Attachment_1_Solicitation_Questions_and_Answers_Amendment_03.pdf

NAMA 216036 Roof and Portico

NAMA 216036 ‐ Restoration of Jefferson Memorial Roof and Portico

National Mall and Memorial Parks

Solicitation Questions and Answers

Note ‐ Questions 1‐7 were answered in Amendment 01, issued Tuesday, August 7, 2018.

Questions 8‐ 17 were answered in Amendment 02, issued Friday, August 10, 2018

Amendment 03:

18. Specification 01 50 00 notes that wood fencing is to be provided for the secure fencing around the secure space. There is usually a standard detail for temporary wood fencing that is installed on and around the national mall but it is not noted or detailed within the project documents.

Please provide wood fencing detail.

ANSWER: Refer to the NAMA Park Standard Fence Details sheet, attached. Note that for the contractor staging area wooden fence, please use the following approach in conjunction with the details:

1. Staging Area Fence: The fence around the staging area needs to be constructed as follows:

Fence to be 8 feet high solid wood fence.

1X4 or 1x6 boards in vertical position and installed between 4X4 posts every 8 feet.

The fence shall be painted light gray on exterior. (Submit color sample for approval by park.) The contractor shall maintain fence and trim/mow exterior and interior edges of fence.

19. Specification 01 50 00 3.2B specifies wastewater is to be removed from the site. Can it be filtered into a drain or does it need to be hauled away from site? Or is this a means and methods for the contractor?

ANSWER: Current requirement is for removal of wastewater from site, due to the potential of water, chemicals and other materials used in cleaning of the stone at the Memorial, per section

04 01 40.52. The means and methods will be the responsibility of the offeror so as to be legally conducted, which may involve collection, containerization, and removal. However, offerors should confer with local regulatory agencies as to other possible methods that may be acceptable for discharge of wastewater as noted in specification section 01 31 00 – Project

Management & Coordination, 1.8 Permits, paragraph B, on required permit from DC DOEE, and as required for other temporary facilities and controls, per the following local agencies:

1. Department of Energy and Environment (DOEE), Stormwater Management.

a. DOEE ensures compliance with MS4 applicable to stormwater.

b. DOEE regulation covers Environmental Protection Agency (EPA), Notice of Intent

(NOI) and National Pollutant Discharge Elimination System (NPDES)

2. DC Water and Sewer Authority Availability Certificate.

a. Includes temporary utilities hookup for construction trailer, etc.

3. DC Water and Sewer Authority Temporary Discharge Authorization Permit, Construction trailer, Utilities hookup

a. See above for temporary water and sewer.

b. Coordinate with provider for electrical and internet.

c. See Spec 01 50 00, Temporary Facilities and Controls, for requirements.

20. Sheet AS1.1 notes that exterior grade plywood is to be painted. What type of paint should be used here?

ANSWER: Paint that meets the following for the duration of the project can be used at the exterior‐grade plywood:

a. Complies with all environmental regulations for exterior paint.

b. Matches the color of the existing building material it will cover and/or to which it will be adjacent.

c. Will not damage the existing building material.

21. The documents call for salvaging existing drains. Is it possible to replace all drains with new and cap and fill the existing ones in place?

ANSWER: Salvaged drains could be replaced with new roof drains. No drains are to be capped and filled.

22. Slides from Pre‐Bid conference and noted within the audible presentation noted 4 exhaust fans are to be provide but drawings only show 2. Please clarify quantity of exhaust fans within scope.

If it is 4 and not 2, please clarify where these are to be placed and fed from.

ANSWER: There are only 2 (two) exhaust fans required, per the drawings.

23. RFP calls for a Safety Manager to be named to the project. Can the Superintendent serve as the safety manager or does this position need to be a separate person?

ANSWER: For this project, the Safety Manager or Safety Supervisor needs to be a separate individual, as outlined in the evaluation factor for Key Personnel.

24. Note 3.3 on AD4.2 calls out for the concrete topping to be removed. Please advise on the thickness of the concrete topping to be removed.

ANSWER: The thickness of the concrete topping may vary between 2”‐ 4”. Condition to be field verified.

25. Regarding Evaluation Factor IV – Past Performance, please confirm that it is acceptable to include past completed PPQs or completed CPARS/PPIRS in lieu of requesting new PPQs from our past National Park Services client references.

ANSWER: It is up to the offerors to make the determination whether to include past completed

PPQ's as part of the Evaluation Factor IV submission. As stated in the Evaluation Factor IV ‐ Past

Performance, "The past performance of the offeror and/or its proposed subcontractors on projects similar in scope and complexity will be evaluated in the areas of quality, timeliness, subcontract plan execution, and business relations. Offerors demonstrating a higher level of successful past performance in the evaluated areas will be more favorably rated. In the case of an offeror without a record of relevant, recent past performance or for whom information on past performance is not available, the offeror will be evaluated neither favorably nor unfavorably."

26. In Subfactor 2B: Prior Experience, the solicitation states, “The realistic and relevant demonstrated ability and competence on projects of similar size and technical complexity and ability to complete custom security facilities and upgrades to one‐of‐ a‐ kind elevator system of the Offeror (general contractor) and Key Subcontractors will be evaluated.” Please confirm custom security facilities and elevator upgrades are not relevant to the scope of work for this project and therefore will not be evaluated in our proposals.

ANSWER: In Section M, C. Evaluation Factors, Evaluation Factor II – Key Personnel/Prior

Experience, Subfactor 2B: Prior Experience, in the solicitation should read, “The realistic and relevant demonstrated ability and competence on projects of similar size and technical complexity and ability to complete historical tile roofing system and key subcontractors will be evaluated. Proposals reflecting performance on similar highly visible properties, teams that have worked together in the past, and evidence of projects constructed at similarly restricted work sites will be more favorable rated.”

27. In the Proposal Submission Package, there is a document titled "Subcontractor Reference." This form is not mentioned in the solicitation document. Please confirm 1) that we are required to submit the Subcontractor Reference Form for each proposed subcontractor, 2) how many project references we are required to submit for each subcontractor, 3) if each subcontract project reference must be within the past five years, 4) that these project references do not count towards the five project limit under Evaluation Factor II, Subfactor 2b, and 5) if we should include the Subcontractor Reference Forms under Evaluation Factor II, Subfactor 2B in our proposal and that it counts toward the 60‐page limit.

ANSWER: “Subcontractor Reference” in the Proposal Submission Package is not required to be submitted. You may delete “Subcontractor Reference” in the Proposal Submission Package.

28. Reference the Contract Price Schedule, Option C ‐ Earthquake Repairs. Please confirm that the earthquake repairs consist solely and entirely of the joint repointing shown and quantified on

A3.1. That is, 33,800 SF of joint repointing for all marble roof elements between the top of the dome and the bottom of the architrave.

ANSWER: The earthquake repairs exclusively consist of repointing the joints in the marble from the top of the dome to the bottom of the architrave.

29. Please confirm that our complete CPM schedule counts as one page in our proposal even if it spans multiple pages to ensure readability?

ANSWER: Yes, the CPM schedule will count as one page in the proposal.

30. Under Evaluation Factor IV: Past Performance, may we submit CPARS in lieu of the requested

Past Performance Questionnaires in our proposal?

ANSWER: The offeror may submit CPARS in lieu of the requested Past performance

Questionnaire.

31. Reference Note 1.2 on AD2.1 ‐ "Remove and salvage all electrified bird deterrent at the portico and colonnade ceilings prior to the beginning of work". Please provide a description and bid quantity for this electrified bird deterrent system as it is not shown on the drawings and none was not seen during the site walk through. Does it exist?

ANSWER: The electrified bird deterrent is a set of thin‐gauge wires that run along the architrave at the interior of the colonnade ceiling on both sides as well as around the perimeter of the architrave at the interior of the portico ceilings. Confirm operability and extent of removal with

Park prior to the beginning work.

Image 1: Electrified bird deterrent at architrave at interior of colonnade ceiling.

32. Please confirm load limits for the Stylobate Steps, Stylobate Mall, and Terrace Mall for scaffolding, staging, and potential use as a work area. For example, the lower marble step appears to be held up with non‐continuous steel angles, creating a cantilevered marble step condition. Is this lower step strong enough to bear upon?

ANSWER: The government cannot confirm the actual load limits for the areas noted in the question, as they are not identified on the staging area plan, nor was a plan included with the question to clearly outline which areas are being considered. Staging and work areas cannot intrude onto the terrace steps area since this area is outside of the contractor staging limits and is accessed by the public. Specific work areas for scaffolding or short term staging can be submitted as part of the contractor’s proposed staging and work plan for review by the government as part of Division 1 submittals.

33. On AS1.1, there is temporary protection shown as a dashed line at a defined area of the Portico

Roof. On AD1.2, Note 7.1, states that the marble tile roofing is to be removed and salvaged

(Type 1). Please confirm whether the marble tile roofing is to be protected or removed.

ANSWER: The marble tile roofing is to be protected at all times while in situ if work is being performed at adjacent roof elements (including drum walls).

34. On AS1.1, Detail 2 notes that the 2x8 rafters with fiberboard padding are to be attached to stone. Please provide attachment method. It is our understanding that no fasteners are to be drilled into the marble.

ANSWER: As shown on AS1.1, there are to be no fasteners to secure the temporary protection to the marble. Temporary protection to be weighted with sandbags as detailed on AS1.1.

35. On AS1.1, Detail 2 notes that exterior grade plywood is to be used. Is this plywood to be fire‐ treated? Note that fire‐treated wood degrades quickly in UV light.

ANSWER: The exterior‐grade plywood does not need to be fire‐treated.

36. On AS1.1, Detail 2 notes that a layer of clear polyethylene is to be laid down prior to protection.

This layer will cause condensation against the marble surface, which will potentially cause more biological growth. Please confirm that polyethylene is to be used.

ANSWER: A protection layer must be used between the temporary protection and the building elements. Polyethylene sheeting can be used as shown or a substitute may be submitted for approval by the NPS.

37. On AS1.1, Detail 2 notes that fiberboard is to be used as a protective layer. Per the specifications, the only reference to fiberboard is a "D5834 Standard Guide for Source Reduction

Reuse, Recycling, and Disposal of Solid and Corrugated Fiberboard (Cardboard)". Please confirm what type of fiberboard is to be used.

ANSWER: Moisture‐resistant fiberboard or 2” rigid polystyrene insulation can be used at the temporary protection.

38. On AD1.1, Notes 6.1 and 7.5 reference items to be removed (wood and fabric covering and loose waterproofing). Please provide photos of these elements in order to qualify and quantify the amount of work required to complete this work. These areas were not accessible during the walk‐through.

ANSWER: See photos below:

Image 2: The waterproofing in the portico attic is the black substance in the above photo that has been applied to the interior faces of the brick walls at the east, west, and north walls of the portico. Where bricks are visible, the waterproofing has already flaked off.

Image 3: The orange arrow points to the wood and fabric covered “reflector” opening cover that currently exists in the portico attic at both sides of the barrel vault. Above it is the black waterproofing substance.

39. On AD1.4, Note 7.5 states that metal flashing is to be removed. The upper roof area was not accessible during the walk‐through. Please provide photos in order to qualify and quantify the scope.

ANSWER: On sheet AD1.4, note 7.6 indicates metal flashing is to be removed. See photo below.

Image 4: Metal flashing at shaft at upper roof.

40. On A8.3, Detail 5 notes that silicone compression seals are to be installed. The specification does not list any products. Please provide a list of acceptable products. Specification section 07 01

36.91, 2.4.B., states to "Use sealant as required to secure seals in place during reinstallation of the marble." There is no known sealant on the market that will adhere to silicone. Even silicone will not stick to silicone. Please provide sealant type.

ANSWER: Both of the joint sealants specified in Section 07 92 00 (Dow Corning 756 SMS Silicone

Building Sealant‐HP and the Dow Corning 795 Silicone Building Sealant) will adhere to silicone.

41. Specification Section 04 01 4052, 1.2.A.3, states to "Remove sealant and sealant residue." The drawings do not indicate where this scope of work is to occur. Please provide locations and/or quantities.

ANSWER: The sealant removal referred to in Specification Section 04 01 40.52, 1.2.A.3, relates to the sealant that is present underneath all of the rib caps on the portico roof, which will need to be removed as part of the stone cleaning process. Note that removal of sealant as part of preparation for pointing mortar joints and installing sealant is also required in Sections 04 05

13.91 and 07 92 00.

42. On S1.0, there are numerous references to the catwalks and wall openings that were not accessible during the walk‐through. Please provide photographs to help qualify and quantify the scope of work.

ANSWER: See photos below.

Image 5: Existing metal and concrete catwalk condition at the perimeter of the dome.

Image 6: Existing masonry wall opening from catwalk space around dome into space between colonnade ceiling and roof.

43. On AD2.2, note 4.3 states that the limestone piece is to be removed from joint to joint. It then references details on S2.0. Detail 7/S2.0 shows a limestone dutchman repair at this location.

Please confirm if a dutchman repair is to be installed and if so, the extent of the dutchman.

ANSWER: As related to the damaged limestone panel shown on sheet AD2.2, the note should direct the Contractor to repair the damaged limestone panel per details 4, 6, and 7 on sheet

S2.0. The extent of the repair is limited to one limestone panel. The size and thickness of the entire panel is assumed to be 1’‐6” wide x 5’‐0” long, and the thickness varies from 6” to 12”.

44. During the presentation at the site walk, the NPS noted that they would like a hardened tunnel access to the monument through the portico. Is there a specific requirement or look that the

NPS would prefer or is this a means and methods item? Does access to the gift shop through the portico need to be maintained? Is there a specific width that the NPS would like to see for the hardened tunnel?

ANSWER: The government’s intent is that any scaffold being erected under the Portico Ceiling area for work access will need to provide an opening so as to allow the public access into the chamber areas and the gift shop, etc. If the scaffold is to cover the entire Portico Ceiling area, then an opening will need to be provided to allow the public to pass through into these areas.

The opening will need to provide adequate protection from falling debris or other hazards.

Assume a minimum width of approximately 10 ft, however, the final layout and design of this space shall be submitted by the contractor for NPS and USPP review, and alternate solutions to accommodate this can be considered.

45. Please provide the weight of the heaviest section of stone to be removed from the Portico roof.

ANSWER: Condition not verified by design team. Contractor to field verify and/or calculate based on the sizes of the roofing elements as shown on sheet AR8.1 and the average weight of

Vermont Imperial Danby marble.

46. Please advise if it is acceptable to submit PPQ's on other formats, for example, the NAVFAC PPQ.

ANSWER: It is acceptable to submit other formats such as NAVFAC PPQ; however, it is offeror’s responsibility to ensure all the information National Park Service is requesting is reflected in the other PPQ format.

47. Please specify the source and the location of any available power exterior of the monument around the staging area.

ANSWER: Sources and locations of available power for the staging area are shown on sheets

AR1.1 and AR1.2. Sheet AS1.0 indicates location through which Contractor should run power from the undercroft to the staging area.

48. Please specify the lighting and electrical requirements for the security gate, security trailer and vehicle company.

ANSWER: These requirements will vary based on the products submitted by the Contractor and approved by the NPS/USPP.

49. Please clarify the warranty exception stated in the roofing specification 075419‐2‐1.5A‐3a as roofing companies will not warranty a roof for roof traffic.

ANSWER: Paragraph 1.5A.3 in specification 07 54 19 should read: “3. Exceptions NOT Permitted:

a. Damage due to wind of speed greater than 56 mph but less than 100 mph.” The language referring to damage due to roof traffic has been removed from this section.

50. Note 1.8 on AS1.0 notes that an accessible path needs to be maintained. The current path

(sidewalk) goes through the middle of the secure area proposed. Does this sidewalk need to be maintained to allow access or is an alternate accessible path able to be created along the secure fence line?

ANSWER: Note 1.8 has to do with the contractor protecting existing curbs, sidewalks, exposed aggregate concrete sidewalks, etc. within the limits of work and staging area. This question refers to Note 1.7 on sheet AS1.0. The pathway in question that runs into the middle of the secured fence area does not need to be maintained as a public path. This pathway call be blocked by the NPS (Park) indicating that it is closed, and directing visitors to other access points to the Memorial. Pathways outside of the secured perimeter shall be maintained as accessible per specifications section 01 11 00 – Summary of Work, section 1.5 Occupancy Requirements for

Buildings, paragraph 1.b.

51. Spec 01 57 19.11 states that an IAQ plan is required. Is this applicable to this project as it is an open structure?

ANSWER: An Indoor Air Quality Plan (IAQ) will still be required to address those spaces that are enclosed and occupied, that may be affected by construction operations above them, such as the Bookstore, and the other spaces below the attic. We anticipate that this plan would not need to be overly extensive such as for an occupied office building.

52. The specifications note several LEED requirements. Is this project going for a LEED certification?

ANSWER: No. This project is not seeking any LEED certification. There are no specific references to LEED within the specifications.

53. The specifications note that any use of water on the stone has to be at temps above 50 degrees however most of this work is being performed during winter in an enclosure and the laser cleaners require a quick mist on the stone for the laser. Will this be acceptable?

ANSWER: Contractor to submit an alternative work plan as directed by specification 04 01 40.91

1.9B if work is to be performed below 40 degrees Fahrenheit.

54. Is the intention for the laser cleaning to be done in the joints as well as the skyward facing surfaces or is the requirement just for exposed surfaces?

ANSWER: Yes, the joints as well as the skyward‐facing surfaces should be laser cleaned as described in specification 04 01 40.52.

55. Note 5.1 on AD1.0 states the copper straps are type 2 salvage demo. However, note 5.1 on A1.0 states that the copper straps be reinstalled. Which of these notes should be followed?

ANSWER: Follow note 5.1 on sheet AD1.0 as directed. See sheet E2.1 for new work related to the lightning protection at the portico roof.

56. Reference Section 04 01 40.52‐3.8.B the sequence is indicated as follows “Perform laser ablation after general cleaning of marble using low‐pressure water rinsing and after raking of mortar joints but before repointing”. 1) By including the raking of mortar joints, the sequence appears to assume that CLIN No. 4 will be accepted. Please confirm that the base bid does not include the raking of joints and thus the referenced section should indicate “after raking of mortar joints [if CLIN 4 is accepted]”. 2) If CLIN 4 is accepted, the sequence is unclear with respect to the raking of the joints versus the low pressure water rinsing. Please advise as to the preferable sequence.

ANSWER: Base bid does not include repointing from the top of the dome to the bottom of the architrave. If CLIN 4 is accepted, the sequencing of the low‐pressure water rinsing and raking will be clarified by the NPS prior to the beginning of work.

57. Reference Section 04 01 40.52‐3.8.D, which indicates “Cleaning: Perform laser ablation on entire exposed surface of stone. Apply laser pulse only as long as visible staining remains. If soil or stains remain after laser ablation procedure, repeat the general marble cleaning process specified above.” It is not possible to accurately quantify the amount of soiling or staining that will remain after completion of the laser ablation procedure until after the testing and mockups have been performed. For the purpose of the bid, may we assume that five percent (5%) of the surfaces will require a repeat of the general marble cleaning process?

ANSWER: The expectation is that the Contractor will evaluate and manipulate the laser parameters during the mock‐up process until a fully successful level of clean is achieved, to the satisfaction of the Contracting Officer. The Contractor's mock‐up shall serve as the standard to which the remainder of that work shall be held until that work is complete.

58. Reference Section 04 01 04.52‐1.3.B.2 which requires “Laser cleaning shall be carried out by a steady crew of skilled technicians who are thoroughly experienced with materials and methods specified and have a minimum of three years’ experience laser cleaning white marble similar to the work required by this Section.” Based upon the production indicated in the Draft Record of

Treatment (Approximately 2 sf/laser‐hr) applied to the square footage of laser cleaning indicated on A3.1 (35,300sf), the project will require 17,650 laser‐hours. Based upon the bid schedule, 17,650 laser hours will require 10+ laser technicians working full time. We are not aware of a qualified laser cleaning subcontractor that has 10+ laser technicians on staff that meet the three‐year experience requirement. May we request that the laser technician experience requirement be revised such that the technicians have a minimum of one (1) year of experience laser cleaning white marble similar to the work required by this Section, but supervised by a foreman having a minimum of three years’ experience laser cleaning white marble similar to the work required by this Section?

ANSWER: The Record of Treatment was provided as information only. The Contractor shall develop its own means and methods, including, but not limited to, production rates and manpower/staffing plans, that fully and successfully complete the work specified in this section.

The laser technician experience requirements have been changed to allow for technicians that have a minimum of one (1) year of experience laser cleaning white marble similar to the work required by this project if the supervising foreman has a minimum of three (3) years’ experience laser cleaning white marble similar to the work required by this project. See below response to question regarding clarifications to specification section 04 01 04.52.

59. Please provide elevation and cut details of the limestone pieces to be replaced per note 4.1 on

S2.00.

ANSWER: This question is assumed to refer to the replacement limestone pieces at the portico ceilings. Elevations and cut profiles of the limestone pieces are to be field verified by the

Contractor.

60. Please confirm no cleaning or restoration of any stones below the B.O. Architrave.

ANSWER: No laser cleaning is to be performed below the bottom of the architrave. Other types of cleaning and restoration of the stones below the bottom of the architrave shall be performed as directed in the drawings.

61. Please confirm the sequence of activities during the laser cleaning. We propose low water pressure cleaning first, joint raking second, laser cleaning, and then repointing.

ANSWER: If CLIN 4 is accepted, the sequencing of the low‐pressure water rinsing and raking will be clarified by the NPS prior to the beginning of work.

62. Please provide pointing detail/cut for the dome stones.

ANSWER: The marble stones at the dome are to be pointed per section 04 05 13.91.

63. Per note 1.5 and 4.10 on A2.1 – please confirm that these indicate two single panels only.

ANSWER: Assumed note 4.5 is being referred to and not 1.5. The paired 4.5 and 4.10 notes on

Drawing A2.1 refer to a total of two stone soffit units, including the mortar joints adjacent to these units. Note that other locations of 4.5 on the portico ceiling are shown on Drawing A2.4.

64. Per note 4.14 on A1.8 – please confirm that these Dutchmen will be for single stones at teach location. The marking of locations on this page is over the corner of 3 and 4 stones.

ANSWER: Correct, the dutchman repairs indicated are for single stone units (at the ridge cap).

65. Per note 4.0 on A1.7 and A1.8 – please provide a typical length of each of these cracks.

ANSWER: Assumed note 4.9 is being referred to and not 4.0. Contractor to assume length of each crack is approximately 2‐4” in length.

66. Per Spec section 040140.52 – 3.8.B the sequence for laser ablation includes the raking of joints, however per the proposal the repointing will be an option, please confirm that the raking and repointing will be needed at the dome for laser cleaning.

ANSWER: If CLIN 4 is accepted by the NPS, then the sequence will include raking of the joints.

67. Reference General note 1.4 on A3.1 and Section 04 01 40.52. Please confirm that the intent of the Bid Documents, is to perform laser ablasion on all white marble surfaces from the Architrave to the top of the dome as a means to remove biofilm, and accordingly any “cleaning” that results from the low pressure water rinse that precedes the laser ablation will not in any way serve to reduce the total area of laser ablasion to be performed.

ANSWER: Confirmed. Laser ablation will be performed on all marble surfaces from the top of the dome to the bottom of the architrave in addition to the low‐pressure water cleaning that precedes the laser ablation.

68. Please clarify the following sections of specification 04 01 40.52: 1.3B, 1.4B.2, 1.5B.4, and 3.8A.

ANSWER:

a. Section 1.3B should read:

Laser Cleaning Specialist: Award laser cleaning work to a firm that can demonstrate to the Contracting Officer’s satisfaction that, within previous five years, the firm has successfully completed at least three laser cleaning projects on historically significant buildings and/or freestanding sculpture similar in type to work required on this Project.

At least one of the projects cited for experience shall involve laser cleaning of white marble. (Section continues without change…)

b. Section 1.4B.2 should read: Laser Cleaning Specialist:

For firm, provide a list of at least three laser cleaning projects on historically significant buildings and/or freestanding sculpture similar in type to work required on this Project and evidence of laser safety training. At least one of the projects cited for experience shall involve laser cleaning of white marble. For each project, list project name, address, architect, conservator, supervising preservation agency, scope of contractor’s work, and other relevant information. Foremen shall have a minimum of three years’ experience laser cleaning white marble similar to the work required on this Project. Technicians shall have a minimum of one year of experience laser cleaning white marble similar to the work required on this Project. Only personnel whose qualifications have been submitted and approved will be allowed to perform the work.

c. Section 1.5B.4 should read:

Cleaning Marble Masonry Using Laser Ablation: Following preparation of general cleaning test panels, perform laser ablation on the cleaned test panels. Prepare additional panels using different parameters as directed. Successful tests panels will be those that meet the satisfaction of the Contracting Officer.

d. Section 3.8A should read: General: Remove black biofilm from the exposed marble surface after surfaces have been cleaned with low‐pressure water rinsing using the gentlest means possible without damage to the marble surface. Perform laser ablation on marble using laser system, equipment and parameters selected during the testing included in Paragraph 1.5.B.4 of this specification section and confirmed during the mock‐up included in Paragraph 1.6.B.4 of this specification section to achieve marble surface free of biofilm to Contracting Officer’s satisfaction.

69. Is there only one contractor that meets the qualifications required to perform the laser cleaning work?

ANSWER: No. There is more than one contractor that meets the criteria in the specification as issued and clarified through the addenda.

70. Please extend the bid due date one week.

ANSWER: The bid due date is not extended. Proposals remain due on Monday, August 27, 2018 at 1200 MT.