Invitation to Bid # CC Project Title: High Zone 5.0 Million Gallon Reinforced Concrete Culinary Water Tank Project No.

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1 Riverton City Purchasing Department South 1700 West Riverton, UT Fax: May 5, 2017 ADDENDUM #3 Invitation to Bid # CC Project Title: High Zone 5.0 Million Gallon Reinforced Concrete Culinary Water Tank Project No.: ENG-WA This Addendum shall be considered part of the Contract Documents and Specifications for the above-mentioned project, as though it had been issued at the same time and shall be incorporated integrally therein. Where provisions of the following supplementary data differ from those of the original Contract Documents and Specifications, the Addendum shall govern and take precedence. The following changes have been made to CC17-332: Addendum #2: Replace Item No. 6, Section Precast Concrete Fence of Addendum #2 in its entirety with the following Item No. 6: 6. Section Precast Concrete Fence: Paragraph 2.02 PRECAST CONCRETE FENCES: a. Delete Sub-Paragraph B ; barbed wire. Paragraph 3.05 PRECAST CONCRETE FENCE INSTALLATION: a. Delete Sub-Paragraph C ; barbed wire and accessories. DIVISION 13 SPECIAL CONSTRUCTION 1. Section Post Tensioned Concrete Tank Add Paragraph 2.2.E as follows: E. Tank design requirements: 1. Minimum final total wall thickness shall be 12 inches. 2. The cast-in-place tank core wall and roof shall be supported by solid neoprene bearing pads allowing free radial movement of the wall relative to the wall footing and the roof relative to the cast-inplace core wall. The walls shall be tied circumferentially to the wall footing with seismic cables consisting of hot-dip galvanized strands encased in closed cell sponge rubber sleeves. A shear connection allowing free radial movement of the roof relative to the cast-in-place core wall shall be included. A PVC waterstop connection shall be provided between wall and wall footing. 3. The minimum pad thickness between the cast-in-place tank core wall and the wall footing shall be 0.75 inch and between the roof and the core wall shall be 0.50 inch.

2 4. No reduction in ring compression or tension in the cast-in-place tank core wall will be taken due to restraint at the top or bottom. 5. Friction between wall and rubber bearing pads and lateral soil pressures shall not be considered in resisting seismically generated shear forces between the wall footing and the core wall or between the roof and the core wall. These forces shall be resisted by positive connections taking the loads in the tangential direction only and at the same time allowing free radial motion of the wall. 6. The tank designer shall use restraint cables to resist earthquake and/or wind loads at the wall to wall footing connection and restraint cables or steel shear cans at the wall to roof connection. Restraint cables shall be hot-dip galvanized seven-wire strand and shall be manufactured in accordance with ASTM A416 prior to galvanizing, and ASTM A475 after galvanizing. Only seven-wire strand will be allowed. 7. The wall circumferential and vertical prestressing systems shall offer complete two part epoxy protection of the prestressing steel inside ducting and anchors. Portland cement grout will not be accepted. 8. All prestressing/post tensioning steel in the tank floor, wall and roof shall be grouted. 9. All circumferential prestressing/post tensioning of tank walls shall be done with hot-dipped galvanized strand conforming to the material requirements in these Specifications. For multi-strand prestressing units, plastic spacers shall be used inside the duct at maximum 4-0 intervals to maintain separation between strands. 10. The interior columns shall have a minimum diameter of 18 inches. Columns shall be reinforced with spiral reinforcement per ACI , ADD Paragraph 3.1.E as follows: E. Wall: 1. The wall shall cast-in-place and have a minimum total final thickness of 12 inches and be poured without any horizontal joints. The wall design shall be such that wall sections can be poured full height without creating horizontal cold joints. Questions and Answer Sheet Attached and Incorporated Herein: DRAWINGS: 1. Drawing C.102 Proposed Site Plan: The scale of this drawing is 1 = 60 (not the 1 = 40 that is shown). 2. Drawing C.102A Grading Plan: The scale of this drawing is 1 = 60 (not the 1 = 40 that is shown). 3. Drawing D.114 Misc. Details: All line posts, pull posts, end posts, corner posts, tie rods, bracing, tension wires, gates, latches, truss rods, and all other appurtenances shall be black vinyl coated to match the black vinyl coating of the fabric. Fence diameters shall be as follows:

3 Line Posts: 2-3/8 End, Pull & Corner Posts: 2-7/8 Please acknowledge receipt of this addendum by signing, dating and sending back with the bid. Company Name: Signature: Date: If there are any questions regarding this addendum, or the overall project, contact the Riverton City Purchasing Agent, Craig Calvert: (801) , or Thanks, Craig Calvert

4 Bid #CC High Zone 5 Million Gallon Reinforced Concrete Water Tank Project May 2, 2017 Q. Is there an engineer s estimate for this project? A. No. Q. Can you clarify the required qualifications of the contactor? Q. Concrete specification requires a waterproofing admixture (Xypex or similar) for the concrete tank ( D.5.b.) Is this admixture required in the concrete for the post tensioned tank alternate design? A. Yes. Provide concrete as specified. Q. Is the EPDM membrane and perforated pipe under the tank floor required for the post tensioned tank alternate? A. Yes. Provide the EPDM membrane and perforated pipe underdrain system as shown and specified. Q. Bid item #15 calls out a 6 class 150 PVC pipe, while Plan Sheet C.109 detail 1 calls out perforated HDPE pipe around the tank and solid HDPE pipe as it leaves the tank. Which pipe type is it to be, and if HDPE, is ADS N12 smooth wall interior pipe the desired pipe? Also, the bid quantity calls for 170 of pipe while the plan sheet calls out 216 on each side of the tank with an additional quantity for the solid pipe leaving the tank. What quantities should we use? Q. Spec 2.01 D..ductile fittings & accessories shall be made in the USA..so I need some clarifications.. Does this mean the t head bolts & nuts on Mega lugs need to be made in the USA also (not standard) Do Flange bolt kits need to be made in USA? Do the DIP spools need to be made in USA? In the vault do the FCA s need to be USA? A. Yes, USA.

5 Q Sheet D.109.shows 6 drain line connecting to 20x6 tee..sheet c.105,,,,,,shows 6 drain line connecting to 20 overflow line.not sure which is correct..also where does the 4 floor drain line drain to cannot see location on plan where sump is located. Q. There seems to be discrepancies in regards to the rebar in the tank floor. On sheet D.101, it calls out the floor bar as #5 bar on 9 centers each way. On sheet D.106, it calls out that bar as #5 bar on 12 centers each way. Please clarify. Q. We are trying to do a grading takeoff as the bid items are Lump Sum but the plans block out all the contours running through the new tank. Can a CAD or separate sheet showing proposed and existing contours be provided so we can do an accurate takeoff? A. The CAD files have been posted on the purchasing website, link is below. CAD files are for bidding purposes only, field inspections are encouraged to bid correct quantities. Q. The plans call for 45 mil EPDM. Would it be acceptable to use PVC instead of the EPDM? A, No, bid as specified. This item may be considered as a value engineered item with the awarded contractor. Q. Drawing C.102 refers to drawings D.114 and D.115 for fence, gate and gate operator details. However, drawing D.114 isn t in the bid drawings and D.115 refers to pending vendor information. Will those drawings and operator related specifications be provided prior to bid date? A See Addendum 2. Q. There are no supplemental conditions as referenced in the specifications? A. See addendum 2. Q. Is onsite material testing being provided by the City? A. See Addendum 2, supplemental general conditions.

6 Q. Is all survey being provided by the City, or just control points? A. City provides Just control points. Q. In the bid items there are options for a conventional, wrapped and post tension options. How are the different tank options to be evaluated for award (lowest price, city preferred, etc) Q. Bid items call for 4 Asphalt around tanks, however Detail 1/D.112 indicates 3 AC over 6 RB. Q. Horizontal lap required for the #7 horizontals? A. 28. Q. Please verify lengths for the vertical & bottom hook for the #8 vertical wall dowels, each face? A. Bottom hook length is 32 vertical hook length is 43. Q. Which bar has a hook or are both the bottom and top hooked at ends, sheet D.101, section 2? A. Top bar hooked. Q. Please verify lengths for the vertical and bottom hook for the column vertical dowels? A. 30 horizontal and 41 vertical. Q. Which bar has a hook or are both the bottom and top hooked at ends, sheet D.103, section 6? A. Bottom bar hooked. Q. Please give the size and spacing of the bottom radial bar? A. #6, 12 on center, continuous, as shown on D101.

7 Q. Is there a building Permit required? If so from whom and who will pay for it? A. Yes, the City will pay for it. Q. Does the city have a export location for extra fill and temporary staging of backfill and materials? A. No, it is onsite. Q. The alternate tank design, pre stress and post tension are not required to be submitted, they are an alternate design if we chose to give you a price? A. Yes. Contractor may submit a bill on all items or choose to submit on only one, see additional instructions for bidders. Q. The plans on D.111 show SCAADA/RTU panel by others. On bid schedule Item 26 it calls for SCADA system to be furnished and installed as a line item. Which of these are correct? A. See addendum 2. Q. If the electrical contractor is required to provide SCADA who does the City use and are they aware of the project? A. The City has a contract for SCADA Services with NKD and they are aware of the project. Q. Which bid item includes the 45Mil EPDM liner for measurement and payment? A. It is included in 18, (18a, 18b or 18c whichever tank is being bid). Q. Bid item 21 Waterproofing to the exterior tank walls. Is there a Waterproofing Spec for this bid item or is it a damp proofing spec? Q. In the concrete spec, (H) is a damp proofing spec for the roof. Is this for the walls also, does the roof & walls get damp proofing in Bid Item 21?

8 Q. Ref: Detail 2/D.101: Would you allow a 90 degree angle for the formed edge on the drop panel per the detail in lieu of the 45 degree slope angle? A. Yes. Q. Please clarify Bid Item 22 Paint in Tank & Vault. What specifically gets painted in tank and vault? A. Paint just the valves and piping. Q. The supplier of the HMS mixing equipment has excluded any pipe support systems for their scope of work. Please provide a pipe support system/details and quantity required for the HMS mixing system. A. See addendum 2. May 5, 2017 Q. Precast Concrete Fence: Is the footing a continuous footing or spot footing for the posts? Is the fence designed to retain dirt? A. The precast concrete fence shall meet the requirements of Herriman City. It is not designed as a retaining wall, although no open spacing shall be allowed beneath the fence panels. Q. Is Section to accompany the bid? The instructions for bidders in the addendum ask for these same items within 2 calendar days of the Owner s request. A. Follow the Instructions to Bidders in the addendum. Each BIDDER must be prepared to submit the requested information within two calendar days of the OWNER s request. It is not a requirement to be attached to the bid, but shall be submitted once requested by OWNER. Q. We are only removing the existing valves not the pipe right? A. This question did not reference any drawing or specification section so it is impossible to determine what it is in reference to However, there are not any lengths of pipeline removal, outside of the incidental requirements associated with connecting to existing pipelines, as a part of this project.

9 Q. Will piles be required for temporary protection or is there enough room for a sloped protection? Will it be for the 2 homes or all the way across the east side? A. This is a means and methods question which each BIDDER should answer according to their own method of providing the required protection. The boundaries of protecting the site are required around the entire site and will likely vary depending on location. Q. Is there any information for the automated gates (Bid item 37)? A. See Addendum #2 Bid Schedule. There are no automated gates. Q. Is there an engineer s estimate for this project? A. Already answered. See first Q&A session. Q. Bid item 45 and 46 both have seed included in the description. Is it duplicated? A. Not duplicated. Bid items and quantities as listed. Q. Is xypex to be included in all concrete or just walls and floors? A. Already answered. See first Q&A session ALL concrete. Q. Is xypex required on the alternate tank types? A. Already answered. See first Q&A session. YES. Q. Any AISC, buy American, or other special criteria for the piping and steel? A. Already answered. See first Q&A session. American made. Q. Is the decorative fence to be engineered? A. Answered above. Fence to conform to Herriman City Standards.

10 Q. Section of the Contract Specifications requires a minimum concrete Strength of 5000 PSI for the circular concrete tank roof. It is our understanding that in addition to the reinforced concrete circular tank base option, an alternate concrete tank design may be considered. As in the design of all structured, variations in geometry and connection details can allow designer to use various material in more efficient ways. Please confirm that if concrete strengths noted in the alternate design documents meet all relevant design standards for such a structure, that a lower roof concrete strength of 4500 psi is acceptable. A. Bid as specified.