DEPARTMENT OF THE AIR FORCE

HEADQUARTERS 72 AIR BASE WING (AFMC)

TINKER AIR FORCE BASE OKLAHOMA

19 May 2026

MEMORANDUM FOR AFSC/PZIOC (ATTN: Tamra Torres)

THROUGH: 72 ABW/CENM

FROM: 72 ABW/CEED

Tepa Companies

SUBJECT: Pre-Bid RFI Responses Project: WWYK240176, Replace Industrial Waste Lift Stations 6N &6S, B62501

Reference: Memo, 12 May 2026, Pre-Bid RFIs, WWYK240176, Replace Industrial Lift Waste

Stations 6N & 6S, B62501

1. This office reviewed the referenced RFIs for the subject project and provided answers below. Please forward to the contractor(s) for their use in preparing proposals

(1) C-102 Keynote 5 & RFI #16. Please confirm how far West the new concrete driveway shall extend towards Warehouse Road.

Government Response: Keynote#5/Dwg #C-102 indicates new concrete pad within the gated area of the IWLS. No concrete pads, either driveway or sidewalks outside the IWLS area.

(2) Is the entire lift station yard to receive new gravel?

a. Is #57 stone acceptable gravel material for this application?

b. If required, please confirm the entire lift station yard shall be cleared/grubbed of existing vegetation

c. Is there a minimum thickness required for the new gravel?

Government Response: There is to be concrete drive into the area and a sidewalk to the lift station. The remaining space is to receive gravel.

a. #57 aggregates are acceptable to meet Oklahoma Department of Transportation

(ODOT) specifications for construction and drainage. The minimum aggregate size is ½” and maximum acceptable size is 1”. All crushed aggregate must be clean and washed without any fines.

b. All vegetation within the IWLS gated area to be removed and replaced with 6” lift of #57 aggregate.

c. 6” minimum thickness required.

(3) Will the Government require a geotextile fabric beneath the gravel? If so, is there a basis of design?

Government Response: Geotextile fabric will not be needed since this is not a drainage layer under roadway.

(4) The civil design narrative, para 3.3, states to provide drainage away from new lift station areas avoiding low spots and ponding. Please confirm the intent is to simply divert surface water away from the new lift station areas only & towards the culvert shown clouded below?

Government Response: Yes, the intent is to divert the surface water away from the new lift station areas and towards the culvert.

(5) There is an existing fire line that intersects the lift station yard / construction area.

Please confirm it is the design intent to reroute this line outside of the lift station yard.

Government Response: No, the design intent is to maintain the fire line in place and avoid relocation. As noted in the drawings the Contractor shall verify utilities and propose a space to minimize additional cost and/or delay to the Government.

(6) Please confirm the valves (shown below) exist per the “correct as-built” drawings from the RFI COR Response document dated 19 March 2026.

a. If the subject valves cannot be located, please confirm the contractor shall be required to install new valves to facilitate isolation of the North & South Lift stations

Government Response: This is the correct As-Built showing the feeder lines with associated gate valves. The contractor must exert all efforts to locate these valves. If these valves either cannot be located or found un-operable, the Contractor must coordinate with COR for concurrence and submit a request for replacement.

Please note that As-Built file 1994_IndWaste (June 1993) shows one 8” PP ‘Gravity Flow’ pipe with downstream flow into 6N branching into 6S. Before each LS, there is an 8” Gate Valve with associated Valve Box (for access). This As-Built supersedes As- Built file 1993_IndWaste (Line H from Bldg 2122) showing an 8” VCP Gravity pipe with downstream flow into 6S branching into 6N. The 8” VCP pipe has been abandoned and replaced by the 8” PP pipe. As-Built file 1993_IndWaste shows the 8” VCP ‘flushed and capped’ only and not removed. Please refer to sheet 9/11 details 2/C7- P.1 and sheet 10/11 details 10/C6-P.1.

As such, in your red-lined As-Built, above, there should be only 2 valves that are live, while the 3rd valve that is clouded, is part of an abandoned line: again the 8” VCP Gravity pipe.

(7) Please confirm the contractor shall provide a geotechnical report including boring logs to determine groundwater depths.

Government Response: As indicated in previous RFI response # 28, there was no evidence of high ground water levels in areas of close proximity. To reiterate this critical step, contractor is required to conduct their own investigation of sub-surface exploration not only to detect ground water levels (if any) but to obtain the soil bearing capacity needed for the proposed IWLS which we believe is mandatory for the design of the IWLS structure and foundation.

(8) Please confirm the design needs to be submitted to OCWUT for the fire line relocation.

Government Response: No, there is not an anticipated relocation of the fire line.

(9) If the design is required to be submitted to OCWUT please confirm they shall only review the fire line relocation scope of work.

Government Response: No, there is not an anticipated relocation of the fire line.

(10) Sheet P-501 Valve Vault indicates connection to two industrial waste lines in the Valve

Vault.

a. Is the intent to connect to both existing 6” INW lines in the valve vault?

b. If both are connected to the lift station, will they both be operational at the same time? Operating both lines changes the flow requires to provide the required minimum of 2 fps flow.

c. SOW Valve sections indicate transitioning from Ductile Iron to HDPE exterior to the valve vault. Material transition in the double wall system is less than desirable. Can HDPE piping be routed into the Valve box and flanged at the valve?

Government Response:

a. Yes, the intent is to connect to both existing 6” INW lines in the valve vault

b. No, both lines are not required to be operational at the same time.

c. Yes, HDPE piping can be routed into the Valve box and flanged at the valve.

(11) Sheet P-101 General Note 4 indicates (3) Submersible 100gpm pumps and Sheet

P101 Keyed Note 1 indicates peak Flow Rates for B2122 at 280gpm and 30gpm for B2136. Full operating of the (3) Submissible pumps would not provide the required 310gpm peak flow. To get the N+1 requirement in a (3) pump arrangement each pump would be sized for 50% of the peak flow, which would be 155 gpm minimum for each pump. Additionally, If the lift station force main discharge is limited to a single 6” line, the individual pump flow would need to be increased to 180gpm to maintain 2fps required by the same general note. For bidding purpose pump flows will be based on 180gpm at required head loss Government Response: Concur.

(12) It appears that some of the existing double wall piping is monitored. Is monitoring system operational? Are there as-builts for the monitoring system?

Government Response: The existing monitoring system is not operational and is not a part of the scope of work of this project.

(13) Which of the existing gravity and force mains piping system are double wall?

Government Response: Both force mains are double wall pipes and the gravity drains are single wall. Extend double wall piping of both force mains to the flow meter vault.

(14) Will monitoring wells be required at any of the double wall piping connections the new wet well or vaults?

Government Response: No, monitoring wells will not be required.

(15) Will the drain line between valve vault and wet well be required to be double wall?

Government Response: No, a drain line will not be required between the valve vault and wet well.

(16) Sheet P-101 Note 3: Can flow meter(s) be located in Valve Vault rather than constructing a separate vault for the flow meter(s).

Government Response: No, due to the required upstream straight length of pipe for the flow meters to operate properly.

(17) Will new isolation valves be required for the existing effluent line entering the wet well from B2122 and B2136?.

Government Response: Yes, new isolation valves will be required for the existing effluent line entering the wet well from B2122 and B2136

(18) The existing Gate tracks for gates to cross Douglas Blvd are located in the entrance to the lift station area. Are there any special closures or construction requirements for the gate and the tracks?

Government Response: No, there are not any special closures or construction requirements for the gate and tracks. Existing rail tracks outside the IWLS area must remain and be protected from damage. No proposed work outside the gated area.

(19) What government agency is responsible for the existing security cameras located on the telephone pole in the site? What are the requirements for outage of the security camera during construction to allow for installation of the new Lift Station?

Government Response: After further investigation, there is no agency coming forth and claiming ownership of this equipment. These cameras are no longer in use and have been abandoned in place. There will not be an outage required. This response supersedes previous Pre-Bid RFI #10 regarding the cameras.

(20) Please confirm what is inside the locked enclosure at the base of the camera pole? (Below picture).

Government Response: The enclosure shown inside the red circle is an exterior communication termination cabinet. This is grade-level cabinets serve as a critical transition point for fiber distribution or outside plan (OSP) splicing. In this specific application, this enclosure is installed in direct support of the wireless communication system for the existing lift station, ensuring reliable telemetry and control data transmission.

2. The points of contact for this project are:

a. Gloria Butcher, Project Manager. PH: 582-4830

b. Mark Williams, Construction Inspector. PH: 582-9042

c. Joshua Wheeler, CSAG Program Manager. PH: 582-4826

d. Randall Floyd, Contracting Officer Representative (COR). PH: 730-320-6068

Gloria Butcher Randall Floyd Project Manager 72 ABW Engineer/COR 72d Civil Engineering Directorate (Tepa) 72d Civil Engineering Directorate

0 Attachment(s):

cc:

Project folder