Lower Mud River FRM Industry Day Questions.pdf

Lower Mud River Flood Risk Management Project Milton, WV

Industry Day Questions

ACQUISITION STRATEGY/CONTRACTING:

• How would use of base and options impact your proposals? What features are critical or non-critical for base? What efficiencies are needed to reduce cost or improve production in base and option work?

• What specific data/information, if any, would you suggest be supplied to prepare a more competitive proposal?

• If base and options are considered, what features could be separated into an option while minimizing the construction risk?

CONSTRUCTION:

• How long do you estimate it would take to complete construction for this project? What do feel is a reasonable period of performance?

• What are thoughts on potential construction sequencing of major project features?

• What assumptions would you make for winter months regarding continued construction?

• What information should the Government provide for you to assess the risk of working in a floodplain?

• What are the areas of risk that you currently see in the design?

COST/SCHEDULE:

• Based on your experience, what information would improve your proposal and reduce construction risk?

• What are your proposed working hours for a regular work week?

• How would account for high water events in your project schedule and in your proposal?

How would you plan to minimize impacts from localized flooding?

• Are there any products that you would anticipate having significantly long lead times or difficulty acquiring? Are there any economic factors we may be unaware of that would impact construction cost & schedule? Factors such as availability of materials, equipment, testing, certifications such alkali aggregate certification, etc. (inflation, supply chain issues, labor uncertainty?

CUTOFF WALL:

• In past projects with cutoff walls, how have you determined top of rock?

• How would your team monitor the quality of cut-off wall installation, in terms of wall geometry and backfill material?

• What type of method(s) would you consider for construction of the cutoff wall?

• For your considered methods, what geometric restrictions can be expected? (e.g. radius of curvature, depth restrictions near alignment limits, clearance limitations, etc)

• Are your methods sensitive to water source or water quality (e.g. potable water, river water)? What is the typical rate of water usage for your cut-off wall installation?

• What is your required site areas for the cutoff wall installation? Do you feel that adequate area is provided within the CWL for mixing of cutoff backfill material? What methods would your team use to mix the backfill material?

• If soil-bentonite wall is selected, what means/methods would you propose to bridge between the barrier and the levee clay fill to allow for adequate compaction of the levee?

• The culverts through the levee are cast-in-place and will be constructed prior to the levee. How might you sequence the construction of the cutoff beneath culverts and the adjacent levee?

• How is your proposed methodology impacted by minimum/maximum strength limitations? What are the typical barrier strengths used with your means/methods?

• How would you handle disposal of waste materials, if any (i.e. slurry, mix constituents, etc.)?

DATA MANAGEMENT:

• In past projects, has your team employed data management systems to track test results? What has worked well? What has been challenging?

DEWATERING:

• What dewatering methods have been most effective in previous projects with similar foundation materials?

• Depth to rock in the area is shallow (approximately 6’) in the area of the new low flow weir. For construction of the low flow weir and raw water intake, what method of dewatering and temporary construction features do you feel are needed to build the features in the river?

• Concrete work will be required at/near/below the water table. What means/methods have been successful for your team with this type of work? What means/methods will your team propose?

EARTHWORK:

• Describe your earthwork sequence. Project excavation and borrow sites utilization. Will impervious material obtained from project excavation such as channel work and random excavation be used to the construct levee? What order do you propose for using the borrow/spoil areas? Will all borrow sites be used?

ENVIRONMENTAL:

• Tree clearing is only allowed during certain times of the year. How will that affect your construction schedule and sequencing?

• Sheetpile and H-pile will be driven for the T-walls and other structural features in close proximity to structures. How would you mitigate noise impacts from driving piles near residential and commercial structures?

• Have you had previous experience with pile driving in close proximity to residences and businesses?

GENERAL CONSTRUCTION:

• How do you propose minimizing impacts to the schedule due to weather? Consider impacts to: earthwork, levee construction, concrete work, cutoff wall construction, etc.

What activities would you anticipate completing over the winter?

• The pump stations are large structures with a deep excavation adjacent to the levee alignment. How will you approach the dewatering? Approach the mass concrete?

• Anything else we should know or your team wishes to discuss?

• How would you propose to dewater the existing sewage lagoons and prepare them for soil placement and how long do you estimate this would take?

RELOCATED CHANNEL:

• How would you propose to reduce downstream sedimentation when the relocated channel is connected to the existing river?

• How would you accomplish keeping the relocated channel free from flow for a growing season? What impacts would this create for sequencing and construction schedule?

SAFETY:

• How will you approach maintenance of traffic with access points and routing between various site areas?

• The project is in a populated downtown area with several deep excavations. How do you anticipate handling site security and safety?

SEQUENCING:

• Are the provided CWLs sufficient for the work proposed? Are there any limitations that would impact sequencing?

• With the CWL that has been provided, do you have any site access concerns? Any limitations with getting equipment to the project areas?