspect the manholes mentioned above to determine if these could serve for bypassing.

All bypassing of the Rio Rico sewer line and requested shutdowns of the lift station and forcemain require coordination with and approval from Liberty Utilities and the City of Nogales.

Liberty Utilities provided the following information for their forcemain:

Average flows are approximately 0.391 MGD, with a peak flow of 0.449 MGD. The flow is fairly constant but lessens overnight.

The forcemain lift station capacity is approximately 2.5 hours; this is the maximum duration the lift station and forcemain can be shutdown.

Q23: Reaching out to offer a product presentation on Mechanical Splicing for Reinforcing Bar; aka

Rebar Splicing or Coupling. This is a great opportunity to learn more about the advantages and applications for using mechanical splicing and end anchoring. The presentation is geared toward structural engineers and specifiers that utilize reinforcing bar when designing concrete structures.

A23: No question asked. ACI always allows mechanical splicing. Means and methods for reinforcing are up to the Contractor and will be reviewed as part of the submittals after award.

Q24: Specification Sec.# 46.04.00-1.8-B Cured-In-Place Pipe (CIPP) CIPP Installer Qualifications

Per 1.8-B-2c of the CIPP Specifications, the Installer must have successfully installed at least 1,000,000 linear feet of 30” to 42” diameter CIPP in wastewater collection systems. To provide full and open competition, we are requesting that the linear footage requirements in 1.8-B-2c for the CIPP Installer be relaxed. Per the Solicitation on page 1 of 65, this project is Solicited Full and Open Competition. There may possibly be only 1 installer that meets the installer qualifications. The minimum proved performance record for the CIPP Product of 250,000 linear feet of successful 30”-42” diameter CIPP installation in the U.S as specified per 1.8-B-1a of the CIPP Specifications.

A24: See response to Question 5 and revised Specification Section 46.04.00.

Q25: Tech Specification 01.32.33 Photographic Documentation Part 3.1 Preconstruction Video and Photographs

As a safety measure to record the Limits of Disturbance including the bypass alignment along private and public surface restoration, is it possible to fly a camera mounted drone the length of the pipeline route at approximately 200 feet parallel to the Union Pacific Railroad tracks at approximately 300 feet above ground before starting construction activities?

191BWC21R0002 Page 8 of 10

A25: Recording of site conditions by any means and methods for the Contractor's convenience or safety is acceptable. Ensure to comply with any "drone or unmanned aircraft" federal, state, and local laws and regulations.

Q26: Solicitation Section H.10 Contract Work Schedule Additional Inspection Forces over 40 hours per week.

If the Contractor requests to the COR to work more than 40 hours per week, and the request is approved, then Contract is required to pay for any overtime inspection costs by the Government.

What is the overtime rate that will be charge?

A26: These rates are not yet finalized. The OT rates per day and per hour are for the Construction Inspector under the Construction Management Contractor to be selected. Examples of past rates on USIBWC projects are listed below per year. Rates vary per Contract. The actual rates will be provided to the Construction Contractor after award of the CM Contractor.

2015 - $166/hr and $1,328/day (8-hrs) 2016 - $160/hr and $1,452/day (8-hrs) 2017 - $155/hr and $1,239/day (8-hrs) 2018 - $171/hr and $1,615/day (8-hrs)

Q27: Spec. 00.31.19 Existing Condition Information Pertinent Site Information: Monsoon Season

Part 7 of Pertinent Site Information in Contract Clause 52.236-4 states that no work will be performed within the tunnel or waterways during the monsoon season. Based on the monthly weather conditions from Nogales, AZ, the maximum monthly precipitation falls in July and August. Are these two months considered as the monsoon season? Please clarify if the season is just these two months or if it is considered longer for this project.

A27: July and August are part of the monsoon season. Reference Specification Section 01.11.00 Paragraph 1.6 D. describing the typical monsoon season. Note that the source of stormwater within the tunnel and waterways includes precipitation from storms to the south in Mexico. The link included in Specification Section 00.31.19 1.8 B. includes historical flows in the Nogales Wash from a USGS station.

Q28: Contract Clause 52.229-3 Arizona Sales Tax Please clarify if Arizona State Sales Tax is applicable to this contract?

A28: Contractors need to determine what taxes are applicable to the project and per FAR Clause

52.229-3, all taxes need to be included in your bid.

Q29: L.06, Page 58 of Solicitation Line Item g Resource Information

What will be an acceptable Numerical System to employ by the contractor to aid the Commission to track the breakdown of each task?

A29: The Contractor may use any numerical system they prefer to breakdown the categories for each subitem under each task or phase, but they should each be broken down under their applicable CLIN No.

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Q30: 46.04.00 Cured-in-Place Pipe 1.8-B-4 Product and Manufacturer/Installer Qualification Requirements – ISO 9000

Is it a requirement of this project that the CIPP Installer seeking compliance confirmation operate under a quality management system which is third-party certified to ISO 9000 or other recognized organization standard to be deemed Commercially Acceptable? Typically for CIPP project the Product and Manufacture are required to be ISO 9000 Certified, not the installer. CIPP samples will be prepared in the field for each installation and the pipe physical properties will be tested in accordance with the specifications by a third-party ISO 9000 Testing Facility. Please clarify.

A30: Specification Section 46.04.00 1.8 B.4 has been revised. The installer is not required to operate under a quality management system which is third-party certified to ISO 9000.

Q31: Tech Specification 00.31.19 Existing Condition Information CCTV Inspection Videos of Pipeline and Manholes

Does IBWC have CCTV Inspections of the existing pipeline and manholes for this project which can be provided for contractors use in determining the pre-construction conditions of the sewer system and properly pricing of this proposal?

A31: Yes, there are some CCTV videos available and attached with the recent amendment. Also reference Solicitation attachment "B&C Evaluation of IOI Report 200503" for the evaluation of the entire IOI in 2005. From what has been observed over the years, the pipe conditions have continued to worsen.

Q32: L.01 Pre-Proposal Conference and Site Visit Conference Minutes and Attendee Sign In Sheets

On 2/23/21 a Pre-Proposal Conference and Site Visit took place for this Solicitation. Can the IBWC please provide the Agenda Presented, the Meeting Minutes and Attendee Sign In Sheets from the Conference and Site Visit?

A32: As stated during the Pre-Proposal Conference, the items discussed with the Contractors and the sign-in sheets would be provided with the next Solicitation amendment. See attached documents.

Q33: L.01 Pre-Proposal Conference and Site Visit Questions from the 2/23 Site Visit Field Observations

Is there truck access in the concrete floodway, and if so, is truck access permitted in the concrete floodway?

A33: There is one location for truck access into the concrete lined open floodway and the only access to the concrete covered floodway (tunnel) is near MH#13. There is an entrance to the open floodway just downstream of MH#24 off N. Morley Ave. The Contractor may investigate if there is access through the Potrero Creek to enter the concrete lining where it ends.

Vehicle and equipment access are permitted onto the open concrete floodway, but caution shall be taken not to damage the concrete lining along the Nogales Wash and take note of certain areas that are deteriorated. Any damage due to Contractor's operations and equipment shall require repair.

Q34: L.01 Pre-Proposal Conference and Site Visit

Do water levels in the concrete floodway only rise during rain events or do other factors influence water levels?

191BWC21R0002 Page 10 of 10

A34: No, as discussed during the Pre-Proposal Conference several factors contribute to the water levels in the concrete floodway. Note that the source of stormwater within the tunnel and waterways includes precipitation from storms to the south in Mexico and wastewater due to standard practices in Mexico. Reference Specification Sections 00.31.19 1.8, 00.31.26, and 02.02.00 and the amendment attachment "Pre-Proposal Conference Key Points to Contractors" for more details.

Q35: L.01 Pre-Proposal Conference and Site Visit

Are multiple lining crews permitted to work on construction phases 1, 2 (and 3 if awarded) simultaneously?

A35: The Contractor is permitted to schedule multiple lining crews, if preferred, to work simultaneously within the same Phase. Reference Specification Section 01.11.00 1.6 B. which requires that the phases occur consecutively; Phase 1, then Phase 2, then Phase 3 (if awarded).

Note that current phasing restrictions are due to the NADB laterals project that is in progress and must be completed before the CIPP installation may occur in that Phase. If the NADB laterals project is completed and the CIPP installation work will not interfere with any other stakeholder's project, the Phases may be released to be completed concurrently at the Government's discretion.

Q36: L.01 Pre-Proposal Conference and Site Visit

Do MHs 1 – 13 at street level that are fused shut match up with the opening for these manholes in the tunnel?

A36: Yes, for Manholes #1-12. Manhole #13 is not located within the covered floodway. See Solicitation attachment "Nogales Project As-Builts 19710501" which show the original construction of the upper access manhole cover through the tunnel for the Trunkline manholes within the tunnel.

Q37: L.01 Pre-Proposal Conference and Site Visit

Was the Pre-Proposal Conference and Site Visit Mandatory as there is a Statement of Attendance at Pre-Bid Conference and Site Visit that must be submitted with the Proposal.

A37: Attendance was not mandatory. The statement required in IBWC Form 117 is only for record.

Q38: Based on the number of RFI questions submitted previously and the questions being submitted currently which need to be answered in order to produce a compliant submission for this Solicitation, is it possible to extend the submission date for by at least 3 weeks to Monday, April 19th, 2021. Please note, this will be dependent on the responses provided by USIBWC.

A38: The proposal due date has been revised to 3:00 PM MDT on April 14, 2021. A second review of questions will be allowed. Submit any additional written questions to the Contracting Officer by 12:00 PM MDT on March 25, 2021.