Attachment 4.pdf

JFTB HANGAR 1 REPAIRS PHASE 2

ADDENDUM 1 – 9 MARCH 2010

CLARIFICATIONS

DRAWINGS

Sheet A-2, Construction Note 5 & A-4, Construction Note 2 add the following:

Painting and lead paint stabilization shall include all previously painted surfaces at the ceiling area of Hangar Room 120 including all structural supporting members and items attached thereto such as electrical conduit, plumbing pipes, equipment supports, catwalks, railing, etc. See additional clarification in response to Allen Engineering RFI #3.

Sheet A-4, Construction Note 1 add the following:

Paint all previously field painted items attached to or adjacent to walls including but not limited to door frames, doors, signage, electrical conduit, plumbing pipes, hoist equipment, etc. Paint all new fire suppression piping.

Sheet M-6, Detail 4: Note for connection to A.C. unit is “(3)#12 Galvanized SMS w/ 1/2” min edge distance. Apply sealant around screw.”

Sheet P-5: All compressed air piping shall be black steel schedule 40 per sheet P-1 and specification section 15481 Compressed Air Systems.

Sheet E-1: 400 Hz Receptacle shall be Meltric Model DSN60 Part# 63-64167-345-A188 with Self-Ejecting Connector Release or equivalent. 400Hz Receptacles shall be installed with Meltric Metal Box with Nylon Angle Part #61-6A053-080-1 or equivalent.

SPECIFICATIONS

Site Specific Lead Abatement section 02090 pages 1 through 32 (after data charts). Change footers to read as follows:

GENERAL LEAD ABATEMENT 02095 – 1 THROUGH 32

DEMOLITION PHOTOS

RESPONSE TO PRE-BID RFI’s

1.01 Q: Will a separate Q.C. Manager be required, making this a 3-hat project?

A: A separate Q. C. Manager will not be required.

1.02 Q: Per section 01500-1.06 will a Government Field Office be required? There is not one currently being supplied for Phase 1 improvements. Please clarify.

A: A Government Field Office will not be required.

1.03 Q: The scope for the Painting is unclear. The Drawings seem to only include the interior of the Hangar as well as some miscellaneous items. The Specifications refer to exterior roof painting, sheet metal painting and door finishes. It is also unclear if the perimeter rooms are to be painted as well. Can a Finish Schedule be provided to show all rooms/doors to be painted/refinished?

A: Hangar room 120 is the only room indicated for painting. Exterior painting will be limited to items being provided in this Contract, eg: Steel pipe bollards and fire suppression piping.

2.01 Q: Miscellaneous Steel. The generator support tubes called out on details 6 and 7/S3 says they are to span C purlin to C purlin. However the drawings do not show where the C purlins are located or how far they span. Please advise.

A: The C Purlins occur at the underside of the roof sheathing in the main hangar area and are spaced at intervals of 7’-0” to 8’-0” on center. C purlins span between the steel truss top chords, which are spaced 20 feet on center. The exact length of the HSS Members shown in Detail 7 / S-3 shall be determined by field measurement by the contractor.

2.02 Q: Flooring. Ref: Spec Section 09960 – 1.01 - How many minimum mils Dry film Thickness are requested for the Sikafloor 107, 207, & 310?

A: Per Manufacturer’s instructions: 107 requires 8 mil minimum dry film thickness;

207 requires 8 mil minimum dry film thickness; 310 requires 4 mil minimum dry film thickness.

2.03 Q: Flooring. Will grinding down the raised floor joints and/or filling in the broken joints be required to eliminate trip hazards?

A: Yes, see spec. 09660, Par. 3.03 & 3.04.

2.04 Q: Flooring. Please confirm if existing concrete floor coating in hanger bay contains asbestos and will require abatement. Please note that any asbestos floor coating will need to be fully abated so we can warranty the epoxy flooring to the concrete.

A: The existing floor is not identified as having a coating and is not identified as having asbestos containing materials on its surface.

2.05 Q: Flooring. What size holes and cracks are to be patched in concrete floor in hanger bay? Industry standard is 1 inch in diameter holes and cracks greater than 1/8th inch wide.

A: Fill ALL cracks and holes that can transfer through the floor coating system.

2.06 Q: Flooring. Please confirm if the existing grounding rings in hanger bay will need to be replaced with new grounding rings.

A: The grounding rings will not be replaced.

2.07 Q: Mechanical. Ref: Note 17 on sheet M-1 – Verify which walls are considered “fire-rated”.

A: No walls are considered fire rated.

2.08 Q: Mechanical. Ref: Note 7 on sheet M-1 – Clarify if new ductwork, grilles, and manual volume dampers are to be required; if required please confirm locations. There seems to be a conflict between Note 3 on detail 3 & 4/M-3 and Note 7 on sheet M-1. Note 3 indicates that the control wires for thermistors are to be routed back to AC unit on roof which implies that the VAVs are to be controlled at the AC unit. Note 7, however, indicates that manual volume dampers are to be required. The manufacturer has indicated that VAVs are not integral to the unit. We suggest locating VAVs inside the building at the most appropriate locations for each zone. Please advise.

A: The ductwork has manual volume dampers already installed in the branches. If there is not a volume damper or a broken volume damper, a new one shall be provided to balance the diffuser and zone. The multi-zone VAV system is a complete packaged system where the VAV boxes (modulating zone dampers) are in the rooftop A.C. Unit. The thermistors send a signal to the rooftop unit to adjust the VAV dampers in the rooftop unit.

2.09 Q: Mechanical. Ref: Note 2 on sheet M-1 – Please provide the Architectural Reflected Ceiling Plan, Electrical Lighting Layout, and Architectural Room Elevations for the staff offices and rooms not in the hanger bay.

A: Note 2 does not apply.

2.10 Q: Environmental Ceiling and walls LBP removal. Please confirm that the intent for removal on the ceiling wood/truss system along with the interior walls systems is for stabilization only. One note states removal of top coat and all underlying coats regardless of the number of coats. Another note requires stabilization, the LBP specification plan suggests stabilization we interpret this as applying loose and failing paint only.

A: The scope is to prepare the substrate for new paint. The general contractor will warranty the new paint systems. The following practices will be included (but not limited to): All areas will be cleaned, sanded, and scraped to the recommendation of the painting contractor and paint manufacturer. All areas exhibiting rust and extensive buildup of paint will be sand blasted to the substrate. All areas where the paint system is compromised in any way will be scraped or sanded. After primer has been applied any lifting paint will be scraped prior to additional painting.

2.11 Q: Epoxy floor coating. The LBP survey identifies the yellow striping paint on the floor surface as lead containing, we do not see any analytical for the epoxy floor coating;

typically on these older systems the underlayment coat on the concrete contains lead.

When prepping the floor for the new epoxy system there will be areas that need removal to the concrete substrate which will require removal of all coatings. Is there LBP under the epoxy?

A: There is no existing epoxy floor coating.

2.12 Q: Epoxy floor coating. Ref: Spec Section 02085 – 1.10 – Please confirm which permits/ pre-notifications are required.

A: The contractor is required to notify state and local agencies prior to the commencement of abatement activities. These notifications are required to be maintained throughout the project. Other notifications may be required to California Department of Health Services.

The contractor is required to provide all notifications required based on the method of abatement chosen.

Permits are required for certain machinery used in abatement. The contractor is required to provide permits for machinery, devices, and methods as required by federal, state, and local agencies.

2.13 Q: Epoxy floor coating. Ref: Spec Section 02825 – 1.15 – Please confirm which school district will require coordination with environmental site security.

A: No school districts are involved in this project.

2.14 Q: Demolition. At the pre-proposal conference, the Government indicated that items that will need to be demoed will be identified in an Addendum. Please identify all items that are to be demoed.

A: See items identified with photos in clarifications.

2.15 Q: Painting. Please confirm exactly what the painting scope of work is. There seems to be a conflict between the drawings and Spec Section 09910 – 1.01 which indicates that the painting scope includes “exterior items and surfaces”, “exterior and interior plumbing”, and “mechanical and electrical work located within work areas and rooftops”. This scope is not indicated in the drawings.

A: Drawings indicate areas that require interior painting. Exterior painting will be limited to items being provided in this contract, eg: steel pipe bollards and fire suppression piping.

2.16 Q: Fire Suppression. Drawing F-2 shows two separate locations for the Fire Alarm Control Panel & Emergency Voice Evacuation Panel (Passage Corridor near Vault 122 and across from Office 111). Please clarify panel location and/or intent of two locations.

A: The passage corridor on the north end of the building will contain the main fire alarm control panel, the foam releasing panel, and voice evacuation microphone station with selectable prerecorded messages. The wall across from Office 111 on the south end of the building will be provided with a remote voice evacuation microphone station with redundant controls, and a remote LCD annunciator with acknowledge, silence, and reset functions.

2.17 Q: Plumbing. Ref: Sheet P-4 – The radiant gas heaters do not seem to be vented.

Please provide direction as to how the heaters will be vented if required.

A: Venting is being provided with louvers at skylight end walls in Phase 1.

2.18 Q: Plumbing. Spec Section 15481 – 3.07B – This section requires the air compressor to be mounted on a 4” high reinforced concrete pad. Detail 6/P-7, however, does not show a 4” concrete pad. Please confirm if the 4” concrete pad is required for the air compressor.

A: The air compressor can be bolted directly to the existing concrete slab. Use expansion bolts into concrete with 3” embedment. Use isolator pads to reduce vibration and noise per specifications.

2.19 Q: Please confirm if it is acceptable to work 4 – 10 hour days per week rather then 5

– 8 hour days per week without any additional expense as indicated in Spec Section 01000 –

1.03. We would prefer to work 4 – 10 hour days in order to increase weekly productivity.

A: A 4 day – 10 hour/ day work schedule is acceptable. Monday through Thursday.

Holiday schedule remains the same.

2.20 Q: Please confirm the completion date for Phase 1 contractor.

A: Current completion date is 1 July 2010. This date is subject to change due to circumstances outside of the Government’s control.

2.21 Q: At the pre-proposal conference, the Government indicated that the Phase 1 contractor had #1 priority over the Phase 2 contractor. Lead abatement will be our first task for Phase 2. Please advise on how we will be able to abate while the Phase 1 contractor is on site.

A: Sections of the hangar area can be phased and cordoned off pending coordination with the other phase contractors. The sections may be as large as one quarter of the ceiling area with 4 separate containment zones.

2.22 Q: Please note that the sheet E-1 shows new light fixtures as 277V, however, the existing panels feeding these fixtures are 120V per sheet E-9. Please advise.

A: The voltage should be 120V, since each lighting circuit is supplied through one 120V circuit breaker, and one neutral conductor. "277" should be changed to "120" in the light fixture schedule. The Holophane Enduratron Catalog No. must be changed accordingly. A 120 Volt, or a multi-voltage ballast will be needed. The code for 120V is "12". The code for multi-voltage is "MT" Holophane will have to be contacted for the exact Catalog No.

END PHASE 2 ADDENDUM 1