QnA 10.14.2020.pdf

Questions and Answers during Advertisement for

CO FLAP US50(1) Little Blue Creek Canyon

September 17, 2020

Questions Answers

1 Are there electronic CAD files for the project that can be made available to contractors? Having the electronic files increases the efficiency and accuracy of our earthwork take-offs.

No, electronic CAD files will not be provided.

2 The Ditch Armoring at STA. 614+25 – 614+80 LT is not shown on the cross sections. Will cross sections be provided showing the

Ditch Armoring at STA 614+25 – 614+80 LT.? If yes, please provide.

Armoring is not shown in sections. Armoring to be field fitted to meet the existing slope, and fit within the criteria shown on the sheet. Cross Sections showing the armoring will not be provided.

3 The Bank Stabilization at STA 615+80 to 616+10 LT is not shown on the cross sections. Will cross sections be provided showing the bank stabilization at STA 615+80 to 616+10 LT? If yes, please provide.

Stabilization is not shown in sections. Armoring to be field fitted to meet the existing slope, and fit within the criteria shown on the sheet. Cross

Sections showing the armoring not to be provided.

4 Will the FHWA consider changing the Mumble strips (sinusoidal) specification to a standard CDOT rumble strip detail?

No, bid the project using mumble strips.

5 To install the Riprap per the cross sections and typical section(s) on sheets G2-G3, excavation and backfill will be required. Please confirm the excavated quantities will be paid under 20401-0000

Roadway Excavation.

Excavation required to place the stream armoring is incidental to the pay item. Excavation material generated is shown under Available Material in the grading summary.

Refer to the SCR’s and the FP-14 for work considered incidental.

Excavation for these quantities is not measured for payment and not paid for under the 20401-000, Roadway Excavation Item.

September 23, 2020

6 Will bids be accepted for alternate pipe materials for the culverts/drainage? I would propose corrugated HDPE pipe which meets CDOT requirements.

No, but a value engineering proposal may be considered after contract award.

7 Does FHWA require the assistance of a blasting consultant for approval of contractor submittals? Not at this time.

8 The geotechnical report references two reports that were done by YA and Associates.

Will the FHWA provide these reports? The Geotechnical report indicates that the YA reports should be referenced while reading the Geotechnical Reports. The actual bore logs are needed to evaluate the temporary shoring for the retaining walls and to design the support of excavation required for the

Rockery Walls and the GRS walls. In Table 2 “Summary of the YA Borings

Performed within the current CO US50(1) Alignment” no elevations are given , which requires inaccurate scaling from cross-sections to determine the rock elevation for the 12 bores that were taken for the retaining wall. In addition, It’s necessary to make a determination of the quality of the in-situ material above the rock to assess the predicted “hang time” of the excavation to design the support of excavation required.

These reports will be uploaded to the solicitation.

9 Has the FHWA obtained the required approvals for the successful contractor to obtain construction water by pumping water from the Blue River

FHWA has not obtained water rights. The successful contractor will need to coordinate this on their behalf.

October 1, 2020

10 The section 262 GRS specifications require design in accordance with FHWA HRT-17-080. For walls less than 25 feet in height, should the reinforcement be placed to the cut slope starting at

0.5H at the bottom and increasing until an RL of 0.7H is achieved, as indicated in FHWA HRT-

17-080 Section 4.3.4.5 on Pages 32 and 33? Or, should the reinforcement be 0.5H for the entire wall height?

For proposed wall heights of less than 25 vertical feet, a reinforcement length of 0.5H is the minimum required. For wall heights equal to or greater than 25 ft. a 0.7H factor is required.

11 From section 107.11, How many stocked fire boxes will be required? The number of fire boxes and equipment may vary depending upon the time of year, activities being performed, orders/regulations in place by parties listed in SCR107.11. It is the responsibility of the Contractor to determine the number of boxes required to satisfy these requirements. Submit proposed boxes and locations for approval, and update as required.

12 From section 108.04 ADDED- Interim Completion Date states, “No day closures will be allowed after July 31, 2021 in this area”, does that require that all contract bid items from Sta.

587+00 to Sta.617+00 must be 100% complete prior to July 31, 2021?

The July 17, 2021 – Interim Completion

Date Incentive does not require that all contract bid items from Sta. 587+00 –

617+00 be completed prior to or on July 31, 2021. All work that requires daytime full closures is considered work that may not be performed during nighttime operations, or work that cannot be performed without delaying traffic beyond allowable limits.

October 2, 2020

13 The IFB, section 205.08(b) states "offset lifts up to 18" horizontally to allow for drill equipment clearance". Additionally, section 205.08 ( e) states "When the cut height will require more than one lift, maximum 18" offset between lifts is permitted to allow for drill equipment clearance". Since these two statements allow for overbreak up to 18", will the allowed overbreak be included in the quantity of rock excavation for measurement and payment?

See FP-14 204.16(a)(2)(b): Do not include over breakage from the backslope in rock excavation.

14 The IFB section 157.09 (b) states prior to beginning in-stream work, submit a temporary stream diversion plan (for) approval. Submit a diversion plan that addresses the following at a minimum: (a ) Constructing a diversion that can accommodate 350 CFS without encroaching within the limits of construction; (b)devices proposed for use and; (c) Proposed methods of installation, maintenance and removal." In the areas that require work in-stream work, specifically the Special Rock Embankment stream bank protection in the vicinity of 588+00 and

600+00 the stream channel is not large and it does not appear to be feasible to pass flows of 350

CFS without encroaching within the limits of construction. Please clarify this requirement.

FHWA believes this CFS requirement to be feasible. The approved means and methods must remain within the limits of construction shown, but should be outside the limits of the work being performed.

15 Are sealed bids allowed to be submitted in-person at the FHWA Central Federal Lands Division

Office, 12300 W. Dakota Avenue, Lakewood, CO 80228?

Yes

16 On page ITB page E-13, Section 108.01 (f) states “from October 16 to April 15, US 50 must be opened to two-way traffic during nighttime without delays. Coordinate with the CO for effective dates”. On ITB page E-37, Section 156.07 (1) states “from October 16 to April 1, US 50 must be opened to two-way traffic during nighttime without delays if winter weather is expected on

Yes, closures may be permitted provided

CO-92 is open, no winter weather is expected, coordinate nighttime closures for approval beyond the ranges shown and for

C-92 route. CO-92 is not plowed by CDOT during the night. Coordinate with the CO for effective dates”. Can we assume that nighttime closures are allowed after October 16 as long as

CO-92 is open and there is not winter weather?

effective dates of required openings with the

CO.

17 ITB page E-27 indicates the 4th paragraph from the bottom of the subsection should be deleted and substituted with “Reestablish missing control points and stakes before slope staking begins”.

We are not clear who has the responsibility to reestablish the missing control points.

Additionally there appears to be numerous monuments on the existing roadway that will be within the construction limits. While it may be possible to preserve some of these during construction, it will not be possible to preserve others. Who the responsibility to relocate these monuments?

Question 1: The revised language between the FP-14/ SCR’s reads: Preserve initial reference and control points. “Notify the CO of missing control points or stakes at least 10 days before beginning construction.

Reestablish missing control points and stakes before slope staking begins.”

Question 2: Refer to FP-14 107.02 for more information.

18 In the Federal proposal it suggests the former CDOT yard on US 50 could be used for this project. If this is possible, can you inform me as to what utilities are available at that site. I am planning a site visit later this week and wanted to make arrangements to view the site.

See SCR 105.04: Former CDOT yard, phone and electric hook-ups at pads may be available.

19 For the GRS segmental wall, the GRS Wall Backfill quantities on surrmary schedule A of

26,929 CY do not include the 3’ reinforced zone that is required to go back to the C/L of road as shown on special drawing 262-A. Can you verify that this reinforcing zone and the extra material not included in the retaining wall summary of quantities are required to support guardrail impact loading on the wall?

The reinforcing zone is not required for guardrail purposes.

20 The Wall summary also shows a small amount of wall backfill 1,217 CY that is not part of the reinforced zone. This quantity does not appear to be near enough to provide a 1:1 backfill zone as shown on drawing 262-A and will only cover a small amount of backfill at the front face of wall. There is no bid item for soil nail wall shoring, that would be required to avoid a 1:1 backfill zone behind the reinforced zone. MSE-4 boring shows weathered rock down 22.5’ or solid rock at 26’. Will a shoring pay item be added to allow walls to be installed as shown on cross sections? If no pay item is added, will contractor be responsible for temp shoring, or additional 1:1 slope back material plus required temp widening’s to get traffic around MSE Wall excavations?

Question 1: No shoring item will be added to the Contract. Refer to Answer to Q2 below.

Question 2: Contractor is responsible for excavation and backfill. Sheet G16, Note 5:

Slope or shore excavation according to

Section 208. See Section 156 for Public

Traffic Requirements. Refer to Sections 208, 209, 257 and 262 of the FP-14 and the

Special Contract Requirements.

21 Do we need to hold off the wall design until the final survey by the contractor is done and the updated TOW and BOW lines for each wall are developed by a contractor’s civil engineer? Or, we can move forward with the wall design based of the wall profiles provided on the project plans Sheets G10 through G17? This could have a major impact to both the schedule and costs.

Question 1: Retaining wall design should be performed after surveying. Refer to Section

257 of the SCR’s.

Question 2: Contractor is responsible for the retaining wall design. 25701-0000, Contractor Furnished Geosynthetic

Reinforced Soil (GRS) Retaining Wall

Design. Refer to Sections 257 and 262 of the

SCR’s.

October 7, 2020

22 Will the owner consider a 2-3 week time extension on the bid due date to allow contractor more time to analyze cost of quantities not captured in summaries and to further develop the best approach to critical blasting and wall construction activities?

No, the bid opening date will not be extended at this time.

23 In the Final Geotechnical Report dated 6/1/2020, Table 6 indicates that the foundation soils for the GRS Retaining Walls will be either Sandy-Gravels/Cobbles/Boulders or Sandy/Silty-

Gravels/Cobbles/Boulders. This table indicates that the GRS Wall will be in those two types of material and there is no indication that rock will not be encountered. Since we have to rely on the information provided and there is no indication of rock formations in the GRS excavations, will the FHWA consider this a Changed Condition if rock is encountered?

No differing site condition will result if bedrock is found in wall excavations. Refer to the Geotechnical report, Subsection 5.2

Excavations. See Note 10 on sheet 262-A. If bedrock is encountered when excavating for

GRS wall construction, submit an RFI with a proposed change in wall design.

24 The GRS Retaining Walls in some cases require the reinforcement zone to extend 3’ beyond centerline of the reconstructed roadway as shown on the Typical Section GRS Wall on sheet

G16 of the plans. In some cases this will require the roadway ditch to be temporarily filled with embankment, aggregate base and asphalt in order to accommodate the 24’ travel lanes requirement on weekends and the paved surface requirement in the two locations the ITB, section 156.05 (b). Please confirm that this is FHWA’s intent.

Contractor may use available width, including roadway ditches, to accommodate two-way traffic during the weekends.

25 IFB, page E-17, Section 107.01 references Section 404 and Section 401 permits. Will the

FHWA provide copies of these permits and any application documents that were required to obtain the permits. If we are to comply with the terms and conditions of these permits we need to have copies of the permits and the permit application documents so we are aware of all the requirements.

FHWA will provide 404 nationwide permit verification letter from USACE and applicable enclosures.

401 water quality certifications for nationwide permits are certified by statute in the state of CO without and further conditions.

26 Will the GRS design be based on 25-foot cross sections from the Contractor’s Final Survey as indicated in Section 4.2.1 of the FHWA Final Geotechnical Report (Report No. CO-CX-0050-

20-01), or will the design be based off of the 10-foot cross sections in the bid documents?

Refer to Section 257 of the SCR’s for design requirements.

27 Will you please confirm that other than the Field Lab required in Section 154, Contractor

Sampling and Testing, of the IFB, which will be used by the Contractors QC staff, no other field facilities are required to be furnished by the Contractor for use by the FHWA.

Confirmed

28 Will you please confirm that the Small Business Subcontracting Plan is to be submitted only after the apparent low bidder is announced and that no other Small Business percentage goals form is required to be submitted with the bid proposal.

A Small Business Subcontracting Plan is to be submitted to the CO by the apparent successful low bidder within 7 days of the bid opening and when requested.

No other forms for Small Business percentage goals are required to be submitted with the bid proposal.

29 Project specification 720.03 (a) refers to the segmental retaining wall units.

This specification is consistent with information published in 2018 Design and Construction

Guidelines for Geosynthetic Reinforced Soil Abutments and Integrated Bridge Systems Design

Manual (FHWA HRT-17-080 ). Specifically, it appears to reference table 5 on page 17 of

FHWA HRT-17-080, Units Not Exposed to De-icing Salts Zone 3. In addition to the information listed in the project specification, this table also states the following would meet the durability criteria with regards to Freeze-Thaw: “Less than one percent weight loss after 100 cycles for 5 of 5 specimens.”

Assuming the block meets all other listed project specifications, will it be acceptable for a test result that passes the above-mentioned criteria in a 100-cycle freeze-thaw test?

Question is unclear, please clarify. Submit wall materials that conform to the materials specifications of the contract.

30 Will Welded-Wire-Fabric basket facing be allowed for the GRS walls?

No. Facing for GRS walls is either

Segmental Retaining Wall Units (SRWU) or precast concrete panels.

31 Can a typical MSE wall, rather than GRS, be utilized?

Please define a typical MSE wall.

GRS walls are required in the contract. A

Value Engineering proposal for MSE walls may be proposed after award.

32 Is a concrete footing / leveling pad mandatory or can a crushed stone leveling pad be utilized?

Concrete footing is preferred. If other alternatives are available according to the wall design and manufacturers recommendations, they may be evaluated.

Refer to Special 262-A in the plans and

Section 257 and 262 of the SCR’s.

33 Is the Special Provision 262 (GRS Retaining Wall) to be utilized in conjunction with Special

Provision 257 (Contractor-Designed Retaining Walls) and Standard Specification 255

(Mechanically-Stabilized Earth Walls)?

SCR 257 and 262 are used for design and construction of GRS Retaining Walls.

Section 255 of the FP-14 is not applicable toward the design and construction of GRS

Retaining Walls.

34 What is the anticipated start date of this project?

A Notice to Proceed will be issued after award and upon acceptable Performance and

Payment bonds are received by the

Government.

35 The Reinforcement Layout Table on Sheet G16 indicates reinforcement length B=70% H for

H>25’ and B=50% H for H<25’. Section 4.3.4.5 of the “Design and Construction Guidelines for

GRS-IBS” FHWA-HRT-17-080, 2018, indicates “Once the base length of the reinforcement is chosen, the reinforcement schedule should follow the cut slope, if applicable, up to a B/H of

0.7.” and it is illustrated in Figure 20 on Page 33 of the 2018 Guidelines. For H<25’, for instance H=20’, the B at the bottom of wall will be 0.5H=10’. In the lower portion of the wall, should B be gradually increased from 10’ following the cut slope or shoring until B=0.7H=14’ is achieved in accordance with the 2018 Guidelines and remain B=14’ from there up to the top, or the B should be a uniform 10’ from the bottom to the top of the wall per the Reinforcement

Layout Table on Sheet G16?

The reinforcement is to remain constant from top to bottom.

36 Specification 205.10 (b).(10). requires a post-blast condition survey to be included in postblast vibration and airblast report for each blast. Can this be changed such that post-blast surveys are to be completed after blasting has been concluded for the entire project and not after each blast?

Post-blast surveys for residential structures will depend on homeowner’s availability and need to be scheduled in advance.

No change in specification.

37 Specification 205.06 (a). states the maximum peak particle velocity (PPV) of green concrete/shotcrete/grout greater than 28 days to be 2.0 inches per second (in/s). Research by

Lewis Oriard and others recommend safe vibration thresholds for concrete or shotcrete up to 12-

20 in/s. A conservative safe limit used in the industry when blasting near fully cured concrete is

8 in/s. Please consider revising the requirement to allow a maximum PPV limit for concrete/shotcrete/grout older than 28 days of 8 in/s and maintaining the reduction factors for cure times of 0-3 days: 0.125 x 8 = 1 in/s and 3-28 days: 0.5 x 8 = 4 in/s.

No change in specification.

38 For the Temporary Traffic Control, Wall Barrier and Crash Cushions, the bid quantities are

6,000 LF and 4 Each, respectively. There is no tabulation of the location(s) these items are to be

The Tabulation table for Temporary Traffic

Control, Sheet 21 of the plans, shows proposed quantities for the route. Locations used on the project. It appears that more quantity of these items will be required to build the project. If these items overrun will FHWA pay for the overrun?

for the items referenced is based on the approved traffic control plan. Quantities measured for payment are based on the;

approved traffic control plan, quantity used in the field.

October 13, 2020

39 Related to special drawing sheet G17 There is a 3’ zone of additional reinforcement that goes back to the C/L of the road or 3’ beyond the normal wall reinforced backfill zone. This zone appears to be missing in the quantities that make up the 26,929 CY of GRS backfill, and 8,725

CY of wall excavation. Please verify 1st that the zone shown below in yellow is required?

Second, that it is an additional quantity of GRS wall backfill, or structure excavation that is not in the wall summary quantities table?

Question 1: Yes, yellow highlighted shape of reinforcement is required.

Question 2: Correct, this is an additional quantity of GRS wall backfill, Structure

Excavation, etc.. that is not shown in the

GRS wall summary tables.

40 If a solid rock face is encountered when excavating for the GRS wall reinforcement length (0.5 or 0.7 of wall height) will the contractor be allowed to leave the rock in place or will it need to be removed to achieve the full reinforcement length?

Submit proposed wall design solutions for instances such as this. Proposals will be evaluated on a case by case situation.

41 In the event of a full closure of I-70 between Glenwood Springs and Vail that would require an immediate opening of (a minimum) one lane of alternating traffic will there be traffic que wait time restrictions enforced?

Yes, limit wait times to alternating one-way traffic, 30 minute delays.

42 Can the BLM lands adjacent to the project be used to access the top of cut slopes? Have any adjacent private land owners indicated a willingness to allow access?

Please define adjacent?

BLM lands may be available to access the top of proposed cut slopes. Contact the BLM for more information.

Contact private land owners for willingness to allow access.

It is the contractor’s responsibility to secure environmental clearances for access points outside the project limits.

43 The Invitation to Bid Solicitation Provisions contains multiple FAR declarations, representations, and/or certifications (i.e. Page B-13, B-14, B-20, B-24, and C-7), not asked to be submitted with the Offeror’s Bid Package on page A-i of the solicitation. Please confirm whether or not these additional pages are required as part of the Bid Package to be considered

Responsive

No, many of the representations made under the identified provisions and clauses are already included under the bidders System for Award Management (SAM) profile. Any that are not included in SAM will be viewed as a matter of responsibility, not responsiveness. However, please note that all bidders must be registered in SAM prior to submission of a bid in response to the solicitation, as identified on page A-ii.

44 SCR 107.02 indicates Century Link is in conflict with the project and REQUIRING relocation by OTHERS BEFORE construction. Please confirm whether this will take place prior to construction starting in 2021, or anticipated to be concurrent with the Offeror’s work

Century Link line is currently being relocated. Anticipated to be relocated before spring of 2021.

45 SCR 563/SCR 725.18 Weathering Agent – Please confirm all surfaces on the project that will require a Weathering Agent. SCR 725.18 indicates a “weathering agent that colors rock, cementitious, and galvanized surfaces to a brownish earth tone, and contains no pigments.

……”. In addition, please confirm which pay item(s) the Weathering Agent may be incidental to.

Not all surfaces on the project receive an application of weathering agent. Refer to the plans and SCR’s for references to

Weathering Agent. Item(s) that incorporate a weathering agent:

61901-0000, Fence (Steel Snow Fence)

46 SCR 635 has provisions for a Government Furnished Uniformed Traffic Control, Police Officer

(UTC), yet also indicates that the UTC will not be measured for payment. Please confirm that all necessary UTC hours and associated costs (including overtime) will be the responsibility of the Government.

The Gov’t will provide UTC for Contractor

Use. Coordinate with the CO the schedule, hours of operation, location and requested needs from the UTC.

It is anticipated that UTC may be used when needed, primarily during the allowable day closures timeframe.

47 Plans, Page B9 & B10, do not indicate an adequate quantity of Topsoil to place 3IN on all slopes

1:1 or flatter. Will the Offeror be required to import the balance of the topsoil (including the necessary yardage required to make up anticipated shrink) if the project does not contain sufficient quantities?

Not all slopes that are 1:1 or flatter are proposed to receive topsoil. Refer to the

Topsoil Summary for station ranges that are scheduled to receive topsoil. Additional topsoil may be available in select locations.

48 For the GRS Walls there are bores from geotechnical reports located in walls 2 and 3. Bore

MSE-6 indicates that there will be a good amount of rock excavation required to install the walls at this location. What amount of rock excavation should be assumed at walls 1, 4, and 5 where there is no boring information?

Borings are located throughout alignment.

See YEH 2010 and 2020. The contractor is responsible for assuming rock excavation amounts based on the contractor’s interpretation of the provided data.

49 Retaining Wall Summary Schedule B shows 8,725 CY of Wall Structure Excavation. Without any back slope or additional excavation we are getting a quantity that is double the summary using average end area from the cross sections. Please verify if wall structure excavation quantity is correct? Example of area from cross sections used in developing the structure excavation without any slope back. [See below picture]

The Government is currently reviewing structure excavation quantities. Revisions are anticipated to the Grading and GRS wall

Summaries. Amendment A002 will be published to make corrections and extend the bid opening date.

October 14, 2020

50 Is the wildlife friendly fence barbed wire or woven wire?

Refer to Special 619-A.

51 The IFB mentions 52.204-24 (Representation regarding certain telecommunications and video surveillance services or equipment) on page B-14, 52.209-13 (Violation of Arms Control

Treaties or Agreements) on page B19-20, and 52.223-22 (Public Disclosure of Greenhouse Gas

Emissions and Reduction Goals) on page B24. However, these items are not listed as needing to be turned in with the bid. Is it correct to leave them out of the bid envelope?

See response to question #43.

52 In the specs there is mention of weathering agents. Will this project require the guardrail to have a weathering agent?

The proposed steel snow fence will require a weathering agent.

53 Would a mixture of recycled asphalt and aggregate base be acceptable for 301 material? Recycled asphalt will not be permitted for use as 301 material