Attach 5 Addenda.pdf

Mount Rushmore National Memorial Renovate Existing Water Storage Tanks

Specification Addenda

1. The NPS anticipates this project to begin approximately July 15, 2021. See block 10 of the 1442.

2. Hatch modifications on the 75K tank and the 125K tank include one on the 125K tank and the 75K tank has two access hatches and one valve vault access hatch to modify. The 500k reservoir existing hatches will remain.

3. Contractor may propose the use of a helicopter in remote locations if motorized conveyance is unable to reach a site. No special permits are necessary, however, the dates, times, and number of flights must be reviewed and approved by the Park BEFORE flights are allowed in Memorial airspace. In general, if helicopters are used, the airship company will be required to file plans with the FAA, and the park will dictate times the flights can happen. Flights will not be allowed to fly over people or buildings, because of park visitation, earliest morning flights possible will be required. The Park does not have a Point of Contact for a helicopter company.

4. Spec Section 01 11 00 1.4 B. Storage of Materials: The contractor may store equipment near site as long as the equipment is away from the trail and does not interfere with trail access by visitors. The Park will work with the selected contractor for appropriate areas for storage, construction trailer and material laydown.

5. Spec Section 01 11 00 1.4 B. Storage of Materials: Materials shall be stored at the location of both the 125K and 75K storage tanks, storage heavy equipment on top of the concrete tanks is not allowed. The Park will work with the contractor on alternative storage areas for heavy equipment. Some lighter equipment may be stored on top of the tanks with weights not exceeding 2500 lbs. weight limit.

6. Spec Section 09 96 00 3.2 D Concrete Surfaces: The product type used on the existing tanks was a two-part system; Pota-Pox (Fast Cure) Series FC20 and Elasto-Shield Series 264. Both are Tnemec products. The date of these material applications was 1999 and the Park is not aware of the thickness of material coats.

7. Records of repairs completed on each tank in the past are not available.

8. The Park will provide snow removal for access to the 500K tank. Snow removal from the top of all tanks will be the responsibility of the contractor.

9. Electrical information pertaining to the 75K tank: Voltage is 240 volt and existing wire is size 8 gauge. The wire manufacture specs for the probe are: Cat no. 6013-W6 and part no. 13-024300, B/W Controls. The information that comes with the probes states the wire type connecting to probe. Follow manufacturers recommendations and specifications on seal tight conduits. All cables are to be installed on the ground.

Specification Addenda

10. Onsite utilities available for the 75K tank includes 120-volt power but no potable water. There are no onsite utilities available at the 125K tank. There is 120-volt power and potable water available at the 500K tank. Contractor is responsible for providing their own portable toilets.

11. For 75K Gal tank: Replace the existing ladder and replace the existing rungs. Field verify and match existing fiberglass ladder dimensions.

12. The diameter dimensions of the inlets to the three reservoirs are as follows: 75K tank is 6-inch.

125K is 6-inch. 500K is 4-inch

13. The water tanks at Mount Rushmore contain no lead-based coating systems.

14. Hydro-blasting water will be filtered and released through the tank drains.

a. Filter and release are acceptable. The filter process to be approved by NPS prior to discharge.

15. No manufacturer’s representative required to inspect preparation for each tank/surface or

a. application. NPS will inspect.

16. Alternative products will be considered and can be evaluated during the submittal process.

17. Spec Section 01 11 00 1.8 A. Work Restrictions: During coating applications, work hours may be extended to all daylight hours and including weekends. These extended hours must be approved by the CO on a weekly basis and in writing.

18. Spec Section 33 01 00 3.4 Reservoir Disinfection: 150 gallons per minute is available to fill and flush the three tanks.

19. Spec Section 22 05 00: Use existing pipe sleeves in all three tanks for replacement of pipes through existing walls.

20. The contractor is responsible for field verifying all the flanges on the piping repairs are standard 125# drilling.

21. Spec Section 03 30 00 Cast in place concrete: Follow the specifications as they pertain to installer qualifications. NPS will consider “qualified installed with at least 3 years of documented experience in forming & placing structural concrete”. NPS will consider “a pre-mix sack concrete containing a pre-determined mix strength is allowed to be mixed at the site at the time of placement in place of a concrete mix from a ‘ready mixed concrete production facility’”.

Specification Addenda

22. All three tanks are confined spaces and confined space requirements must be adhered to. It is the contractor’s responsibility to follow all OSHA regulations and requirements pertaining to confined space safety. Air exchange requirements based on confined space requirements must be adhered to. See OSHA requirements for confined space safety

23. The NPS will drain the three tanks.