February 25, 2003

CONTRACT NO. 04-0120G4
County Route: SF-80-7.9/0.0


The responses to contractors' inquiries, unless incorporated into a formal addenda to the contract, are not a part of the contract and are provided for the contractor's convenience only. In some instances, the question and answer may represent a summary of the matters discussed rather than a word-for-word recitation. The responses may be considered along with all other information furnished to prospective bidders for the purpose of bidding on the project. The availability or use of information provided in the responses to contractors' inquiries is not to be construed in any way as a waiver of the provisions of section 2-1.03 of the Standard Specifications or any other provision of the contract, the plans, Standard Specifications or Special Provisions, nor to excuse the contractor from full compliance with those contract requirements. Bidders are cautioned that subsequent responses or contract addenda may affect or vary a response previously given, and any such subsequent response or addenda should be taken into consideration when submitting a bid for the project. Inquiries submitted within seventy-two (72 ) hours of the bid opening date might not be addressed.

The Caltrans District 4 Office is located at 111 Grand Avenue, Oakland, CA 94612. Send Contractor Inquiries via email to the Duty Senior at The mailing address is P.O. Box 23660, Oakland, CA 94623-0660. The Duty Senior's telephone number is (510) 286-5209 and the fax number is (510) 622-1805. All inquiries must include the contract number.

Total Number of Inquiries:26


When can we have a site visit

A site tour will be conducted on Thursday, February 6 and Thursday, February 13, 2003. The tour will commence at 10:00am. To reserve a space for a site tour, contact the District 4 Duty Senior by fax or e-mail. The District 4 Duty Senior fax number is (510) 622-1805 and the e-mail address is Click here to view more information and to reserve a space on-line.


Reference to Notice To Contractors, please provide location for the pre-bid meeting on February 5, 2003 at 9:30 a.m. to 12:30 p.m.

The meeting will be held at the Holiday Inn Bay Bridge, 1800 Powell Street, Emeryville, CA 94508. See Addendum #1


Reference to the Standard Specifications dated July 1999, Section 8, Paragraph 8-1.01 Subcontracting, third paragraph regarding requirement of contractor (Prime Contractor) to self perform work amounting to no less than 50% of the original total price. It appears that Electrical is the major trade of this project, but we are unable to determine if Electrical Cost would be more than 50% of the budgeted value. Please re-consider the issue and possibly waive that requirement so that some of the general contractors may bid the project as prime.

See Addendum #2


The Special Provisions state that "Difficult tiedown installation is anticipated due to the presence of caving soils, hazardous and contaminated materials, high ground water, cobbles and boulders, subsurface concrete debris, rock cuttings, timber piles, low overhead clearance, underground utilities, overhead utilities and the requirement of tiedown embedment into rock.

In reviewing contract plans and log of test borings we are unable to find most of the items listed above except for high ground water.

Since the Special Provisions prevail over contract plans and we assume also over the test borings, we are concerned that the Designer may have information regarding site and soil conditions which, based on bid documents we received, was not made available to us.

In order for us to submit a realistic bid (not too high, but not to low) we believe it should be based on whatever information Caltrans has available. We trust you agree and look forward to your prompt reply. Thank you.

The data and information in the Material Information Handout are available on CD ROMs. Contractors that did not receive bidder packages may obtain the Material Information Handouts by contacting the Caltrans Plans Counter, phone (916) 654-4490 or fax (916) 654-7028.


Reference Special Provisions, Section 10-3.13 para. 3
What SCADA RTUs are being provided with the Skyway Contract? Please provide manufacturer and model also include any other communication modules that may also be included.

The SCADA RTU has not yet been provided for the Skyway Project (Contract #012024), but it is planned to use a GE 90-30 PLC, or equivalent.


Reference Special Provisions, Section 10-3.13 para. 3
Is this contract ( 04-0120G4) providing the referenced SCADA Master PLC? or Who is providing the SCADA Master PLC?

No, the Master PLC will be procured and installed by Caltrans in the Administration Bldg.


Reference Provisions, Section 10-3.13 para. 3
What is the manufacturer, model and any other communication modules for the provided SCADA Master PLC?

The Master PLC has not been procured.


Section 10.1.30, Part 3 – Salvage (page 155) states in part that certain items as indicated on the plans and as specified shall be salvaged and reused or delivered to a State storage facility, and includes a list of items to be salvaged. However, there are no quantities indicated, and none of these items appear on any of the plans provided for bidding purposes. Please provide plans or an itemized listing indicating quantities, sizes, ratings, etc. that will enable all bidder’s the opportunity to fully interpret the actual scope of work intended.

The Contractor shall turn over to the State the following electrical equipments:

        One- 15 KV switchgear with three vertical sections.

        One- 300 KVA, 12.47-.480 V transformer.

        All, aproximately fourty 480 V combination starters and feeder breakers.

        One -50 KVA lighting transformer.

All other items such as eight lighting fixtures, pull boxes, raceways, supports and other miscellaneous items that will be removed in the substation shall become property of the Contractor after demolition.


Project Plan Sheet 112, Detail 1 indicates that conduit numbers 3A and 3C are to be extended to utility stations in Vaults #1 and #5. The locations indicating where these vaults are located do not appear on any of the plans provided for bidding purposes. Please provide plans indicating the locations of these vaults, or provide the applicable distances to these vaults from the location provided in Detail 1.

The distance from vault #3 to vault #1 is 334.5 m.
The distance from vault #3 to vault #5 is 68.5 m. 


Project Plan Sheet 128, Sheet Note 2 indicates that the bidder is to intercept existing 15 kV cable and extend new cable to new YBI substation. The location indicating where this splice should occur does not appear on any of the plans provided for bidding purposes. Please provide plans indicating the location of this splice that will enable all bidder’s the opportunity to fully interpret the actual scope of work intended.

Contractor to Intercept existing 15 kV cable in existing vault #4. Splice existing conduit to new #1/0 AWG cable and extend feeder to new YBI substation.  Please note that additional information related to splice location could be found on sheet 111. .


Project Plan Sheet 128 indicates a reference to Sheet Note 3 between existing Pier W-4 substation and existing YBI substation. However, this Sheet Note is not provided on this drawing. Please provide additional information that describes the scope of work intended for this missing note.

The reference to Sheet Note 3 is in error. It should refer to Sheet Note 2.


Project Plan Sheet 91, Sheet Note 10 refers to a temporary cable tray support structure indicated on sheets E-11 and E-19. Sheet E-11 does not show a cable tray support structure, and sheet E-19 was not included with the plans issued for bidding purposes.  In addition, Note 10 instructs the bidder’s to see Architectural Structural drawings.  Upon careful review of these drawings, we have been unable to find any details or information for this support structure.   Please provide plans indicating the details of this temporary cable tray support structure.

The temporary cable tray support will be part of another Contract (YBI Structure). All details for the cable tray supports will shown on YBI Structure Contract.
The YBI Substation Contractor shall provide 1500 mm grounding pigtail for termination by other contractor. .


Project Plan Sheet 126 indicates that Cable Tray Nos. T35 and T41 continue through the garage wall to the exterior of the building at Column Line 4.  In addition, these Cable Trays are also indicated on Project Plan Sheet 160, Section B.  However, the locations indicating where these trays will terminate do not appear on any of the plans provided for bidding purposes. Please provide plans indicating the scope of work intended.

Extend cable tray number T35 and T41 1500 mm beyond Column Line 4.


Project Plan Sheet 195, Cable Tray T33 lists Cable No. 1116, but the size of the conductors required for this cable is not indicated. Please provide the appropriate size for the conductors required.

CKT 1116 is 3/C #6 + G. See Project Plan Sheet 147.


Project Plan Sheets 130, 131, 132, 133, 134, 135, and 136 each refer to Note No. 1 which states; "Single line diagram as shown do not represent physical separation of different contracts.  Refer to other drawings for physical separation of different contracts."  Upon review of other drawings, we have been unable to accurately determine the physical separation of different contracts. Please provide revised plans that would differentiate between the limit of work in this contract, and that work which is not intended to be performed in this contract (i.e. See Project Plan Sheet 128, which clearly illustrates the scope of work intended).

The YBI Substation Contractor shall furnish and install LVCC-A, LVCC-B and LVCC-C. However, most of the 480V feeder circuits from the three LVCCs will be installed by other Contractors. The YBI Substation Contractor shall install all 480V feeder circuits related to YBI Substation electrical components. The YBI Substation Contractor shall furnish and install the following 480V feeder circuits:

Plan Sheet #130: CKT#1110, CKT#1111, CKT#1113, CKT#1114, CKT#1101 and CKT#1102.                                  

Plan Sheet#131: No Circuits.

Plan Sheet#132: 120VAC Feeder Circuit to LVCC-A Relay Cabinet (However, this circuit is internal to LVCC-A).

Plan Sheet#133: CKT#2124

Plan Sheet#134: No Circuits.

Plan Sheet#135: 120VAC Feeder Circuit to LVCC-B Relay Cabinet (However, this circuit is internal to LVCC-B).

Plan Sheet#136: Contractor shall install all circuits. In addition, contractor shall furnish and install transformers and panel boards related to CKT#1119 and CKT#1116.

For other circuits, such as 12.47 KV, call boxes, RTU's and controls, refer to block or wiring diagrams for the physical separation of different contracts.

Note: All circuits to be installed by the YBI Contractor are shown on Plan Sheets #189 through #197.


Detail 1 on E-32 (Sheet 112) shows two lines being pulled from Vault #3 to two (E) utility stations. One line is to Vault #1 and the other line to Vault #5. Our electricians can not determine the distances of these runs from Vault #3, as they can not locate Vaults #1 and #5 anywhere on the drawings. Please advise as to the distances or to the location where these vaults can be found.

The distance from the centerline of vault #3 to the centerline of vault #5 is 68.5m. The distance from the centerline of vault #3 to the centerline of vault #1 is 334.5m.


Sheet E-10, what do the symbols "R", "RC", "BC" and "AB" mean?

The legend for the symbols "RC", "BC", and "AB" is given on ES-1A of the Standard Plans, and "R" is given on ES-1B of the Standard Plans.


Sheet E-31, what are the dimensions of the 5 pull boxes associated with the CCTV circuits?

See pull box schedule on plan sheet E-32.


Sheet E-32,section AA, what is the depth of the pipe rack legs?

The depth of pipe rack legs is 920 mm.


Sheet E-32, section AA, what is the height of the pipe rack cross members?

The bottom of the lower level support to finish grade is 305 mm. The top of the upper level support to finish grade is 760 mm.


Is the roof structurally sloped 4% or is the slope to be achieved by tapered insulation?

Insulation is tapered. See Detail 6 on AA-10 (Sheet 54 of 224).


What is the desired minimum R-Value of the roof insulation?  

The minimum R value should be 4.0 per inch of thickness. The insulation thickness varies. This provides an average R value of about 35 for the roof as a whole.


Where is building #206 in the plans?

Building #206 is adjacent to Building #8, next to the EB off ramp, and is shown on Plan sheets L-1, L-2, and SC-3 (Sheets 4,5, and 31 of 224).


Does item No. 2 in 10-1.31 require the upper and lower deck structures between Bents 30 and 43 to be surveyed? Is the entire tunnel and viaduct to be surveyed?  Is bridge No 34-0004 a separate structure?

Per Section 10-1.31, Photo Survey of Existing Facilities, first paragraph, Item 2, the photo survey shall be conducted between Bents 30 and 43, upper and lower deck structures. The tunnel is not included in the photo survey. The Yerba Buena Tunnel and the San Francisco Bay Bridge Viaduct are part of Bridge No 34-0004.


For safety, what degree of traffic control can we expect when conducting the survey?

Lane closures are available. See Section 10-1.23, Maintaining Traffic, 10-1.24, Closure Requirements and Conditions, and 10-1.25, Traffic Control System for Lane Closures, of the contract special provisions for details and restrictions.


What are the duration and the Engineer’s Estimate for this project?

Engineer’s Estimate is $10,000,000. This is an A+B contract, in which the bidder’s proposal shall set forth the number of working days bid to complete the work. Refer to the A+B Bidding Special Notice in the Special Provisions.