18b3_RFI_no_1.docx

FA875118B0003

REQUEST FOR INFORMATION #1

Q1) On drawing S-102, MEP floor opening frames are called out between column lines 4-5 and references typical details but there is no further call-out for what size angle or other material to use. Please advise.

A1) Contractor shall utilize the attached sketch AD S-505.

Q2) The caissons for the antenna foundation alternate.

1. The Caisson spec states to review the geo-tech report, but the geo-tech report is not included in the project documents. Please provide geo-tech report.

2. Several casing references, temporary to permanent ? do they want permanent ? if so what wall thickness.- none shown

3. Trial pier – do they actually want one / again with permanent casing ?

4. Reference “bells” - none shown, and on rock –NONE required (standard practice)

5. low alloy” - reinforcing steel – in drilled pier spec – are you covering rebar ??

6. Casings – mentioned again in spec, including a Liner ? ACI 336.1 ??

A2) 36” diameter drilled piers are shown on the drawings with a depth of approximately 20 feet below grade. Bells are not required on the piers. It is expected that casings will be provided to allow safe entry for inspection, but the casings need not be permanent. They may be left in place at the contractor’s option at no extra cost to the project. Thickness of the casings shall be at contractor’s option as suitable for the application. For bid purposes the drilled piers should be assumed 20 feet long and a unit price should be provided in the bid to reduce the price if shorter piers are required and another unit price to increase the pier length if required. Pricing should be inclusive of all costs related to drilling, temporary casings, reinforcement, concrete and schedule extension related to the work and materials procurement. The contractor may provide at their option low alloy reinforcement suitable for welded splices OR standard reinforcing with laps or approved suitable mechanical connectors for the drilled pier vertical bars. Reinforcing is not coated.

Q3) Spec Sec 099123 Interior Painting – Painting Schedule does not include paint systems for exposed steel and metal decking, hollow metal doors and frames. Please provide.

A3) Finish criteria are listed in the individual sections.

[For example, Hollow Metal Doors and Frames - refer to Section 081416, page 8, etc.]

For additional clarification:

Steel Substrates (Doors/Frames):

Steel and Iron Substrates:

1. Water-Based Light Industrial Coating System (MPI EXT 5.1C):

c. Topcoat: Light industrial coating, exterior, water based (MPI Gloss Level 3), MPI #161.

Galvanized-Metal Substrates:

2. Latex System (MPI EXT 5.3H):

Q4) Please verify that all work shown on C-002 Demolition Plan (attached), per the note on this drawing, is to be included in Additive Bid #2 – Building Demo.

A4) All work associated with the removal of the existing building & existing features, paving, septic tank, bollards, and satellite dish bases is considered inclusive of the Bid Alternate.

Q5) In the solicitation Section B states:

ITEM No. 0002 - Additive Bid 1 - Contract consists of furnishing all labor, equipment, devices, and materials and perform all work required to complete alternate silo foundation listed as Bid Alternate Item 1 in accordance with the Project Technical Specifications and Project Drawings

ITEM No. 0003 - Additive Bid 2 - Contract consists of furnishing all labor, equipment, devices, and materials and perform all work required to complete alternate Building 1600 listed as Bid Alternate Item 2 in accordance with the Project Technical Specifications and Project Drawings

But specs and drawings state:

Please clarify.

A5) The correct order of priority is:

ITEM No. 0002 - Additive Bid 1 - Contract consists of furnishing all labor, equipment, devices, and materials and perform all work required to complete alternate silo foundation listed as Bid Alternate Item 1 in accordance with the Project Technical Specifications and Project Drawings.

ITEM No. 0003 - Additive Bid 2 - Contract consists of furnishing all labor, equipment, devices, and materials and perform all work required to complete alternate Building 1600 listed as Bid Alternate Item 2 in accordance with the Project Technical Specifications and Project Drawings.

Q6) Please provide specifications for Security Fencing & Gates shown on AE 201 - AE-204.

A6) Contractor to refer to attached Specification 027000 - CHAIN LINK FENCES AND GATES.

Q7) The specification 33 2000 Water Well installation refers to “contract unit price” Please advise, there is no unit price schedule.

A7) Because this is a lump sum bid, the reference to "contract unit price" in the spec can be ignored.

Q8) Is there an onsite disposal area for clean demolition materials? Or will it be required to be transported off-site?

A8) Disposal of clean demolition materials will be at an off-site location. Selection of the site, transportation, and disposal is the Contractor’s responsibility.

Q9) Please provide a geotechnical report, to verify depth to bedrock for existing foundations, trenching, etc.

A9) A geotechnical report is attached.

Q10) On sheets S-102 and AE202, 20 lf of Removable Railing is indicated on the structural steel loading platform at the east end of the upper mezzanine. Please provide a detail addressing the removable guard rail at this loading platform.

A10) Contractor shall provide an 8” tall, 1-3/4” diameter pipe sleeve, welded to the MC channel, similar to handrail detail #5 on Sheet S-507.

Q11) 1 – Please confirm that all speaker/strobes for mass notification and fire alarm notification are speaker/strobes and not horn/strobes.

2 – Please confirm that differentiation between mass notification and fire alarm notification speaker/strobes can be made by appliance color and lens color.

- Ex. A fire alarm notification speaker strobe will be a red appliance with clear lens and a mass notification speaker strobe will be white with an amber lens.

3 – Will mass notification and fire notification audio be controlled by the fire alarm panel or by another method?

speaker/strobes can be made by appliance color and lens color.

3. The design intent is to have both fire alarm and mass notification systems controlled by the same Fire Alarm Control Panel.

Q12) 1) On Drawing # S-900 / Detail #1; shows the top of the pile cap @ elev. 0’-0”. What is the actual Datum Elevation of 0’-0”?

2) Spec Sec 055119 Metal Grating Stairs & Spec Sec 055313 Bar Gratings - There are conflicting specifications for bearing bar thickness:

* Spec Sec 055119 2.6.C.1 - 1 by 3/16” bearing bars

* Spec Sec 055313 2.2.B.3 - Bearing Bar Thickness: ¼”

Suppliers that are bidding do not make a 1/4” thick bearing bar grating. Is 3/16” bearing bars acceptable for Spec Sec 055313? Please advise.

A12) Top of foundation/pier elevation shall be field coordinated. The exact location of the tower was not known at the time of geotechnical investigation. The intent of the spec is to have one trial pier that confirms required depth and allows access for the geotechnical engineer to inspect the rock and take additional samples as required to verify foundation design. The trial pier can be placed in the vicinity of the production piers as directed in the specification, or at the contractor’s option the trial pier may be the first production pier, but as mentioned in the RFI question, the rock testing may take time and the casing therefore might not be removable. The contractor will not receive additional compensation for casings left in place. Rock core testing is not required except in the trial pier, but the geotechnical engineer will need access to each hole to visually confirm the strata.

A 3/16” bearing bar is acceptable to use in lieu of the ¼” bearing specified in Sec 055313 2.2.B.3.

Q13) RFI regarding Spec Sec 316329 – Drilled Concrete Piers and Shafts:

1) Part 1.9 – Trial Shaft

· Please verify that this will be required?

· Can the production shafts begin immediately following the trial shaft?

2) Part 3F & 3G

· These two sections contradict each other with respect to the depth of the rock probe holes. Please identify what the length of the rock core should be.

· All four caissons are within a dozen feet apart from each other, is it necessary to test the quality of the rock at more than one location?

The following is a step by step procedure to test the bearing capacity of the rock in accordance with the way this section of the spec is written.

· Drill and install a steel temporary casing pipe down to the top of rock.

· Core drill the rock socket to designed depth.

· Geotech company core drills the rock probe hole (approx. 2” dia.) to the (above identified depth) beyond the bottom of the rock socket.

· A geotech engineer will enter down inside the temporary casing pipe and scrape the sidewalls of the rock probed hole with a feeler gauge in search of voids.

· The rock core is taken back to the geotech’s lab for compression testing.

· Geotech engineer will provide bearing capacity recommendations to the project structural engineer after the testing is complete.

· Project structural engineer may/may not re-design the rock socket length of one or more caissons based on the geotech engineers recommendations.

· Rebar cages may have to be spliced to accommodate for the new designed lengths.

· Upon re-working of the rebar cages, the caisson contractor can resume the caisson foundation work.

There are many claims for additional compensation when the above is required. It has been recommend by the drilling subcontractors that the geotech of record obtain the rock cores in advance to fabricating the rebar cages and before the specialty foundation contractor is mobilized to the site. Please advise which method above will be implemented?

3) If the rock probes are to be performed as specified, please clarify the following:

- Who hires the geotech engineer and obtains the (quantity of ?) rock probes?

- How is the contractor compensated for adding lengths to the rebar cages ?

- How is the drilling contract compensated for the delay time waiting for the final design lengths?

- Line item for permanent casing; Depending on the number of days and the soil conditions that the temporary casings are left in the ground, they may not be able to be removed.

The owner will provide inspection and testing services for the process as outlined above.

It has been suggested that it may be economical to do 4 location specific rock cores ahead of drilled pier production by using a separate standard exploratory drilling rig in order to minimize down time of the large diameter drilled pier equipment and to finalize reinforcement cages prior to production drilling. This approach is acceptable, but the contractor shall be responsible for the cost of the exploratory drilling including all mobilization and demobilization of the equipment, equipment charges, and drilling rig operators. The contractor will be responsible for drilling deep enough to reach acceptable bearing strata, and shall grout fill the rock after drilling. The owner will only provide geotechnical engineering services related to laboratory inspection and testing the rock core. If this approach is used, the geotechnical engineer will NOT need access for visual inspection of each drilled pier. For bidding purposes the drilled piers should still be assumed 20 feet long and an add/deduct should be provided for shorter or longer piers.

Q14) What is the specific detail for the removable railing? Can you provide a sketch?

A14) Contractor shall provide an 8” tall, 1-3/4” diameter pipe sleeve, welded to the MC channel, similar to handrail detail #5 on Sheet S-507.

Q15) Colden Corp’s summary of asbestos sampling results (Table 1 Summary of Asbestos Bulk Sampling Results) shows 1x1 tiles in selected rooms as containing Chrysotile. However, tiles with the same appearance as those tested in selected rooms exist in rooms that were not tested. Do those tiles in rooms not selected for testing also contain Chrysotile?

A15) Those tiles in rooms not selected for testing contain Chrysotile.

ADDITIONAL INFORMATION

- The Government will remove any and all dish type and non-dish type antennas from on top of the building and inside the building. That includes the equipment in and on the steel silo.

- Selected Building 1600 construction drawings are provided for reference.