McKay_Bay_WTE_Lightning_Protection_Evaluation_Report.pdf

July 15, 2025

LIGHTNING PROTECTION/GROUNDING

SYSTEM EVALUATION

MCKAY BAY WASTE-TO-ENERGY FACILITY

Evaluation Report

Prepared By:

Page i

TABLE OF CONTENTS

1 Executive Summary

Newly Installed Structures Pg. 1 Existing Facilities Pg. 1 Existing Stack Pg. 1

2 Purpose

Purpose Pg. 3

Scope

3.01 Lightning Protection/Grounding System Evaluation Pg. 4

3.02 Evaluation Report Pg. 4

Existing Conditions and Recommendations

Newly Installed Structures Pg. 5

4.01 Ash Building Pg. 5

4.02 Cooling Tower and Piping Pg. 10

4.03 Turbine Island Pg. 14

4.04 Warehouse Building Pg. 20

Existing Structures Pg. 24

4.05 Existing Administration Building and Tipping Building Pg. 24

4.06 Existing Stack Pg. 28

General Installation Recommendations Pg. 29

Appendix

5.01 Attachment “A” (Not Used)

5.02 Attachment “B” (Not Used)

5.03 Attachment “C” - Drawings for Stack Lightning

Protection. Pg. 45

Page ii

THIS PAGE INTENTIONALLY LEFT BLANK

1.0 EXECUTIVE SUMMARY

The need for lightning protection and grounding systems for buildings and structures at the McKay Bay Waste-To-Energy facility was evaluated. The findings of this evaluation are included in this report. This section provides an overview of the evaluation.

Newly Installed Structures

Recently constructed structures will require the installation of lightning protection and grounding to safeguard these structures from lightning damage.

Newly installed structures, including the Ash Building, the Cooling Tower and Piping, the Turbine Island, and the Warehouse Building were not equipped with lightning protection at the time of construction.

Each of these structures will require the installation of air terminals, ground conductors and a grounding system to protect them from lightning strikes. Each of these four (4) facilities will require the development of design drawings that will detail the placement of air terminals, show the routing of ground conductors and down conductors, and configure the grounding system layout. The design will follow the requirements set forth in NFPA 720, UL 96A and the National Electrical Code.

Existing Facilities

The Administration Building and Tipping Building will require replacement of the remains of the existing lightning protection system.

The existing Administration Building and Tipping Building both were equipped with lightning protection. However, aging and deterioration and the impact of last year’s hurricanes (Helene and Milton) have compromised the integrity of the installed lightning protection system. Therefore, it is necessary to replace what remains of the air terminals, bonding connections, ground conductors and down conductors for these two (2) buildings.

Existing Stack

Immediate installation of lightning protection air terminals on the existing stack is necessary to minimize damage and redirect lightning strikes to ground.

The existing stack is suffering repeated lightning strikes; therefore, an immediate solution is necessary for this structure.

Drawings and specifications were prepared by Engineering Design Technologies Corp. (EDT) to allow the City of Tampa to secure a contractor to equip the stack with supplemental lightning protection to stave off the repeated lighting strikes presently experienced.

2.0 PURPOSE

The purpose of this report is to:

1) Review the lightning protection and associated grounding system for the Administration building and the Tipping Building.

2) Evaluate the Ash Building, Cooling Tower and Piping, Turbine Island, and

Warehouse Building to determine the need for equipping these recently-installed structures with air terminals, bonding conductors, down conductors and ground system for proper lightning protection in accordance with UL 96A and NFPA 780.

3) Determine what is required to equip the existing Stack with appropriate lightning protection. Evaluate the existing installations to determine the adequacy of these installations and the need to fortify these existing installations with air terminals, down conductors and grounding.

3.0 SCOPE

3.01 Lightning Protection/Grounding System Evaluation

1) Evaluate the newly installed structures, Ash Building, Cooling Tower and Piping, Turbine Island, and Warehouse Building, for equipping these structures with lightning protection and grounding of the lightning protection system. This evaluation will include the need for air terminals, bonding conductors and ground system for the lightning protection system.

2) Evaluate the existing facilities, Administrative Building and Tipping Building, for the adequacy of the installed lightning protection and grounding system.

Field evaluations will include the adequacy of the air terminals, bonding conductors, down conductors and grounding system for proper lightning protection in accordance with UL 96A and NFPA 780.

3) Determine what is required to equip the existing Stack with appropriate lightning protection, including air terminal(s), down conductors and grounding. Examine the existing installations to determine the adequacy of such for interim and/or permanent service. This will be given the highest priority for immediate remediation.

3.02 Evaluation Report

An Evaluation Report will be prepared to document the findings of the Lightning Protection/Grounding System needs at the McKay Bay WTE Facility. This report will document the existing conditions and provide recommendations for new installations, replacements and modifications to provide reliable and long-term service. Budgetary cost estimates will also be provided for each recommendation.

No design services, design drawings or specifications are included in the Scope.

4.0 EXISTING CONDITIONS AND RECOMMENDATIONS

NEWLY INSTALLED STRUCTURES

The Ash Building, Cooling Tower and Piping, Turbine Island and the Warehouse Building were constructed in 2024. These buildings and structures did not include lightning protection in the design or construction.

4.01 Ash Building

Existing Conditions

The Ash Building is a pre-engineered steel frame structure with steel panel siding and a steel panel roof that is approximately 19,152 square feet (171’ x 112’). This building has three (3) roof top units (RTU’s) that extend approximately 4’ above the roof surface. Each of these RTU’s will need to be equipped with air terminals as part of the overall lightning protection system for the building.

Photograph 4.01-1 - Ash Building.

Photograph 4.01-2 - Grounding conductor bonded to stairway.

Photograph 4.01-3 - Damaged and unconnected length of grounding conductor extending below grade.

Photograph 4.01-4 - Grounding conductors routed above grade.

Photograph 4.01-5 - Waste Water Tank should be bonded to Ash Building grounding system.

Photograph 4.01-6 - Roof surface and RTU’s on the Ash Building, requiring lightning protection.

Photograph 4.01-7 - Ash Conveyor Gallery will require air terminals to be installed.

Recommendations

Approximately thirty-five (35) air terminals will be required to provide lightning protection for the Ash Building and the Ash Conveyor Gallery.

These air terminals will be required to be positioned on the top of the RTU’s and along the center of the roof, as well as, on 20’ centers around the perimeter of the building. The handrail for the access stairway to the roof of the Ash Building should also be protected with an air terminal.

The Ash Conveyor Gallery should have four (4) air terminals affixed to the top of the conveyor roof, along its centerline.

Copper ground conductors shall bond together all the air terminals. The air terminals and the ground conductors shall be affixed to the surface of the roof using securing bases and adhesive.

Approximately six (6) down conductors will be needed to connect the roof-mounted air terminals to the grounding system around the perimeter of the building.

The Waste Water Tank, adjacent to the Ash Building, will be protected from lightning strikes by the air terminals mounted on top of the Ash Building.

Therefore, no additional lightning protection will be necessary for the Waste Water Tank. Grounding conductors for the Ash Building should be extended to and bonded to the Waste Water Tank to ensure an equipotential condition is maintained between the Ash Building and the Waste Water Tank.

Grounding conductors are presently routed on top of the surfaces around the building perimeter and are bonded to the building steel, stairway steel, equipment enclosures and steel structures and supports. The condition of the below grounding system and ground rods is unknown. Drawings of the Ash Building from 1999 show the presence of a grounding conductor and ground rods around the building perimeter. Measurements of the existing grounding system to ground resistance should be made to verify the integrity of the existing grounding system. This resistance should be 5 ohms or less.

Resistance of more than 5 ohms will require supplementary ground rods to be driven and bonded to the existing grounding conductors until 5 ohms resistance or less is achieved.

The existing grounding conductors routed on the surfaces around the outside of the Ash Building should be replaced with conductors routed below grade or the grounding conductors should be routed in conduits.

These existing grounding conductors, routed on the surface around the Ash Building, are subject to damage from work activities or maintenance operations. Additionally, existing cable clamps should be checked for tightness and to ensure low resistance connections.

The proper integrity and bonding of the building steel and steel building panels to the grounding system should be tested. Improper connections or broken connections should be reconnected.

4.02 Cooling Tower and Piping

The Cooling Tower structure is mounted on a reinforced concrete base and is about 60’ in height. The top of the Cooling Tower has an area of approximately 3,300 square feet (60’ x 55’). The top deck of the Cooling Tower has two (2) cooling fans that are each approximately 25’ in diameter.

The shroud around each fan is non-metallic and extends 8’ above the deck.

The perimeter of the Cooling Tower deck has pole-mounted lighting fixtures secured to the railing.

The Cooling Tower Piping and the associated structural supports extend between the Cooling Tower and the Turbine Island.

Photograph 4.02-1 - Cooling Tower.

Photograph 4.02-3 - Cooling Tower Piping.

Photograph 4.02-2 - Non-metallic shrouds for Cooling Tower fans.

Ten (10) air terminals should be affixed to the top of the pole-mounted lighting fixtures and railing around the perimeter of the Cooling Tower top deck, at 20’ centers. The lighting fixtures on the top deck extend above the Cooling Tower fan shrouds; therefore, the air terminals mounted on the lighting fixtures will afford lightning protection for the cooling fans.

Four (4) down conductors will be necessary to bond the air terminals atop the Cooling Tower to a grounding system at the base of the Cooling Tower.

There is no evidence of a grounding system at the base of the Cooling Tower. The installation of a grounding system will be required at the base of the Cooling Tower to ground the Cooling Tower lightning protection system. The stairway and the steel structure of the Cooling Tower should be bonded to this grounding system.

Approximately ten (10) air terminals and two (2) down conductors will be necessary to provide lightning protection for the Cooling Tower Piping.

Air terminals and ground conductors will be affixed to the structural members supporting the Cooling Tower Piping, using securing bases and adhesive. In the area near the Cooling Tower where the piping extends above the structural supports, air terminals will be secured to the piping.

Ground rods will be driven along the routing path of the Cooling Tower Piping. This additional grounding should be grounded to the grounding system for the Cooling Tower and the Turbine Island.

Photograph 4.02-4 - Cooling Tower Piping.

Photograph 4.02-5 - Top deck of the Cooling Tower. Air terminals will be mounted on the lighting fixtures around the perimeter.

4.03 Turbine Island

The Turbine Island includes the roof above the old electrical room and the new electrical room, the fiberglass enclosure for the turbine, an elevated deck with the process piping and vessels for the turbine steam feed and condensate treatment. The Turbine Island is approximately 4,340 square feet (140’ x 31’), including the upper deck with the steam process vessels and piping.

Photograph 4.03-1 - Turbine Island.

Photograph 4.03-2 - Fiberglass Turbine Enclosure on Turbine Island. Steam Process Vessels and Piping are Located on the North End of the Turbine Island.

Photograph 4.03-3 - Pole-Mounted Lighting Fixtures and Railing Around the Deck Will Provide Mounting Locations for Air Terminals.

Photograph 4.03-4 - Fiberglass Turbine Enclosure will have Air Terminals Mounted on Top of Enclosure.

Photograph 4.03-5 - The Height of the Piping Will Require Air Terminals to be Mounted on Pole-Mounted Lighting Fixtures and 9’ Stanchions.

Photograph 4.03-6 - Existing Grounding System Bonded to Steel Column.

Photograph 4.03-7 - Existing Grounding System Bonded to Steel Column.

Lightning protection for the Turbine Island will require the installation of nineteen (19) air terminals. Air terminals should be secured to the existing pole-mounted lighting fixtures, positioned around the perimeter of the Turbine Island. The additional elevation of the air terminals placed on the pole-mounted lighting fixtures will afford more reliable protection from lightning. In addition to the air terminals being mounted on the pole-mounted lighting fixtures, air terminals should be affixed to the top of the railing around the perimeter of the Turbine Island. These air terminals around the perimeter of the Turbine Island, mounted on the railing and the pole-mounted lighting fixtures, should be placed at 20’ intervals.

The upper deck with the steam process vessels and piping will need to be equipped with two (2) stanchions, extending approximately 9’ above the deck, for mounting air terminals. These stanchion-mounted air terminals will be placed on the north and south ends of the elevated deck.

Three (3) additional air terminals should be placed along the axis of the top of the fiberglass turbine enclosure. These air terminals and ground conductors should be mounted using securing bases and adhesive.

Six (6) down conductors will be required for connecting the air terminals on the Turbine Island to the grounding system at grade level below the Turbine Island.

Photograph 4.03-8 - Steel Column Bonded to Grounding System.

The existing electrical substation, near the Turbine Island, and the electrical equipment in the old electrical room and the new electrical room have a solid grounding system. Additional grounding rods and grounding conductors should be bonded to the existing grounding system to accommodate the grounding needs of the new air terminal installations.

The overall grounding system should be tested to ensure a resistance of 5 ohms or less exists between the grounding system and ground.

The integrity of the existing grounding connections to the building steel should be verified and steel structures not bonded to the grounding system should be bonded and grounded.

4.04 Warehouse Building

The Warehouse Building is a pre-engineered steel frame structure with steel panel siding and a steel panel roof that is approximately 3,900 square feet (130’ x 30’). The roof is peaked with five (5) vents placed on top of the roof peak.

Photograph 4.04-1 - Warehouse Building.

Photograph 4.04-2 - Peaked Roof of Warehouse Building with Vents.

Photograph 4.04-3 - Ground Rod with Bare Copper Conductors.

Lightning protection for the Warehouse Building will require seven (7) air terminals mounted along the peak of the roof.

Air terminals will be affixed directly to the vents and the roof surface with securing bases and adhesive. All the air terminals will be connected together with copper ground conductors. Securing bases and adhesive will also be used to secure the ground conductors to the roof surface.

Four (4) down conductors will be required to connect the roof-mounted air terminals to a grounding system around the perimeter of the building.

There are ground rods with bare copper conductors extending above ground at four (4) locations around the perimeter of the Warehouse Building.

These conductors are presumed to be grounding conductors that are connected to a grounding system. Field conditions gave no insight as to the extent or make-up of a grounding system. Before connecting the air terminals to these “grounding conductors”, the resistance to earth should be measured. If the resistance from the “grounding conductors” to earth exceeds 5 ohms, additional grounding rods should be driven and connected to the grounding system until a resistance of 5 ohms or less is achieved.

The grounding system should be bonded to the building steel in a minimum of four (4) locations.

Photograph 4.04-4 - Ground Rod with Bare Copper Conductors.

EXISTING STRUCTURES

4.05 Existing Administration Building and Tipping Building

The Administration Building and Tipping Building had been equipped with lightning protection. Over the years, the air terminals and ground conductors have suffered the ill-effects of the corrosive environment and heat. Last year’s Hurricanes Helene and Milton further damaged the lightning protection system, rendering it ineffective. With the state of the existing air terminals and ground conductors, as well as, the securing hardware, it is not economically feasible to repair the existing lightning protection system.

The existing air terminals, ground conductors, fastening hardware and down conductors should be removed and replaced with a new lightning protection system. There is no reason to believe the existing grounding system needs to be replaced. There is no visual evidence that construction or excavation damaged the below-grade grounding conductors, ground rods or connections.

The roof of the Administration Building is approximately 12,222 square feet (63’ x 194’). The Tipping Building is approximately 21,120 square feet (96’ x 220’).

Photograph 4.05-1 - Roof of Tipping Building.

Photograph 4.05-2 - Air terminals and ground conductor on roof of Administration Building.

Photograph 4.05-3 - Roof of Administration Building.

No air terminals or ground conductors remain.

Photograph 4.05-4 - Damaged down conductor on side of Tipping Building.

Photograph 4.05-5 - Air terminals and ground conductors on top of Tipping Building.

A new lightning protection system shall be installed on the roof of the Administration Building and the Tipping Building. Air terminals shall be placed at approximately 20’ intervals around the perimeter of each roof and at 20’ intervals along the centerline of each roof. This will require approximately 130 stainless steel air terminals. Air terminals should be fastened to the roof surfaces and any structures extending above the roof structures with adhesive.

Copper ground conductors shall interconnect the air terminals and be secured to the roof surfaces with bronze fastening pads and adhesive. The ground conductors should be bonded to approximately nine (9) down conductors bonded to the grounding system. These down conductors should be installed at strategic locations around the perimeter of the Administration Building and the Tipping Building.

The resistance of the existing grounding system to earth should be measured before connecting the lightning protection system to the grounding system. The resistance of the grounding system to ground should be 5 ohms or less. If the resistance to ground exceeds 5 ohms, additional ground rods should be driven and bonded to the existing grounding system until a resistance of less than 5 ohms is achieved.

4.06 Existing Stack

The existing stack, with four (4) 48” diameter steel liners, is not equipped with air terminals to aide in protection against lighting strikes. The design drawings from 1999 did not include air terminals; however, the four (4) steel liners and all conductive materials are bonded to ground conductors. These ground conductors were in turn attached to two (2) down conductors that are bonded to an underground ground ring and ground rods at the base of the stack.

The principal of lightning protection included in the design drawings was to allow the steel liners serve as the air terminals. The steel liners, as well as, the ground conductors allows the current from lightning strikes to be shunted to ground.

To address the immediate concern for inadequate lightning protection, Engineering Design Technologies Corp. (EDT) provided drawings and specifications on December 10, 2024 to allow remediation of the lightning protection issue. The drawings and specifications will allow a Contractor to install enhancements to the existing grounding system to mitigate lightning strike damage.

Fortification to the existing ground system for the stack includes the installation of eight (8) air terminals and supplemental ground conductors.

Drawings and specifications provided are included in Attachment “C” of this report.

General Installation Recommendations

Design drawings and specifications should be developed to detail the equipment and installation requirements for the lightning protection and grounding system for the building and structures at the McKay Bay Waste-To-Energy Facility. This will ensure the installations comply with NFPA 780 and UL 96A. Additionally, competitive bid pricing can be secured to award the work at the most economical price.

An overview of design features should be incorporated in the lightning protection/ grounding installations at the McKay Bay Waste-To-Energy Facility to include:

1. Air terminals shall be stainless steel in lieu of aluminum.

2. Air terminals shall be Class II in lieu of Class I.

3. Conductors shall be Class II copper, not aluminum.

4. Air terminal base material shall be bronze, not aluminum.

5. Cable holders shall be copper, not aluminum.

6. Bonding lugs shall be bronze, not aluminum.

7. Cable connectors shall be copper, not aluminum.

8. Bonding plates shall be bronze, not aluminum.

9. Thru-roof penetrations shall not be allowed.

10. The grounding system shall have a resistance to earth of not more than 5 ohms. The resistance to earth shall be field measured and recorded for each ground system prior to connecting the lightning protection system.

5.0 APPENDIX

5.01 Attachment “A” (Not Used).

5.02 Attachment “B” (Not Used).

5.03 Attachment “C” - Drawings For Stack Lightning Protection.

5.03 ATTACHMENT “C”

Drawings For Stack Lightning Protection

PROJECT NO.:

DRAWN:

DESIGNED:

DATE:

QC:

SCALE:

Technologies Corp.

engineering@edt1.com

813.289.8080

Tampa, FL 33684-2403

P.O. Box 152403

Engineering Design

PROJECT TASK

NO. DATE BY DESCRIPTION

REVISIONS

FLORIDA REGISTRATION NO. 20761

BOB E. HALLMAN, P.E.

ENGINEER OF RECORD:

LIGHTNING PROTECTION

McKAY BAY WTE FACILITY

EVALUATION

LIGHTNING PROTECTION

SMOKE STACK

STACK - PLAN VIEW

STACK - ELEVATION

- PRELIMINARY - FOR REVIEW

ONLY NOT FOR CONSTRUCTION

PROJECT NO.:

DRAWN:

DESIGNED:

DATE:

QC:

SCALE:

Technologies Corp.

engineering@edt1.com

813.289.8080

Tampa, FL 33684-2403

P.O. Box 152403

Engineering Design

PROJECT TASK

NO. DATE BY DESCRIPTION

REVISIONS

FLORIDA REGISTRATION NO. 20761

BOB E. HALLMAN, P.E.

ENGINEER OF RECORD:

LIGHTNING PROTECTION

McKAY BAY WTE FACILITY

EVALUATION

PROTECTION DETAILS

SMOKE STACK LIGHTNING

AIR TERMINAL MOUNTING DETAILS

- PRELIMINARY - FOR REVIEW

ONLY NOT FOR CONSTRUCTION