580-26-103 Statement of Work Upgrade Cooling Tower.doc

Statement of Work 580-26-103 Upgrade Cooling Tower, Building 104

STATEMENT OF WORK

MICHAEL E. DEBAKEY VA MEDICAL CENTER

HOUSTON, TEXAS

Project Number: 580-26-103 Project Title: Upgrade Cooling Tower, Building 104

1. GENERAL:

Contractor shall provide services to include supervision, materials and labor for the rehabilitation of six 1,150 ton counter-flow induced draft cooling tower and two 1,250 ton. Rehabilitation shall include the replacement of fill material, the replacement of drift eliminators, the replacement of air inlet louvers and water distribution nozzles.

Contractor shall provide turnkey services, including all labor, materials, and necessary technical expertise to complete the renovation of all eight (8) counter‑flow induced draft cooling tower cells. A detailed list of required tasks is provided in the following sections.

Contractor shall provide all technical support and documentation needed during construction. These activities are part of the turnkey requirement and are not the responsibility of the Government, the Contracting Officer, or the COR.

Contractor shall engage qualified personnel to develop the required installation documents, coordination details, and final record drawings for structural, electrical, and BAS‑related work to ensure proper integration and performance of the renovated systems.

2. DESCRIPTION OF EXISTING EQUIPMENT

Cooling towers, rated at 1,150 tons, are situated on a basin with a coupling pipe providing a common sump. This sump can be isolated on a tower by tower basis for maintenance purposes. Each tower is equipped with a condenser water pump. The condenser piping manifold provides a common header for total versatility in connecting any specific chiller, CH-2 thru CH-7, with any specific tower, CT-2 thru CT-7.

The cooling towers, CT-2 thru CT-4, are equipped with condenser water bypass valves to accommodate the three potential winter use chillers. The cooling towers, CT-5 thru CT-7, are full flow towers to accommodate any chiller during the warmer months of the year and new replacement chillers in the future.

All chiller fans are equipped with variable speed drives (VSD) for modulating control at part load. Chiller plant operation is both manual and automatic. Chiller selection is manual and done by plant personnel as cooling demand dictates. The manifold concept provides greater flexibility in pairing chillers with towers, even in the cooler winter months. The condenser water temperature will be controlled by the JCI Metasys control system, modulating the bypass control valve where it exists and ramping the speed of the tower fans as water temperature increases.

Each chiller condenser is connected to its respective condenser return or supply header. Each tower is also connected to the condenser return or supply header. Cooling towers CT-2, 3, and 4 are equipped with a condenser water bypass valve. Existing chillers 2 thru 7 in the plant must have reasonably warm condenser water supply to operate properly. Load analysis indicates that throughout the winter months, November thru February, approximately three chillers are required to maintain load. Chillers 8 and 9, which are separate 1,250 ton machines located elsewhere, are used in this arrangement, providing 3,500 tons of capacity during peak usage. There have been peaks requiring 4,500 tons using the chillers 8 and 9.

Cooling Tower Schedule:

CT-2 thru CT-7

(1,150ton)

3. REQUIREMENTS

All work shall comply with the tower manufactures requirements and VA specifications.

4. WARRANTIES

One year warranty is required from the date of project completion once the government makes final acceptance.

5. PROPOSED SCHEDULE:

Contractor shall plan as necessary to ensure all parts and equipment are readily available before work is scheduled.

6. WORK LOCATION AND RESTRICTIONS:

The work site location is at the Michael E. DeBakey VA Medical Center in Houston, TX. The contract work is intended to be done at the cooling towers at building 104.

All work shall be done only on the weekdays, work on weekends and federal holidays shall be arranged in advance and approved in writing by the COR. When the contractor’s work interferes with hospital functions, such as when work produces excessive noise, odors, dust, utility service interruptions, or other interferences with normal hospital operations that cannot be contained within the area of work, the contractor shall schedule said work at other than normal hours and as directed by the VA COR.

7. PARKING:

Parking is rigidly controlled throughout the Medical Center. Contractor parking is only allowed in authorized areas. Contractor shall abide by all police requirements. Parking in designated patient parking areas is strictly prohibited. Parking for equipment necessary to perform the work will be authorized in advance of starting the project.

8. STORAGE OF EQUIPMENT & MATERIALS:

The contractor shall arrange with the VA COR for allocation of required workspace and for the storage of equipment and material to be used for this project. The Contractor should schedule delivery of materials to limit the amount of storage space and time.

9. DEBRIS REMOVAL

The Contractor/ shall be required to remove waste materials and debris daily from the campus. All waste material and debris shall be removed off the site by the contractor and shall be disposed of in accordance with applicable State and Federal regulations. All recyclable materials shall be recycled and weight tickets provided to the COR (i.e. piping, cooling tower steel, etc.).

10. SITE UTILITIES:

The Contractor should note this scope of work does not detail all existing structures, utilities, or components that may potentially interfere with the contract work required. The contractor shall note any obstruction, utility, or condition that may hinder or interfere with the execution of this contract during the pre-award site visit. All proposed utility relocations, reallocations, and shutdowns shall be approved by the COR prior to commencing such work. The contractor shall field verify all existing utility installations and take appropriate action prior to working around any potential utility installation.

In the event a shutdown, restriction, or interruption of any utility services is required, a written request must be submitted one week prior and approved by the VA COR. All utility shutdowns must be reviewed and approved by the COR.

11. PREVENTION OF FALSE FIRE ALARMS

Contractor shall comply with the requirements to prevent false fire alarms. Contractor shall provide a fire watch when impairment of the fire alarm system exceeds 4 hours in a 24 hour period.

12. TASK LIST

The following material replacement is included in the scope of work:

FOR TOWERS CT-2, -3, -4, -5, -6 and CT-7:

· Empty the basin one cooling tower at a time, isolate each cooling tower with a temporary dam, repairs cracks, apply coating and sealant.

· Provide and install temporary protection for sump drains / screens so debris cannot travel downstream to chillers

· Remove and dispose of existing counterflow Fill Media

· Remove and dispose of existing counterflow drift eliminators

· Remove and dispose of existing counterflow air inlet louvers

· Remove and dispose of existing side casing panels & internal partition walls

· Remove and dispose of existing Fan Assembly, Drive shaft, gear box, seal, motor, vibration cutoff switch

· Remove and dispose of existing water level controls

· Remove and dispose of existing internal water distribution system - header pipe, lateral piping & nozzles

· Provide and install new side casing panels & internal partition walls

· Provide and install new counterflow Fill Media, air inlet louvers, drift eliminators

· Provide and install new internal water distribution system – header pipe, lateral piping & high efficiency variable flow nozzles

· Provide and install (6) new aluminum fan assembly, drive shaft, bearing, pillow block, cooling tower rated motor, gear box & vibration cutoff switch.

· Remove temporary protection of sump drains / screens.

· Provide and install (6) new water level controllers

· Repair the electrical panels – refer to electrical drawing E5.0

· Install new fan motor (this is 60HP), contractor to verify compatibility of the existing motor size and upsize as required.

· Install new condenser pump and motor (this is 75hp), contractor to verify compatibility of the existing motor size and upsize as required.

· Install variable speed drives for the 60HP fan motor

· Install variable speed drive for the 75hp condenser pump. Contractor must provide technical support and engage qualified personnel to solve any compatibility issues for the installation of the motor control and variable speed drives.

· Install 12 new pipe support columns as per details in drawing M7, detail-6. Install new supply return condensing water pipe from the header. At no point the common header shall be allowed to by shut-off. There are no isolation valves, Contractor shall freeze and cut the pipes, install new isolation valves and tie-in the new piping. Contractor must provide technical support and engage qualified personnel to complete the installation pipe support columns and piping as a turnkey service.

· Correctly seal the gap around building exterior wall penetrations.

· The existing underground supply/return piping shall be abandoned in-place.

· Fill cold water basin with water and check work for proper operation.

· Inspect the casing and stair tower, water blast and paint the fiberglass structural casing.

· Clean & inspect jobsite upon completion

FOR TOWERS 104-CT-8, 104-CT-9:

· Empty the basin one cooling tower at a time, isolate each cooling tower with a temporary dam, repairs cracks, apply coating and sealant.

· Provide and install temporary protection for sump drains / screens so debris cannot travel downstream to chillers

· Remove and dispose of existing counterflow Fill Media

· Remove and dispose of existing counterflow drift eliminators

· Remove and dispose of existing counterflow slat louvers

· Remove and dispose of existing Fan Assembly, Drive shaft, gear box, motor, vibration cutoff switch

· Remove and dispose of existing water level controls

· Provide and install new counterflow Fill Media, slat louvers, drift eliminators

· Repair the existing water distribution system for both Cells

· Reinforce internal entrance walkway & Drift Eliminator support system for safe access to the interior of both cells

· Provide and install (2) new aluminum fan assembly, drive shaft, cooling tower rated motor, gear box & vibration cutoff switch

· Provide and install (2) new water level controllers

· Provide and install clear coat UV protection to all exterior casing panels

· Remove temporary protection of sump drains / screens

· Fill cold water basin with water and check work for proper operation Isolation of towers by others

For all eight cooling tower provide the following: water temperature sensor and monitor for the supply/return water piping. Water flow meter for each cooling tower condenser pump. The flow meter and temperature readings must be tied to the building automation so that heat exchange can be monitored in the BAS.

Fill: Fill material shall be PVC, resistant to rot, decay and biological attack, have a maximum flame spread rating of five per ASTM E84-81a and fabricated, formed and crossfluted bonded together for strength and durability in block format for easy removal and replacement, suitable for use as a working surface, able to withstand continuous operating temperature of 130F, and allowing the water to break up into droplets and shall be from OEM, alternate manufacturer must be approved by the VA.

Drift Eliminators: Same as fill material. Effectively trap water droplets entrained in discharge air stream and limit drift loss to less than 0.001 percent of the total water circulated. Sections shall be assembled into easily removable racks of the same material as the casing. Eliminators shall be PVC neoprene honeycomb type and shall be OEM, alternate manufacturer must be approved by the VA.

Air Inlet Louvers: Louver material shall be PVC, resistant to rot decay and biological attack, have a maximum flame spread rating of five per ASTM E84-81a and fabricated to provide optimization of air channels to maintain fluid dynamics and thermodynamic efficiency and blocks all line of site paths into the basin eliminating slash out. Air Inlet Louvers shall be , alternate manufacturer must be approved by the VA.

Water distribution nozzles: The water distribution nozzles shall be EvapJet ABS plastic water diffusers or equal. The wide orifice nozzles shall be mounted on the side of the existing pipe used in the AT water distribution system. The spray pressure for the AT Cooling Towers shall be between 1 and 6 psig (7 and 41 kPa) at the inlet header. The actual spray pressure shall be as required for the original unit or as recommended by the unit manufacture.

Condenser Water Pumps Scope of work:

Provide rigging, labor, and material for the replacement of SIX (6) condenser water pumps & EIGHT (8) Bray Control Valves & (8) Bray Bypass Control Valves Gauges and BAS:

Provide temperature sensors and monitoring devices on all supply and return piping, and provide a flow meter for each condenser pump. Monitoring points for both flow and temperature shall be installed above the piping and integrated with the BAS. The contractor shall coordinate with the BAS team to ensure software and hardware compatibility.

Controls for the condenser pumps and fan motors must be interconnected so the system operates as intended. The contractor shall engage qualified technical personnel to develop the necessary control integration details, documentation, and compatibility information to support proper installation and operation.

13. NEW CONDENSER WATER PUMPS:

The following description is an example, the vendor shall submit actual spec sheets and pump performance curves for VA approval. Note that COR will submit all documents to the VA HEFP for approval, the submittal approval process can take up to four weeks. Note that the replacement pump/motor shall not decrease the current heat and mass transfer capacity.

American-Marsh Pumps for VA Hospital Project: (6) Pumps for GEA towers, Flow, rated : 3,500.0 USgpm Differential head / pressure, rated (requested) : 65.00 ft Differential head / pressure, rated (actual) : 65.31 ft Suction pressure, rated / max : 0.00 / 0.00 psi.g NPSH available, rated : Ample Site Supply Frequency : 60 Hz Speed criteria : Synchronous Speed, rated : 1750 rpm Impeller diameter, rated : 10.94 in Impeller diameter, maximum : 11.75 in Impeller diameter, minimum : 10.78 in Efficiency (bowl / pump) : 81.78 / 77.39 % Liquid type : Water HP: 75 TEFC MOTOR ENCLOSURE

Sixteen (16) New Bray Valves & Actuators: Series 70 Valve , Eight (8) Bray cooling tower control valves, Eight (8) Bray cooling tower bypass control valves SIX (6) Condenser Water Pump EIGHT (8) CT Bray Bypass control valve & EIGHT (8) CT Bray control valve

14. EQUIPMENT LIST

Contractor must submit spec sheets for the following equipment after award, including, but not limited to:

· Tower Motors

· Gear Boxes

· Fan Assemblies

· Drive Shaft

· Water Level Controllers

· Vibration Cutoff Switch

· All Fill Media

· Condenser pump

· Fan Motor

· Sump screen

· Basin coating/sealant

· Water distribution system

· Casing panels

15. OPERATING AND TESTING

A.

Provide the services of a factory-authorized and qualified representative to perform start up service.

B.

Clean entire unit including basin.

C.

Inspect field-assembled components and equipment installation, including piping and electrical connections.

D.

Verify that accessories are properly installed.

E.

Obtain and review performance curves and tables.

F.

Perform startup checks, according to manufacturer's written instructions, and as noted below:

1.

Check clearances for airflow and tower servicing.

2.

Check for vibration isolation and structural support.

3.

Verify fan rotation for correct direction and for vibration or binding and correct problems.

4.

Adjust belts to proper alignment and tension.

5.

Lubricate rotating parts and bearings.

6.

Verify proper oil level in gear-drive housing. Fill with oil to proper level.

7.

Operate variable-speed fans through entire operating range and check for harmonic vibration imbalance. Set motor controller to skip speeds resulting in abnormal vibration.

8.

Check vibration switch setting. Verify operation.

9.

Verify operation of basin heater and control.

10.

Operate equipment controls and safeties.

11.

Recommend corrective action.

G.

Adjust water level for operating level and balance condenser water flow to each tower inlet.

H.

Check water treatment water system, including blow down for proper operation of the tower. Check makeup water-level control and valve.

I.

Start cooling tower, including condenser water pumps and verify the tower operation.

J.

Prepare and submit a written report of startup and inspection service to the Resident Engineer.

K Replace defective and malfunctioning units.

16. WORKMANSHIP QUALITY:

All workmanship shall comply with the manufactures recommendation and CTI standards. All work shall be done in a first class manner according to the best trade practices and to the satisfaction of the Project Manager.

The Contractor shall provide VA personnel with the necessary training to maintain all provided equipment and material prior to project closeout.

17. SECURITY:

All contractor personnel shall obtain a short-term identification badge issued by theVA. Such badge shall be worn by the individual and prominently displayed at all times while on VA property. No employee of the contractor shall enter the project site without a valid identification badge issued by the VA. In order to obtain a short-term identification badge, contractor personnel shall present to the COR two valid (non-expired) photo identification issued by a US federal, state or local government agency.

All contractor personnel are subject to inspection of personal effects when entering or leaving the project site.

18. SUBMITTALS

After contract award, the Contractor shall submit to the MEDVAMC the following:

Quality Control Plan. Contractor shall establish a quality control plan for all work, including that of his subcontractors, to assure compliance with the contract provisions. Contractor shall submit a copy of his quality control plan concurrently with the quote and schematic submission. Quality control measures shall include, but not be limited to:

· Obtaining payment and performance bonds, permits, licenses and insurance.

· Performing all required inspections and tests.

· Listing all subcontractors and services they will perform.

· Submittal approval.

· Inspection schedule.

· Compliance with applicable Federal, state and local codes and regulations related to executing the contract.

· Correction of unsatisfactory work.

Prior to construction the contractor shall submit all plans including, but not limited to:

· Environmental Protection Plan

· Waste Management Plan

The VA shall check government furnished and/or the DB construction contractor's shop drawings, detail drawings, schedules, descriptive literature and samples, testing labor- laboratory reports, field test data and review the color, texture and suitability of materials for conformity with the RFP Documents and construction documents. All submittals shall be in electronic format and include a VACT Submittal Cover sheet for return as annotated.

19. CODE REQUIREMENTS

The VA will be responsible for obtaining necessary local agency approvals as required.

All work performed under this contract shall be in accordance with the VA Master Specifications (http://www.cfm.va.gov/til/spec.asp). Particular attention needs to be given to the following sections:

01 00 00 General Requirements

23 65 00 Cooling Towers

26 05 11 Requirements for Electrical Installations

23 21 13 Hydronic Piping

All work shall comply with all local, state, and federal rules and regulations. In the event of a code discrepancy the stricter of the ordinances shall prevail.

20. WARRANTIES

Workmanship - One year warranty is required from the date of project acceptance by the VA.

All equipment motors, pump, gear box – five years warranty

All parts including fill material, switches, - three years warranty

21. PROPOSED SCHEDULE:

Mobilization will only occur after all plans, submittals, and equipment are approved by the government.

Construction sequencing will allow only one cooling tower to be taken offline until all work has been completed on that unit. Only when this unit is again fully functional and online and accepted by the VA COR can the next tower be taken offline for rehabilitation. Rehabilitation of each cooling tower shall last a maximum of three weeks per unit.

Contractor shall plan as necessary to ensure all parts and equipment are readily available to maintain this schedule.

When no longer needed, the temporary materials shall be removed and any disturbances to the grounds shall be restored to their prior condition.

22. WORK LOCATION AND RESTRICTIONS:

The work site location is at the Michael E. DeBakey VA Medical Center in Houston, TX. The contract work is intended to be done at the cooling towers at building 104.

All work shall be done between the hours of 7:00 am and 4:30 pm Monday through Friday, holidays excepted, unless other times are arranged in advance and approved in writing by the Project Manager. When the contractor’s work interferes with hospital functions, such as when work produces excessive noise, odors, dust, utility service interruptions, or other interferences with normal hospital operations that cannot be contained within the area of work, the contractor shall schedule said work at other than normal hours and as directed by the VA COR.

23. PROJECT SAFETY:

Contractor shall comply with the following and keep a copy of the attached on site at all times:

· OSHA

· Interim Life Safety Measure Assessment (completed on site by phase)

· Infection Control Risk Assessment (Not required at this time)

· Hot work Permits required as needed

· Confined Space Permits required as needed

24. PENETRATIONS OF FIRE AND SMOKE BARRIERS:

Prior to any installation of equipment, cables, power connections, conduit, piping or other work that penetrates a smoke or fire barrier, all such work must be approved by Facilities Management Service (FMS) of the VAMC. A penetration permit must be secured from FMS prior to disturbing the integrity of the barrier. The permit must be available for inspection at the project location. After the work is completed, the penetration must be repaired (sealed) according to accepted practice and utilizing materials (including UL/FM-listed through penetration fire stopping materials) that meet the original barrier construction requirements in order to restore the designed specifications for smoke and fire compartmentalization. All penetrations and miscellaneous openings must be protected according to NFPA 101, Chapter 8. Upon completion of any penetration repair, a visual inspection for approval must be requested from, and completed by FMS.