MAY 13, 1998,




The Caltrans District 4 Office is located at 111 Grand Avenue, Oakland, CA 94612. The mailing address is P.O. Box 23660, Oakland, CA 94623-0660. The Toll Bridge Retrofit Duty Senior telephone number is (510) 286-5549, and the fax number for Contractor's inquiries submittals is (510) 286-4563

1)Would contract plan electronic files be available to contractor?

Contract plan electronic files will not be available to contractors.

2) Coastwise trade determination for qualified barges.

"A non-coastwise qualified barge may be used as a moored stationary work platform within the territorial waters of the United States without violating the coastwise laws, provided that it transport neither passengers nor merchandise while under tow between coastwise points." Contractors have to get all the appropriate permits from the US Coast Guard.

3)Does the worker's compensation insurance for this project fall under the jurisdiction of the United States Longshore and Harbor Worker Act or the Jones Act?

The Jones Act (46 U.S.C. & 13 et seq.) applies to seamen and shipping and does not relate to construction workers on the bridge. The Longshore and Harbor Workers' Compensation Act (33 U.S.C. & 901 et seq.) applies to employees engaged in maritime employment. A federal court decision of the Fourth Circuit Court of Appeals has held that a construction worker employment in building a bridge over navigable water, designed to benefit both traffic and navigation, is engaged in maritime employment under the Longshore and Harbor Workers' Compensation Act. (LeMelle v. B.F. Diamond Const. Co.)(1982) (674 Fed2.d 296). Under California law (Lab. Code & 3700), every employer is responsible for being insured against liability to pay workers' compensation. That responsibility is incorporated into the Department of Transportation's (Department) construction contracts under the provisions of the Standard Specifications Section 7-1.01(A)(6) that requires the construction contractor to certify compliance with Labor Code Section 3700.

4)How much ship traffic can be anticipated in the ship channel during the life of the project?

Please refer your attention to the Outside Agencies listed under Section 5-1.23, "Relations with U.S. Coast Guard," in Sub-section "Mooring Plan." These listed agencies might provide you upon request with their projected ship traffic for the life of the projects.

5)Refer to Regionwide Permit # RWP-9, Notice of Intent to Proceed # NO1-96-43, Dated March 14, 1997, Page 6, Paragraph I. a) How does the Contractor determine if the clapper rail and/or the peregrine falcon are present?

By Visual Inspection.

6)What is the potential for either to become present during the life of the contract?

None, evidence of their presence has been found at this location.

7)If either the clapper rail or the peregrine is present what are the methods of relief available to the contractor in terms of schedule, extended overhead, etc.

Please refer to time frames specified in permits to minimize their disturbance

8)We would like to obtain the computer model and acceleration time history as described in the special provisions. Specifically: Will you provide both the IAI-NEABS and ADINA models to us?

The IAI-NEABS and ADINA models are available on disc. Please provide your address and we will overnight mail them to you.

9)Please tell us how and where to obtain the software to use the IAI-NEABS models.

Imbsen and Associates will provide a copy of the executable code for IAI-NEABS and the most updated users manual. This program will be provided , free of charge, for a period of three months. Since the program is not for sale Imbsen will not be providing technical support that a user may need. The program is available for PC or SUN Sparc workstation (OS 3.1). To obtain the program contact David Liu at:

Imbsen and Associates
9912 Business Park Drive, Suite 130
Sacramento, Ca. 95827
Phone(916) 366-0632
Fax(916) 366-1501

10)Can "Seismic Energy Products" be recognized by Caltrans as an approved Alternative Bearing prior to the bid opening?


11)A dimension is missing in Section B-B on contract plan sheet 136 of 190. While trying to verify pay quantities for bid item 37 - Structural Concrete, Bridge, it seems that a dimension is needed to adequately take off the portion pertaining to the piers. Section B-B shows the height of the columns, and the height of the sloping concrete walls, however the remaining dimension is absent for said piers.

The elevation for the rocker bearings is provided in the rocker bearing details in the As-built plans. The top of concrete pier elevation can be calculated from the rocker bearing elevation provided.

12)In reference to details on contract plan sheets 134, 135, 137, and 139 of 190. Section D-D on sheet 134 shows the #5 bar to be drilled and bonded at 16" horizontally and 12"O.C. vertically. However, Section J-J on sheet 135 shows what appears to be the same bar drilled and bonded at 12"O.C. bothways. Which bar spacing is correct.

There is no conflict, Section D-D is taken through the upper wall, above the slab, and applies only in that region. The drill and bond note referred to in Section J-J applies only to the pier section below the slab.

13)Please send drawings and information required for us to review and quote on the "seismic isolator bearing replacement" portion of the project.

To order contract plans and special provisions call (916) 654-4490. As-built drawings are available for viewing through Mr. Yader Bermudez at (510) 286-5549.

14)Reference sheet 116 of 190 "PIERS 3 & 13 FOOTING RETROFIT DETAILS NO. 2." Note 7 states that "Whenever new concrete is to be placed against existing concrete, the existing concrete surface shall be roughened to 1/4" amplitude." Does this note also apply to Piers 4 through 12?

Note 7 applies to the details on this sheet, Piers 3 and 13.

15)Can the cofferdams at piers 3 and 13 be braced against the existing concrete structure? If so, what loads would be allowed?

Your attention is directed to Section 15 "Existing Highway Facilities"of the Standard Specifications.

16)The drawings indicate NGVD 1929 Datum. Please provide the elevations of Mean Sea Level, M.L.L.W., and M.H.H.W. at the bridge.

Check the following internet websites: National Weather Service: http://www.nws.mbay.net/marine.html, Office of Ocean and Earth Sciences: http://www.opsd.nos.noaa.gov/tides/westSF.htm

17)Please provide the elevations of the top of Piers 4 through 12.

The elevation for the rocker bearings is provided in the rocker bearing details in the As-built plans. The top of concrete pier elevation can be calculated from the rocker bearing elevation provided.

18)Can the Contractor work on more than one new drilled caisson at a time at any one pier foundation?

No restrictions are specified.

19)Reference 10-1.04 ENVIRONMENTALLY SENSITIVE AREA. Please define the limit of the "shoreline" (i.e. contour elevation).

All areas between the water line and contour elevation 40. The ESA area is also delineated on plan sheet 5 of 190.

20)May alternative methods of joint preparation such as a bonding agent be used in lieu of roughening the concrete?

Bid what is specified in the contract. Alternative construction methods would be reviewed after award of the contract. There is no guarantee of approval.

21)Regarding U.S. Coast Guard Letter # 16591, dated July 10, 1996, Paragraph 5. a)Please provide the time frame of winter-run chinook salmon. b)How does the contractor determine if construction will occur in an area involving the winter-run chinook salmon? c)What restrictions will be imposed upon the contractor so as not to impact the species? d)What are the methods of relief available to the contractor in terms of schedule, extended overhead, etc..

a) Winter season. b), c) & d)Construction operations confined within cofferdams should not impact the winter-run chinook salmon, therefore, no special requirements are specified in the permits nor construction delays are expected due to the winter-run chinook salmon.

22)Regarding Special provision 5-1.21, Relations with U.S. Army Corps of Engineers. Item #1- "All work performed within the Carquinez Strait in areas of 10' or less at Low Low Water shall occur only between December 1 and March 31 of the following year." Regarding Department of Army Letter File # 22066N. Item #1- "All work performed within the Carquinez Strait (in areas below 3 meters at mean Low Low Water) shall occur between December 1 and March 31." a) Please clarify the intent of the permit. b) What work operations will be controlled by this specification? c) Is the work inside the cofferdam or inside the existing footing considered to be "work performed within the Carquinez Strait" as specified in the above paragraph?d) Will work from a barge located in water with depth less than 10' or less at Low Low Water be prohibited by this specification

a) The intent of the permit is to do all work located in areas outside the cofferdams where the depth of the water is 10 feet or less at Low Low Water only between December 1 and March 31." b) All work outside of the cofferdam will be prohibited by this specification. c) Work within the cofferdam is OK between December 1 and March 31 period. However, cofferdams shall be built only during this time period. d) Barges could be setup in these areas as long as they remain floating. However, work from these barges will be restricted to work only within the cofferdams.

23)Regarding Regionwide Permit #RWP-9, Notice of Intent to Proceed #NOI-96-43, dated March 14, 1997, paragraph I. If a clapper rail nest is found, will the restricted area be limited to within a 500' radius of the nest or will include an area with a perimeter of 500' from the project boundary?

The restricted area will be limited to within a 500' radius of the nest.

24)Section 10-1.21 Piling Page 98 Section labeled "Construction", the second paragraph states, "The equipment used shall be capable of correcting the direction of drilling during the process of the work." We are not aware of any equipment capable of changing direction, only equipment capable of maintaining direction. Please provide a clarification on the statement and potentially a list of subcontractors capable of meeting this specification.

The following companies have the technology for "Directional Drilling" or MWD (Measure While Drilling)":

Tustin Ca.
Contact: Charles Ron Adams(714)259-7760
Christensen Drilling
Salt Lake City, Utah
Contact: Mike Harten(541)857-6892
Scientific Drilling
Houston, Texas
Contact: Pierre Bessiere(281)443-3300
Volkens Directional Drillers
Dyersville, Iowa(319)875-7011

25)>The jacking shoe on the truss shown on Sheet 90 & 92/190 does not line up with the bearing area of the Pier shown on Sheet 93/190. In fact the jacking point on the truss is offset from the area just as shown in the plan view. Considering the size of the loads to be jacked and the size of the jacks required, the jacks will block the installation of the masonry plate and the bearing assembly if located under the jacking shoe. It appears the jacking shoe on the truss needs to be located farther away from the center of the bearing. Please advise.

The details on contract plan sheet 93 of 190 correctly show the relative offset of the jacking point with respect to the bearing area. Your attention is directed to Section 10-1.19 C, "RAISE BRIDGE" of the special provisons. Per these provisions, design of jacking assemblies and supporting systems are the Contractors responsibility. SEE ADDENDUM No. 5 FOR NEW REVISIONS TO THESE SPECIFICATIONS.

26)Additionally the bearing area below the jacks does not appear to be of sufficient size to maintain the 1500 PSI bearing limit. Please advise.

Any portion of the top of pier may be used to distribute the jacking load as long as the specified maximum bearing pressure is not exceeded. Additionally the provisions in Section 10-1.19 C, "RAISE BRIDGE" state that alternative jacking procedures may also be proposed by the Contractor which will be subject to the approval of the Engineer. SEE ADDENDUM No. 5 FOR NEW REVISIONS TO THESE SPECIFICATIONS.

27)What is the purpose of the reaction block shown on sheet 93 / 190?

The reaction blocks are for bridge maintenance and may be used in the future to re-center displaced bearings.

28)The access openings in the existing concrete structures as indicated on the drawings are limited in comparison to the amount of work required inside the piers. Can additional access openings be made, particularly on top of Piers 3 &13?

The access opening locations shown on the contract plans are at locations of minimal service load stress concentration. Alternative access opening locations will be subject to review and approval by the Engineer after the bid opening.

29)It is possible that water will be encountered inside of the existing footings of Piers 4-12. How will the Contractor get paid for dewatering the cells?

Your attention is directed to the third paragraph in Section 51-1.05 "Forms", the last paragraph in Section 51-1.09, "Placing Concrete" and the second paragraph of Section 51-1.23, "Payment" of the Standard Specifications. SEE ADDENDUM No. 5 FOR NEW REVISIONS TO THESE SPECIFICATIONS.

30)Specification 10-1.25 "CURING" states that "the formed surfaces which will be exposed in the completed work shall be cured by the forms- in- place method." This method requires that the concrete forms remain in place for seven days. This adds a tremendous amount of time to an already tight schedule. Can an alternative curing method be permitted that would allow a shorter form stripping duration.

Alternative curing methods will be subject to review and approval by the Engineer after the bid opening. The forms in place method was selected for uniformity of appearance.

31)Section 5.1-34 requires two working boats be provided and operated for the duration of the contract. Will Caltrans require the boat operator and crew members for these boats to work a full ten hour day for each working day of the contract, including Saturday, Sundays, and holidays? Will the boat crews be required if the Contractor is not actually working a particular Saturday or Sunday?

The Contractor shall provide the boats and crews for every day that the Contractor is scheduled to work including Saturdays, Sundays, and Legal Holidays. SEE ADDENDUM No. 3 FOR NEW REVISIONS TO THESE SPECIFICATIONS.

32)Section 5-1.21, page 23, note 4, Temporary construction platforms of approximately 9,000 sf at Pier 3 and at Pier 13 will be required. Please confirm that these temporary platforms are permitted under the "temporary fill" definition, and allowed by the contract.

The area for temporary construction platforms shall not extend more than 50 feet in all directions from the existing foot pier, which would be within the center of the platform.

33)Special Provision 5-1.26, "Utilities," The contractor will not be permitted to use existing State utilities on the bridge or within the contract limits. Will the State owned compressed air lines be available for contractor use if contractor supplies the compressed air?


34)Reference specification 10-1.25 "CONCRETE STRUCTURES" which states that "The concrete for the new exterior and interior pier walls which are in contact with the existing concrete shall be placed at a rate not to exceed 4 vertical feet per hour, or in lifts not exceeding 15 feet in height. Such concrete shall be revibrated just prior to the initial set." Please clarify the revibration requirement.

Your attention is directed to Contract Addendum No. 1 dated December 23, 1997.

35)Reference Piers 4 through 12. Can the HS threaded rods in the lower 15 feet of the footing for cells 1 through 8 be drilled and installed after the grouted pipe pile installation? There is a potential for damage to the HS threaded rods, which are spaced at 24-inches on center, when drilling the 17-inch diameter pipe pile hole.

The high strength threaded rods referred to may be installed after installing the grouted pipe pile. Your attention is directed to Contract Addendum No. 1 dated December 23, 1997.

36)Regarding contract plan sheet 120 of 190 under Description of Bridge Work and Construction Sequence, step #5: "Construct upper reinforced concrete footing cap in cells 1 through 10 for piers 5 through 11 and cells 1 through 8 for piers 4 through 12. Strengthen walls in the remaining cells." Regarding section 51-1.13 "Bonding" of the the Standard Specifications: "When existing structures are to be modified, construction joints between new and existing concrete shall be cleaned and flushed as specified herein for horizontal joints." Surface prep for horizontal joints is desribed accordingly, "Abrasive blast methods shall be used to clean horizontal construction joints to the extent that clean aggregate is exposed." Question: For cells that are filled with concrete, what type of surface preparation of the existing concrete will be required, i.e. mechanical roughening, sandblast, high pressure water blast, or do nothing???

The requirements of Section 51-1.13 "Bonding" of the Standard Specifications apply. Additionally your attention is directed to Contract Addendum No. 1 dated December 23, 1997.

37)Please confirm the minimum intervals at which construction joints can be placed in pier 3 and 13 footings and extensions.

Only vertical construction joints shown in the plans are due to the sequence of partial bridge removal segments as shown on contract plan sheet 114 of 190. All other construction joint locations are subject to approval of the Engineer. SEE ADDENDUM No. 5 FOR NEW REVISIONS TO THESE SPECIFICATIONS.

38)To which pay items do the following belong: Jacking brackets at piers 3 & 13(which are turned over to the State at job end), Jacking brackets at pier 4...attached to posts, Bolts to fill open holes at removed jacking material @ piers 5 through 12.

Furnish and Erect Structural Steel (Bridge).

39)With reference to Special Provision 10-1.36 "STEEL STRUCTURES" , Page 136, last paragraph re:clause REPLACE FASTENERS.... There is numerous reference to blasting and painting requirements for new and existing contact surfaces and under bolt heads (replaced) and the above referenced clause specifies that cleaning and painting in accordance with the provisions of the specifications is required " before any existing adjacent fastener is removed". AASHTO spec specifies that coated joints shall not be asssembled before coating has cured for the minimum time used in quantifying the test. (This would typically be 16 - 24 hours depending upon the paint selected for use.) Please confirm if it is the intent of the specifications that there be a 16 - 24 hour wait between the removal and re-installation of adjacent fastners?

Bid what is in the contract plans and specifications. Additionally your attention is directed to Contract Addendum No. 3 dated January 12, 1998.

40)With reference to special provision 10-1.37 "CLEAN AND PAINT STRUCTURAL STEEL"on page 137, 3rd paragraph re: caulking of open seams.... Please clarify the definition of joints "that would retain moisture". Also, please confirm the approximate quantity (l-ft) of joints that you anticipate will have to be caulked.

The phrase "retain moisture" would apply to joints that would remain wet if subjected to precipitation or moisture in the environment. Caulking is included in the payment for "CLEAN AND PAINT STRUCTURAL STEEL" with no estimated quantity.

41)Does the surface of existing structural members covered by new reinforcing plates require the Dry Spot Blast and Undercoat?


42)Does the surface of existing gusset plates covered by new splice plates require the Dry Spot and Blast Undercoat?


43)Does the surface under the heads of bolts at the underside of connections require the Dry Spot and Blast and Undercoat?


44)With reference to Spec. Provisions section 10-1-25 [curing] please specify which formed surfaces are considered to be "exposed"! Is the "form in place curing method" applicable to all interior formed surfaces or only to the exterior formed surfaces?

"Exposed" refers to all external walls that are visible after the retrofit is complete. Bid it as you see it. Refer to section 90-7.03 "Curing Structures" of the Standard Specifications.

45)With reference to drawing #140 of 190 sheets, confirm that during construction of the cofferdam and the construction of the footing of Pier #3, the outer railroad track of the existing SPRR will not be used. If SPRR track must remain in service specify how cofferdam can be built.

Your attention is directed to Section 13 "RAILROAD RELATIONS AND INSURANCE" of the special provisions.

46)Section 10-1.21 "PILING" on page 98, monitoring system: The monitoring system shall be a down the hole system consisting of either ultrasonic, or magnetic, or horizontal drilling. Please supply us with name of subcontractor or supplier of the equipment.

There are Non Destructive Testing and Directional Drilling Contractors available through the Internet. Also see list from previous inquiry listed above

47)On contract plan Sheet 116 of 190, note #7, existing concrete to be roughened to 1/4" amplitude does this mean: a. 1/4" grooves into the concrete surface b. 1/2"grooves into the concrete surface

Your attention is directed to Contract Addendum No. 1 dated December 23, 1997.

48)In addition to our earlier questions: special provision section 10-1.01 paragraph 15 requires bonding of dowels in the pier walls during the same shift the drilling occurs. This requirement will not allow the pre-tying and placement of new wall steel in mats. But rather piece by piece in the air with these huge #14 bars. Is this really your intent?

The intent is to avoid "drilled holes" left open for an extended amount of time. Bid what is in the contract plans and specifications. Alternative construction methods are subject to approval of the Engineer after the bid opening.

49)Reference Specification 10-1.01"ORDER OF WORK; Can interior pier wall concrete work be completed before foundation retrofit is complete, where the vertical embedded #14 rebars for the new exterior pier walls would block off access to the interior pier wall access openings?

See contract Addendum No. 2 dated January 9, 1998.

50)Section G-G Sheet 135 shows an existing interior wall in the lower right portion of the detail. This is the only place the wall is shown. Please provide detail of the entire limits & locations of this wall.

Your attention is directed to Contract plan sheet 131 of 190 which shows the existing 12 inch +/- wall thickness. Additional details are available from the as-built drawings.


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