Site_Visit_Q&A.pdf

GA NDT Spillway Gates Questions:

1. Do you have any supporting photos of the spillway gates?

* Filled erection bolt holes

* Trunnion

* Anchor bolts

* What are the weld locations for PAUT and UT for the 8 gate arms?

A: There are three sheets of photos in the project plans for a total of 24 photos that are applicable to the project.

2. Where do you want the strain gauges placed?

* I know the purpose is to determine the stress on the end frames and horizontal girders. But still unsure which locations you would like us to place them.

A: The field erection bolts and plug welds can be found on photos A2 and A3 of sheet G‐006.

3. How many strain gauges do you want to use on gate 5?

A: Trunnion photos can be found on sheet G‐005.

4. Do you have photos or information on the highway we will be working on?

* How high is the highway above the spillway gates?

* What is the layout of the lanes of the road?

A: Trunnion anchor beams can be found on sheet G‐005

5. Do you have an approximate footage of welds that need the paint removed or any information on the number of welds that need paint removed?

A: Refer to sheets S‐102 and S‐103 for trunnion arm weld testing locations.

6. In lieu of containing each testing location, would the USACE allow the use of wet abrasive blasting to prepare surfaces? This would be more cost effective and shorten durations needed to complete testing.

A: Refer to the S‐100 sheets for descriptions and locations of MT locations.

7. Specification 09 97 02 calls for full containment per SSPC class 3A of the areas to be abrasive blasted in paragraph 1.2.3.2. The specification also calls for visible emissions monitoring during the surface preparation in paragraph 1.2.3.3. Please consider modifying paragraph

A: Refer to the S‐100 sheets for descriptions and locations of UT locations

8. 1.2.3.2 to allow for wet abrasive blasting without containment and eliminate the visible emissions monitoring requirement in paragraph 1.2.3.3 as the wet abrasive blasting eliminates fugitive emissions. The areas requiring abrasive blasting are small and are spread out through the 28 gate spillway structure. The time to perform the containment work would exceed the time it would take to perform the work.

A: Refer to sheet S‐106 for strain gauge test locations

9. How many strain gauges do you want to use on gate 5?

A: Refer to sheet S‐106 for the number of strain gauges to be used

10. How many linear feet of weld need paint removed?

A: Estimation of linear weld paint to be removed can be made by using the contract drawings.

11. Do you anticipate the small business set aside for the above reference solicitation to be removed?

A: This requirement will remain a 100% small business set‐aside

12. How long will each operation cycle last?

A: the operation cycle duration will vary greatly depending if the Contractor decides to allow the gate to be loaded by natural stoplog leakage, pumping, or requesting the Government to remove and reset the top stoplog. Loading the gate by natural leakage would depend on the ability for the stoplogs to seal, and could vary in length from several minutes to several hours. Loading the gate by pumping could be estimated by calculating the filling rate of the pump unit. Requesting the Government to raise and then lower the top stoplog would require coordination efforts and may not be as consistent as the other options, especially if there are any operational malfunctions or delays. Once the gate/gauges have been loaded, it is estimated that the time to operate the gate 6", allow the water to drain out, and lower the gate to the sill would take 2 to 5 minutes if there are no operational delays."