MARKET INTEL |
DOCUMENT

Pipestem Dam Spillway Modification Project Industry day notes.pdf

OVERVIEW

Original Source
Contract Opportunity
Related Agency
Date Originally Posted
Aug. 27, 2021, 9:48 a.m.
Type
.pdf
Size
0.57MB
Profiled People
None

DOCUMENT PREVIEW

EXTRACTED TEXT

Pipestem Dam Spillway Modification Project - Industry Day Notes
August 17, 2021, Notes by Bob Worden

1. During the project site visit, contractors were informed of the small arms shooting range
in the spillway channel. USACE indicated that the shooting range is no longer active.
Contractors were also informed that a separate contract will be awarded to remove and
properly dispose of any lead contaminated soil in the former shooting range.

2. During the project site visit, contractors were informed that wetland mitigation would

be performed through a wetland mitigation bank.

3. During the project site visit, contractors were informed that tree mitigation planting

would be required in the contact.

4. During the project site visit, a contractor asked what restrictions there would be for

work hours. USACE indicated that the standard 8 AM to 5 PM work hours would apply
except for RCC and soil cement placement which would require 24 hours 7 days a week
operation.

5. During the project site visit, USACE was ask about seasonal fluctuations in the reservoir.
USACE responded that typically the reservoir comes up in the spring from snow melt
and rainfall and typical declines over the summer to its lowest levels in the fall.
However, it was pointed out that higher reservoirs can happen anytime in the year
which was evidenced by the high reservoir in the fall of 2019.

6. During the briefing, contractors were made aware that no construction vehicles will be
permitted on the dam crest road. All construction equipment will access the site from
32nd Street SE.

7. During the project site visit, contractors were informed that the model airplane flying

facility in the spillway channel will be relocated by USACE.

8. During the project site visit, USACE was asked if project access would be shared with the
public. USACE indicated they didn’t think access would be shared with the public but
would double check with the Pipestem project office. Confirmation with USACE project
staff indicated that access would not be shared with the public.

9. During the project site visit, USACE discussed a restriction of not allowing excavation in
the spillway channel (downstream of the spillway crest to the proposed weir) until the
stilling basin, chute structure, all walls and partial construction of the left and right dikes
were completed. USACE indicated that this restriction is so that the frequency of flow
through the spillway channel is not increased beyond that of the existing spillway
configuration.

10. During the project site visit, USACE was asked what water source could be used for RCC
and Soil cement batching. USACE indicated reservoir water, ground water or county
water supply could be used.

11. During the project site visit, USACE was ask if there were any Archaeologic issues for the
project site. UASCE indicated that an Archaeological investigation was conducted and
did not find any physical evidence of any Archaeologic remains. USACE indicated that if

any remains were uncovered during excavation, then an USACE Archaeologist would
need to evaluate the site at that time.

12. During the project site visit, USACE discussed the house located near the project access
just off of 32nd street SE. USACE indicated that there will be some requirements in the
contract for dust control.

13. During the project site visit, USACE explained that dewatering would be performance

based. USACE further explained that piezometers would have to show that the
dewatering system has adequately drawn down the groundwater below specified levels
and surfaces before excavation to that level.

14. During the project site visit, USACE was asked what utilities existed along 32nd Street SE.
USACE indicated that they did not know, but the contract existing conditions drawing
would identify the utilities that exist.

15. During the project site visit, USACE was ask if the contractor would be responsible for
permitting. USACE indicated that yes that the contractor would be responsible for any
permitting.

16. During the project site visit, USACE ask if there would be any restrictions for power

generators. USACE indicated there would be no restrictions.

17. During the project site visit, USACE was ask if the piezometers and pumping wells would

be protected or removed. USACE indicated piezometers and pumping wells in the
footprint would be removed and others outside the footprint would be protected.
USACE indicated that the contract plans will show which are to be removed and which
are to be protected.

18. During the project site visit, USACE indicated that the contractor’s QA lab would need to

be certified.

19. During the project site visit, USACE indicated there was a load restriction sign on 32nd

Street approximately 0.5 mile east of the 8’ x 8’ twin box culverts. A photo of the sign is
provided below. It was noted after Industry Day that there is no load restriction sign
west of the box culverts on 32nd street SE. USACE will check with Stutsman county to
see if the sign is old and no longer valid or is still valid.

20. During the briefing, USACE was asked to explain how the reservoir level may impact the
ground water. USACE explained that ground water levels in the Glacial Fluvial Sands
were responsive to reservoir levels. USACE also indicated that water levels in the Shale
have a less (more muted) response to reservoir levels.

21. During the briefing, USACE was ask about rough order magnitude of quantities for

excavation, fill, RCC, soil cement, reinforced concrete, riprap, spalls, and bedding. The
following rough order quantities were provided. USACE stressed that many of the
quantities were from the 65% design and all were subject to change.

Excavation - 1,700,000 cy
Fill - 1,300,000 cy
RCC - 70,000 cy
Soil Cement – 50,000
Structural Concrete – 15,000 cy (may increase up to 25,000 Cy with recent design
changes)
Riprap – 10,000 tons
Spalls – 4,000 tons
Bedding – 4,000 tons

22. During the briefing, USACE was ask whether the USACE designed cofferdam along

Pipestem Creek would have a cutoff. USACE responded that the current design has no
cutoff for the cofferdam. USACE further stated that any changes in cutoff requirements
would be based on future seepage analyses.

23. During the briefing, contractors were made aware that the dewatering design would be

the responsibility of the contractor.

24. During the briefing, contractors were made aware that the mix design for the RCC and
soil cement will be the responsibility of the contractor. Contractors were informed that

the mix designs will be performance based. Contractors were told that for the current
design the required RCC compressive strength is 4000 psi at 90 days and for soil cement
required compressive strength is 875 psi at 28 days. The contractor was informed that
these compressive strengths are subject to change.

25. During the briefing, the contractors were informed that the design is currently between
65% and 95% phase and that all information presented in the PowerPoint relating to the
Spillway Modification Project are subject to change.