Amendment 02--RFP LBNF-372669-JD.pdf

AMENDMENT TO SOLICITATION

AMENDMENT NO.

DATE OF AMENDMENT:

December 31, 2025

SOLICITATION NO.

RFP LBNF-372669-JD

DATE ISSUED:

November 05, 2025

PROJECT NO.

N/A

PROPOSAL DUE DATE:

January 23, 2026

TITLE OF PROJECT:

LONG-BASELINE NEUTRINO FACILITY LAR CIRCULATION

Offerors must acknowledge this Addendum prior to the hour and date set forth in the solicitation by one of the following methods:

1. By completing the Subcontractor Annual Representations and Certifications (SARC), or

2. By separate fax, letter, or email.

If by virtue of this Addendum you desire to change a proposal already submitted, such change may be made by email, provided such email clearly references the Solicitation number and this Amendment number and is received prior to the proposal due date.

Amendment No. 2 is issued to extend the offer closing date, answer vendor questions, and provide a new technical file for reference purposes as follows:

(1) THE OFFER CLOSING DATE IS HEREBY CHANGED TO January 23, 2026 AT 5:00 P.M.

CENTRAL STANDARD TIME (CST-CHICAGO).

(2) As stated in Amendment 1, FFDG Answer #2, a 3D model of the assemblies (valve boxes, equipment protection, vent header) is provided with Amendment 2.

(3) Answers to final technical questions submitted by prospective offerors are provided as follows:

Vendor Question 1: Please provide the required LAr circulation flow rate(s), pressure differential, and operating conditions for both VD and HD systems. These parameters directly determine line sizing and component selection.

Answer No. 1: Each individual valve box will house a circulation pump. The internal piping / control valves shall be able to withstand the larger of the two pressure/flow conditions between the fill and normal mode of operations which would in this case be the fill:

• Liquid Argon Temperature assumed: 87 K

• Gas Argon Temperature assumed: 310 K

• Flow rate: 20 kg/s

• Inlet Pressure at suction side of pump: 1.21 bara

• Discharge Pressure at discharge side of pump: 5.91 bara

• Pressure differential across the pump will be 4.3 bar

Pressure drops across the valve will need to sized with correct Cv’s to not restrict pressure/flow required to discharge to an interface point.

This interface pointed is identified in the Figure below as Point 2:

Question No. 2: Please provide maximum allowable pressure drop limits between each defined tie-point in the updated P&ID. Without these limits, piping and component sizing cannot be established.

Answer No. 2:

See Figure above.

• V1 is a hand valve:

o

• V2 is a control valve:

o

• F1 is a flowmeter o o

• Overall Pressure Drop from valves + instrumentation:

o

• Piping Pressure drop is assumed with use of 4” Pipe. Note that the discharge piping outside of the valve box that is factored into this equation is not in the scope of this acquisition.

Vendor Question No. 3: Please confirm the required material grade (304L, 316L, AL-6XN, etc.) for LAr and GAr piping, vacuum-jacketed lines, and valve box internals. Material selection has a major impact on cost.

Answer No. 3: All piping must be 304/304LSS.

Vendor Question No. 4: Please clarify the insulation requirements for the circulation piping, including:

whether vacuum-jacketed piping is required, required vacuum level, MLI layer count (if applicable), and jacket material and thickness.

Answer No. 4: MLI insulated piping will be required inside the valve box. The thickness of the piping shall be determined by vendor using ASME B31.3 as the guideline.

The number of layers is determined by vendor’s calculation for maintaining heat leak of 1 W/m^2.

Valves shall be purchased as vacuum jacketed, bellows sealed valves w/ actuators, positioners and limit switches.

Vendor Question No. 5: Please define which aspects of the valve box geometry are fixed and which must be designed by the vendor (e.g., internal manifolding, supports, insulation, vacuum envelope, structural reinforcement).

Answer No. 5: See attached.

Vendor Question No. 6: Please provide available 3D spatial information or constraints for routing between tie-points (elevations, offsets, clearances, transport limits). This is needed to estimate pipe lengths and number of spools.

Answer No. 6: See attached.

Vendor Question No. 7: Please provide performance and selection requirements for pressure transmitters, temperature elements, flow meters, and valve actuators shown symbolically on the P&ID. A specification sheet for each class of instrument would be sufficient.

Answer No. 7: Knowing the process parameters the vendor shall be able to properly spec out the instrumentation. Note that they must have 4-20 mA signal. Note that the flowmeter must be outside the valve box for any required maintenance or replacement meaning it must be vacuum jacketed. The RTD’s must be spring loaded.

Vendor Question No. 8: Please clarify the required PSV sizing basis (heat ingress, vacuum loss, overpressure scenarios, etc.), or confirm the vendor is responsible for full relief calculations.

Answer No. 8: Vendor will need to properly size the relief valves per CGA S1.3. The vacuum valves must be sized for loss of insulating vacuum case. The piping relief valves must be sized for overpressurization (1.1x);

fire case does not need to be considered. As a reminder that since the valve box is not ASME coded, then it will not need to be an ASME rated relief valve.

Vendor Question No. 9: Please confirm whether cold testing must be performed at the vendor facility, at FNAL, or after installation underground. This affects both cost and facility preparation.

Answer No. 9: Cold testing will need to occur at vendor’s facility. Subsequent leak checking and pressure testing will also need to occur at vendor’s facility.

Vendor Question No. 10: Please provide warm and cold leak-rate acceptance thresholds for piping, valve boxes, and vacuum jackets.

Answer No. 10: 1x10-9 mbar-l/sec.

Vendor Question No. 11: Please confirm whether oxygen cleaning is required for all LAr-wetted surfaces and specify the applicable standard.

Answer No. 11: Vendor to supply a cleaning procedure for ultra high purity standards for Fermi review and approval. This does not just apply to LAr wetted surfaces, vacuum side of the valve box shall also fall into same criteria to eliminate outgassing.

Vendor Question No. 12: Please confirm whether 50%, 90%, and 100% engineering drawing reviews are required for approval prior to fabrication start.

Answer No. 12: A 50% and 100% review would suffice.

Vendor Question No. 13: Please define the expected FAT scope (pressure test, leak test, instrumentation checks, valve cycling, etc.).

Answer No. 13: There is a table in the SOW that clearly identifies the testing required with NP and HP.

Vendor Question No. 14: Please identify any maximum module dimensions or weights for underground transport and installation.

Answer No. 14: Attached is the latest shaft dimensions which constrain the size.

Vendor Question No. 15: Amendment 1 notes that FFDG intends to release a 3D model of assemblies in a future amendment. Please confirm whether this model will be provided before proposal submission, or should vendors assume geometric uncertainty when estimating fabrication effort.

Answer No. 15: See attached file provided with Amendment 2. Model is only for reference.

Vendor Question No. 16: Given that piping lengths, routing, valve box internals, and insulation requirements have not yet been defined, please confirm whether fabrication pricing may be submitted as a budgetary estimate pending completion of detailed engineering.

Answer No. 16: Firm prices are needed to evaluate bids. Any exceptions should be clearly stated in your proposal.

Vendor Question No. 17: Can you confirm whether the 3D model will be issued during the RFP period, and whether it will include accurate piping routing, elevations, and spatial constraints, or if it is reference-only?

Answer No. 17: No this model is for reference only.

Vendor Question No. 18: Are you planning to route the Pressure Safety Valves to common headers and remotely discharge?

Answer No. 18: PSV discharge to a common vent header (also part of this scope).

Vendor Question No. 19: The drawing includes strict nozzle load limits and required straight lengths upstream/downstream. Can FNAL provide details for mounting plate thickness, allowable loads, and attachment method so vendor-side piping/support loads can be calculated?

Answer No. 19: Pump vendor has identified 10 diameters of straight length before and after the pump. The pump drawing was attached as part of this bid for reference of weight and size of mounting plate that vendor needs to supply to account for it.

Vendor Question No. 20: Is there a site layout that has the routing requirements for the system? For which side lines leave valve boxes, etc.

Answer No. 20: See reference model provided with Amendment 2.

Vendor Question No. 21: Does FNAL require or prefer specific vendors for valves, sensors, cryogenic components, or vacuum hardware?

Answer No. 21: No, please advise on vendors that subcontractor plans to use. Important thing is to have material traceability.

Vendor Question No. 22: Can FNAL provide a draft FAT/PRR checklist or acceptance criteria to support accurate timelines?

Answer No. 22: It is in the SOW.

All other provisions remain unchanged.

Fermi Forward Discovery Group, LLC P.O. Box 500 Batavia, IL 60510 M.S 123

Jeremy Duncan LBNF Procurement Specialist

(865) 300-0443