Addendum 1 _ RFB 2024 _ 06.pdf

RFP NUMBER

2024 ‐ 06

Revere Drive Groundwater Well Addendum 1 ‐ Q/A

January 12, 2024

For any further questions about this RFP addendum contact:

Martyn Detz, Purchasing Coordinator

770‐592‐6000 Ext 1205 or Vendor Registry

Please note the following responses, clarifications and/or additional information for the above titled RFP with the appropriate sections listed for reference where applicable. City responses are in Bold text.

Questions

1. Specification 02830, 2.09 calls for two strands of barbed wire but Sheet 12 calls for three strands. Which is correct?

a. 3

2. Sheet 12 shows a fence detail with two swing gates at 9’ each, however Sheet 3 shows two gate locations with symbols depicting limits of the gate. One gate North of building scales to ~6’ (assuming one swinging gate), and one gate South of the building scales to ~10’ (assuming two swinging gates 5’ each). Please clarify fence gate requirements.

a. Single swing gate at the north pedestrian entrance, and a double swing gate at the south overhead door entrance.

3. Sheet 12 fence detail calls for privacy slats but these are not listed in the Specification 02830.

Are privacy slats required? If so are they required along the entire fence and gates? If so please provide product information.

a. Privacy slats are not required unless otherwise requested by the City.

4. Sheet 13 shows 3” DIP vertically in the well (Well Casing Stub Up Detail), but Sheet 6, Note 6 calls for Well Drop Pipe to be Threaded Galvanized Steel. Other parts of the documents mention threaded pipe. Please confirm the Well Drop Pipe is Galvanized Steel.

a. Confirmed. Galvanized steel.

5. Specification 02660, 2.01 Ductile Iron Pipe doesn’t discuss restraint. Sheet 3 requires using 2 ½” rods for the 16” DIP. Please confirm the following: a. 4” DI MJ Fittings should be provided with Wedge Action Restraints (Megalugs or equal)? Yes. b. 4” DI pipe joints should be restrained (factory restrained or other restraint method)? 4” pipe joints need not be restrained where the ends or bends are properly and independently restrained such that the is no tensile (uncoupling) force is on the pipe run. Otherwise, the entire pipe run will need to be restrained. c. 16” DIP should be MJ fittings with standard MJ accessories and (2) ½” SS rods? Yes. d. 16” DI pipe joints are push joint (unrestrained)? Yes. But, same provision as with the 4”. If proper thrust blocking at the fittings and transition points, or if there is any question regarding the adequacy of the thrust blocking, then full restraint on all pipe joints. e. Sheet 10, Rodding Restraint Detail calls for “SS” Rods. Is this Stainless Steel, and if so what grade? Note that 02660 3.07 F. calls for galvanized or bituminous coated. SS = stainless steel. Either 304 or 316, or equal. The intent is to provide double protection at all bends: Proper thrust blocking and rods. f. Do the (2) ½” SS rods span across the entire length of 16” pipe (spanning over 16” pipe joints and using rod couplers)? No pipe rods needed for straight pipe runs if thrust blocking/restraints at the bends and transition points is adequate. Use tables on sheet 12. The biggest question regarding thrust blocking is the adequacy of the bearing soil. If the trench is over-excavated and solid backing is unavailable, then additional restraints will be required. Fill dirt is not acceptable backing soil. g. Would restrained joint pipe and fittings restrained by wedge action restraints be acceptable instead of thrust blocks and threaded rod? Yes, if the alternative restraints are equivalent to the rods (as determined by approved submittal) and thrust blocking is included and adequate.

6. Sheet 12, Thrust Blocking Sheet 4 of 4 provides thrust blocks based on 150 PSI. Specification 02660, 3.10 calls for 150 PSI Test pressure, but Sheet 10 Rodding Restraint Detail lists 250 PSI Test Pressure. Please confirm test pressure is 150 PSI. If not please revise or confirm thrust block details are still appropriate.

a. 150 psi test pressure.

7. Sheet 12, Thrust Blocking Sheet 4 of 4, Note 2 states “The water line must be lowered in order to have five feet (5’) of cover at the bend, tee, reducer or plug at all locations where these fittings may be utilized”. Please confirm this note is not applicable to this project as Specification 02660, 3.01 requires 48” of cover.

a. Confirmed. 4 feet of cover is adequate.

8. Sheet 12, Thrust Blocking Sheet 4 of 4, Note 3 states “The contractor has the option to use restrained joints in lieu of or in addition to concrete blocking as specified in section 02660 of the specifications” but the specifications are silent on restraint, and Sheet 6, Note 4 states “Thrust Blocking Required At All Bends”. Please confirm if restrained joints are provided the thrust blocks and rodding are not required.

a. All bends and transitions require both restraint and trust blocking.

9. In 2.0 Scope of Work, paragraph 2.2 states “On Site testing of the soil compaction is required.” The documents don’t discuss who pays for this testing. It is standard for the Owner to pay for third party testing of soils, concrete, masonry, etc. Please confirm testing (including soil, concrete, and masonry) will be paid for by the Owner.

a. Owner will pay.

10. Drawing 6 & 7 have no scale or dimensions. Please provide a scaled drawings or dimensions on the drawings to determine the scale.

a. The building is 15 ft x 20 ft out-to-out (See sheet 3). The dimensions if printed on 11x17 is 1”= 3 ft. Unless otherwise specified, dimensions are generally not shown for plumbing flexibility and will be further addressed as necessary during the submittal phase.

11. Sheet 3 calls for a 15’x20’ well house. Since the drawings are not scaled is the foundation slab size 15’x20’, or is that the outside wall dimensions, or inside wall dimensions?

a. Outside.

12. The drawings are unclear on the buildings material of construction. Sheet 13 has both 2x4 Stud Wall and CMU Wall details. Sheet 14 shows the well head roof framing plan with CMU called out. Please confirm the Well House is the 2x4 Stud Wall Construction Detail, and the Well Shed is the CMU Wall Construction Detail. If not please clarify.

a. Confirmed.

13. Sheet 3 calls out “2” DIP Drain to Daylight (Bottom of 16” Pipe)” and “2” DIP Blowoff to Daylight”. a. 2” DIP is not made, (BHP International: Ductile Iron Pipe supplier and manufacturer for 15 years. We are expert of ductile iron pipe. Supply all sizes of DI Pipes like 2 3 4 6 8 inch ductile iron pipe for the municipal water and wastewater distribution) what material should be used? Submit an alternative material if you can’t get DIP. b. The note says “drain to daylight” (and “to daylight”), however the pipe doesn’t appear to be long enough to daylight based on pipe depth and grade contours. Specification 02660, 3.01 requires the cover of the 16” pipe to be 48” making the invert ~65” deep. Average finished grade elevation is 876, so invert ~870.58, but the end of the drain/blow off pipes are around EL 875. Daylighting the pipes are outside the limits of disturbance. Should the 16” Pipe depth of cover be reduced to allow the drain pipe to daylight, if so to what? If not please provide direction on how to address the drain elevations and daylighting issue (possibly consider removing to daylight requirement and providing different detail at end of pipe to allow a temporary submersible pump to be used when draining is needed since likely infrequent).

Good point and good idea. The drain pipe can go to a vertical piece of the 16” DIP or

PVC.

14. Sheet 10, the top of the page “Pipe Support” detail requires 1/8” thick insulation material, but this will require custom U-bolts due to the non-standard pipe OD. It is uncommon to install an insulation material on Ductile or Steel pipe (typically only used for copper pipe to provide dielectric barrier). Please confirm the insulation material is not required to avoid unnecessary additional cost and lead times.

a. This is a standard detail that is not used on this project. All exposed piping will be inside one of the two heated buildings.

15. Sheet 7 has a note “Chemical Line” but points to a blank area. Please clarify if additional chemical piping is required that is not shown.

a. That is for the chlorine feed line shown on sheets 6 and 7.

16. Sheet 7 has a note “Chlorine Injector (See Note 16)”, and “Chlorine Analyzed Intake (Note 18) but there are no notes on this drawing. Please provide missing notes.

16. CHEMICAL INJECTION QUILLS SHALL BE DESIGNED FOR CHLORINE. BODY,

SPRING AND BALL MATERIAL TO BE HASTELLOY C276.

18. CHLORINE ANALYZER CONNECTION TO BE PROVIDED AS FAR AS POSSIBLE

FROM WELL INTAKE IN HORIZONTAL DIP LINE. PROVIDE 1" TAP FOR

CONNECTION.

17. Please confirm the chemical tanks size, material, and concentrations as they vary from drawing to drawing. Sheet 15 mentions polyethylene, is this for all chemical tanks? Sheet 7 mentions drums. Is the contractor to supply all the chemicals? Owner may want to consider using chemical totes instead as these can be moved by pallet jack and exchanged easily through roll up door. a. 2 EA – 30 Gallon Chlorine (12.5% Sodium Hypo) b. 1 EA – 100 Gallon Fluoride c. 1 EA – 50 Gallon Caustic.

a. These will be the standard plastic drums for the chemicals specified as delivered by the chemical supplier. The first drums (2) for chlorine are provided by the contractor. Check with City for City’s usual supplier.

We use Hubbard Hall as our current chemical provider. Chlorine is 12.5% and supplied in 55 gallon drums.

18. Sheet 6 only shows the Chlorine tanks connected to the piping. Are the Fluoride and Caustic for use by the Owner as needed (used manually). Note that Specification 01025, 3.06 mentions chemical feed system for Sodium Hypochlorite and Fluoride), and no chemical feed is shown for Fluoride. Please confirm drawings are accurate and no piping or pumps are needed for Fluoride and Caustic.

a. Correct. Fluoride and Caustic are future potential needs as determined by the City. Fluoride and Caustic and Not included in the Contract.

Fluoride and Caustic will be needed at this well site. Please provide 2 additional ½” NPT taps downstream of Chlorine injection location. City will provide feed tanks/chemical pumps for any additional treatment beyond Chlorine.

19. Sheet 6, Note 13 calls for 1” PVC pipe to be installed along pump column for level transducer installation. Sheet 13, Well Casing Stub Up Detail shows a ¾” PVC pipe extending down into the well. Sheet 11 shows a wire and associated level transmitter but no conduit. Please confirm when the conduit terminates.

a. See sheet 11.

20. The Bid Form includes item #7 “SMART System”, however there is nothing in the documents to determine the scope of this work. Please provide drawings or specification on this scope.

The City is providing the necessary SMART system for this well to match our other wells. This needs to be redacted from the pricing sheet. This is referring to Multismart Scada System While our pumpstations have this technology the wells do not.

21. Specification 01025, 3.10 Access Drive states the access driveway/parking is GAB/crushed stone over the 16” pipe area. The limits of the stone are unclear, is the GAB/crushed stone to extend from back of curb (Revere Drive) to the Western edge of the Well Shed, and from 16” C/L to C/L in North/South direction? Please clarify intended limits. Please also clarify that Specification 02510 Asphalt Pavement and 02520 Concrete Paving are not applicable on this project.

a. The GAB/crushed stone limits are shown by the light line on sheets 3 and 4 (basically over the 16” pipe connecting to the street).

22. Sheet 6 calls out a 4’x4’ Concrete Landing. Sheet 3 also appears to depict a larger concrete landing South of the Well House (at roll up door). Is a concrete landing required at the roll up door per size scaled on Sheet 3? What are the concrete landing requirements (6” thick with WWF reinforcing?)

a. The landing at the rollup door would serve as a ramp. The edge at the door would be flush with the door threshold; the edge opposite the door would be flush with grade. 6” thick with WWF reinforcing. 10’W x 6’L.

23. 180 Days project duration will be difficult due to some material lead times being 12-16 weeks. Please consider revising the project duration to at least 270 days. It is possible named suppliers may have longer lead times which may require an even longer project duration than requested, but it is unknown at this time if that will happen. Please note that in the Bid Proposal Form on the page with the LUMP SUM ALLOWANCE AMOUNTS, 150 days is listed which is in conflict in earlier pages of the Bid Proposal Form.

City provide. We typically allow for delivery time delays if properly documented by the contractor.

24. Is there any specification or parameters required for the Silent Check Valve or Diaphragm

SSI Silent Check Valve: Single Flow, Inline Silent, Cast Iron, 4 in Pipe/Tube Size, Flange x Flange

Item

1RXG5

Mfr. Model

0400-125WCITM-T

Product Details Catalog Page

Brand

SSI

Manufacturer Part Number

0400-125WCITM-T

Item - Check Valves

Check Valve Flow Design

Single Mechanism and Body Design

Inline Silent Body Material - Valves

Cast Iron Pipe or Tube Size

4 in Connection Type

Flange x Flange Mounting Orientation

Horizontal; Vertical Seal Material

Metal Max. Temp. - Valves

300 °F Min. Temp. - Valves

60 °F Max. Water Pressure - Valves

200 psi @ 250°F Max. Steam Pressure - Valves

200 psi WSP Seat Material

Stainless Steel Spring Material

Stainless Steel Flow - Valves

1,000 gpm Full Flow - Valves

Yes Application - Valves

Process Piping Length

6-7/8 in

Width 4 in

Overall Height 6-7/8 in

Standards ASME Sec VIII and API598

Valve Body Material Cast Iron

UNSPSC

40141634

Country of Origin China (subject to change)

Product Description

Cast iron check valves have heavy-duty bodies that withstand high tem peratures.

4" Hayward DAB Series PVC Diaphragm Valve W/Flanged Ends, O-Rings

SKU:DAB1040FEK

Color:Gray 4" Hayward DAB Series PVC Diaphragm Valve w/Flanged ends, O-rings $1,411.99 Quantity Add to Cart

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DETAILS

The DAB Series Diaphragm Valves are available in sizes 1/2 inch to 6 inch, with PVC, CPVC, PP and PVDF materials. Possible end connections are true-union socket or threaded and flanged ends. All DAB Series feature a highly visable beacon indicator.

Possible diaphragm materials are EPDM, FPM and PTFE. PVDF vapor barrier available upon request for EPDM and PTFE diaphragms. The DAB Series are also available with pneumatic or electric actuation.

ADDITIONAL INFORMATION

MPN DAB1040FEK

Inventory Type DS Manufacturer Hayward Type Flow Control Valve Series DAB Series Valve Type Diaphragm Back Pressure Valve Valve Size 4" Valve Connection Type Flanged Diaphragm Material EPDM Material PVC Seal Type Double O-Ring Stem Max Pressure 150 PSI (10.3 bar) @ 70˚F (21˚C) Carton Qty 1 UPC Code 0610377085588 Color Gray Installation Manual Hayward DAB1040FEK Installation Manual Technical Data Hayward DAB1040FEK Technical Data

25. Sheet 6 calls for 2” DIP (which is not made) and 6” HDPE, but Sheet 3 calls for 6" to be PVC.

Please confirm both 2" and 6" pipes can be PVC.

a. PVC is okay.

26. Specification 02200, 3.10 requires general fills and backfill to be compacted to 95%, however it goes on to say “Cut areas shall have the top six (6) inches of material proof rolled and compacted to 100% of maximum density. Fill areas shall have the top twelve (12) inches proof rolled and compacted to 100% of maximum density.” It is uncommon to require compaction of 100% except for special circumstances. Requiring 100% compaction on cuts will likely require extensive work to the existing soil which will greatly increase cost and schedule duration (extremely unlikely any existing onsite soils are 100% compaction).

Requiring 100% compaction on fills for the top 12” would not allow for grassing and greatly increase cost and schedule duration. Sheet 4, Note 6 is a more appropriate/typical backfill requirement. Please confirm the 100% compaction requirement is not required on this project, and cuts do not require compaction. It is typical that if a cut’s subgrade is not sufficient or is unsuitable it is over excavated under the direction of the Engineer (or Geotechnical Engineer) and paid as a change order/allowance. Please confirm if this is how existing soil/subgrades will be handled.

a. See Class IV detail on sheet 12. Only other compaction requirement is any fill needed beneath the buildings. Utilization of incompressible fill (i.e. stone) may be substituted for earth fill. Typically, for any needed fill beneath the buildings, crushed stone is used.

27. I see no allowable manufacturer for a chemical feed system as a whole. I also do not see allowable manufacturers for components of one should the intent be that we are building one within the building by way of holding tanks and pumps. Please clarify the intent and where I can find allowable manufactures for this portion of the job. Please clarify the chemicals to be used for this portion of the work as well, as the specs read in a contradictory manner.

City provide. You can pick. You will probably want to use the same as you have in the other wells. Mike can help with this item.

Lutz‐Jesco MAGDOS LD 1 Chlorine feed pump with chlorine degassing head.