COMMISSION 
AGENDA MEMORANDUM                        Item No.          8a 
ACTION ITEM                            Date of Meeting        July 9, 2019 
DATE:     June 18, 2019 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Jeffrey Brown, Director Aviation Facilities and Capital Programs 
Wayne Grotheer, Director, Aviation Project Management 
SUBJECT:  Electric Utility Switching Project (CIP #C800699) 
Amount of this request:              $10,350,000 
Total estimated project cost:         $11,950,000 
ACTION REQUESTED 
Request Commission authorization for the Executive Director to: (1) increase the authorized
funds for the Electric Utility Supervisory Control and Data Acquisition (SCADA) project in the
amount of $10,350,000; (2) advertise and award a major works construction contract at
Seattle-Tacoma International Airport; and (3) use Port crews and small works contracts to assist
with the project. The total estimated cost of this project is $11,950,000. 
EXECUTIVE SUMMARY 
This project will install an industrial computer system to allow for the safe operation,
monitoring, and control of the electrical power distribution system at Sea-Tac Airport. This
SCADA system will be installed throughout Sea-Tac Airport providing a complete, fault-tolerant
control and data acquisition system. The SCADA system will serve 26 medium-voltage supply
power distribution centers (12,470V 480V) and two utility substations (12,470V) and will
enable compliance with current electrical safety regulations. 
The original project budget set before the start of project design was $9,650,000, with an
authorized work project budget of $1,600,000. The new budget estimate is $11,950,000, an
increase of $2,300,000. This budget increase includes additional scope: a new Electrical
Command & Control Center room and Bow Lake substation upgrades required by Puget Sound
Energy. In addition to scope additions, the project budget was determined to be insufficient to
cover the construction and soft costs associated with the original scope of work.
Funding for this project was included in the 2019-2023 capital budget and plan of finance. The
capital budget increase will be transferred from the Aeronautical Allowance #C800753 resulting
in no net change to the Aviation Division capital budget. 

Template revised January 10, 2019.

COMMISSION AGENDA  Action Item No. _8a__                               Page 2 of 7 
Meeting Date: July 9, 2019 
JUSTIFICATION 
The Seattle-Tacoma International Airport's 12,470V power distribution system is a complex
network of transmission lines, substations, load centers, power centers, and switchgear that
supply electricity to all parts of the Airport. 
SCADA  systems  perform  four  functions,  (1)  Data  acquisition,  (2)  Networked  data
communication, (3) Data presentation, and (4) Control.  The SCADA system provides a safe,
reliable, and efficient method to operate, monitor, and control switchgear remotely.  SCADA
systems are crucial for at critical facilities such as airports and hospitals, since they help to
maintain efficiency, process data for smarter decisions, and communicate system issues to help
mitigate downtime. 
Project objectives include the following: 
Personnel safety 
Minimize system downtime and associated operational disruption to the airlines and
tenants, including significant reduction in time to recover from full loss of electrical
power, by switching all power loads to the recently completed Alternate Utility
Facility (AUF). The AUF provides 30 megawatts of standby power to Sea-Tac airport,
more than enough power to fully support the airport's electrical requirements. 
Optimally balance electrical loads across the entire power distribution network 
Record event and meter data for historical reporting and analysis 
Quickly identify and pinpoint problems or potential problems within the system 
Develop and add a new Electrical Command and Control Center (EC3) Room 
This project is necessary to meet requirements within national electrical and safety codes that
are enforced by the Washington Department Labor & Industries. The benefits of this project
include meeting code, ensuring worker safety, minimizing breadth and duration of future
power outages, and extending lifespan of electrical circuits and breakers. SCADA systems are
used by industrial organizations and companies in public and private sectors to control and
maintain efficiency, distribute data for smarter decision making, and communicate system
issues to help mitigate downtime. 
Using a SCADA system will provide the means and methodology for qualified personnel to
operate switchgear remotely, without unsafe human exposure to the arc flash hazard. In 2014,
new electrical safety regulations were enacted regarding arc flash hazards. Arc flash occurs
when electrical power does not follow its intended path. The resulting explosion can cause
serious injury, or death. The new regulations require quantification of the inherent dangers of
arc flash events. To meet this requirement, the Port completed an arc flash hazard study and
labeled all distribution equipment with the known arc flash hazard data. Roughly 50 percent of
all 12,470V - 480V power distribution centers were determined to have arc flash incident

Template revised September 22, 2016; format updates October 19, 2016.

COMMISSION AGENDA  Action Item No. _8a__                               Page 3 of 7 
Meeting Date: July 9, 2019 
energy in excess of 40 cal/cm2. Personnel are prohibited from local operation of switchgear
with arc flash energy above 40 cal/cm2. 
In addition to the benefits of safe switchgear operation, the SCADA system will provide a means
to monitor and respond to power distribution failures and outage events as they occur in real
time. Sea-Tac Airport currently does not have a system that identifies power distribution
events; electricians need to work back through the system to try to identify the source of a 
power interruption. The SCADA system will identify the source and root cause of current and
potential future power interruptions in real time. This knowledge will expedite return to normal
operations after an interruption. 
In the current environment, if switchgear requires operations and/or maintenance activities, all
power on that feeder circuit must be shut off, at the main breaker. The power interruption will
lead to major disruptions in power service and associated lengthy interruptions to airline and
airport  operations.  Additionally,  under  current  conditions  it  is  not  possible  to  perform
preventive maintenance of the power distribution centers. The SCADA system will monitor and
quickly identify and pinpoint problems, or potential problems within the approximately 140
12,470V switchgear breakers located throughout the Airport. The monitoring of vital
performance indicators will target which switchgear pieces need preventive maintenance and
provide the least  amount of disruption to the Airport while maximizing the lifecycle of
switchgear and breakers. 
The project scope has been increased to include a new Electrical Command and Control Center
that will serve as the centralized location for the SCADA system. This remote monitoring and
control of the 26 major equipment locations will allow for faster response time to power
outages and will provide safety to our Electricians by removing them from the room that
houses the equipment. 
Another major benefit this SCADA system provides is the ability to efficiently and swiftly
connect the north portion of the airport to the recently completed Alternate Utility Facility
(AUF) which provides back-up power to the airport; this includes North Satellite and Concourse
D. Without SCADA, airport electricians estimated it will take their group in excess of 8 hours to
fully transfer the airport to AUF generator power. SCADA will provide the ability to transfer all
airport load to the AUF within a few minutes. 
Diversity in Contracting 
Project staff is working with the Diversity in Contracting Department to outreach and set the
woman and minority business enterprise (WMBE) aspirational goal.
DETAILS 
Key features and benefits of the SCADA system: 
Permits the safe operation of the electrical power distribution system at Sea Tac Airport 

Template revised September 22, 2016; format updates October 19, 2016.

COMMISSION AGENDA  Action Item No. _8a__                               Page 4 of 7 
Meeting Date: July 9, 2019 
Allows quicker response to power distribution failures and outage events 
Allows remote monitoring and control at medium voltage power switchgear 
Metering upgrades to provide real time voltage, current, power and frequency
information 
Enables the efficient use of the Alternate Utility Facility (AUF) 
Efficient and rapid transfer of Airport load to the AUF facility during a power outage
scenario. 
Ability to "island" (disconnect) the airport from the primary utility (Puget Sound
Energy) and power the airport from the AUF facility. 
Provides new Electrical Command and Control Center (EC3) 
Addresses arc flash concerns within the Airport's Medium Voltage System, as required
per National Electrical Code (NEC) by providing for remote operation 
Scope of Work 
Since project conception and pre-design budget development the following new scope has
been added to the project. (new unfunded project scope $1,550,000) 
(1) The design and construction on an Electrical Command and Control Center (EC3).  The
EC3 will provide a single point of information collection, analysis, and power system
dispatch for the Sea-Tac airport campus. The costs associated with this new scope are
estimated at $650,000 
(2) During design review with the local power utility it was determined that substantial
work on the Bow Lake Substation (owned and operated by Puget Sound energy), which
provides high voltage power to Sea-Tac airport, was required. Work includes indication
of Port of Seattle breaker positions at PSE dispatch, reverse power relaying to prevent
back feeding into the utility grid, and other construction activities necessary for the
successful implementation of SCADA integration with the AUF facility.  This work is
estimated at $900,000.
Since pre-design budget development the original project scope was determined to be
underfunded by $750,000.
The original project scope included: 
Installing, integrating, configuring and testing a SCADA system for the Airport's 12,470V power
distribution network. The SCADA system will monitor and control switchgear breakers at the
Airport's North and South Main Substations, the North and South Terminal Load Centers, the
South Terminal Expansion Project distribution center and switches at twenty-two 12,470V-480V
power centers. 
The SCADA system included an interactive Graphical User Interface that provides operators a
dynamic display of the Airport's power distribution network and enables remote switching

Template revised September 22, 2016; format updates October 19, 2016.

COMMISSION AGENDA  Action Item No. _8a__                               Page 5 of 7 
Meeting Date: July 9, 2019 
operations. The system will record event and meter data for historical reporting and analysis. A
new Electrical Command and Control Center will be built as a central point for system
operation. Upgrades to metering will provide real time voltage, current, power and frequency
information. 
The SCADA system will be built on Programmable Logic Controllers installed at each of the
substations, distribution centers, and power centers with digital input/output wired to each
12,470V breaker to provide remote breaker status and switching capability. Furthermore,
operational information will be monitored and recorded for each of the switchgear breakers
controlled. 
Schedule 

Design complete                                   1st Quarter 2020 
Construction start                                    2nd Quarter 2020 
In-use date                                           2nd Quarter 2022 
Cost Breakdown                                      This Request           Total Project 
Design                                                       $633,000             $2,233,000 
Construction                                             $9,717,000             $9,667,000 
Total                                                        $10,350,000             $11,900,000 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1 Do not implement a SCADA system 
Cost Implications: $1,575,000 spent to date would need to be expensed 
Pros: 
(1)   No Capital Expenditure 
Cons: 
(1) This does not meet code safety requirements for workers 
(2) Electrical distribution maintenance or power outage recovery will require widespread 
electrical interruptions in power service including lengthy interruption to airport and
airline operations 
(3) Labor intensive medium voltage (12.5kV) switching operations
(4) No remote monitoring or control capability 
(5) Lack of data acquisition 
(6) Not integrated with Alternate Utility Facility (AUF) 
(7) 8-hour minimum transfer time to AUF generator power without SCADA 
(8) Does not address arc flash concerns within the Airport's Medium Voltage System, as
required per National Electrical Code (NEC) 

Template revised September 22, 2016; format updates October 19, 2016.

COMMISSION AGENDA  Action Item No. _8a__                               Page 6 of 7 
Meeting Date: July 9, 2019 
(9) No metering upgrades providing real time voltage, current, power and frequency
information 
This is not the recommended alternative. 
Alternative 2  Install a fully integrated SCADA system at individual substations, power centers,
and distribution centers. 
Cost Implications: Capital Cost $11,950,000 
Pros: 
(1)   Permit the safe operation of electrical power distribution systems at Sea Tac Airport 
(2)   Minimize system downtime and associated operational disruption to the airlines and 
tenants through more efficient operation of the electric utility system 
(a) Allow quicker response to power distribution failures and outage events 
(b) Optimally balance electrical loads across the entire power distribution network 
(c) Remote Monitoring and Control at Medium Voltage Power Switchgear 
(3)   Enable the efficient use of the AUF 
(a) Ability to island the airport from Primary Utility 
(b) Ability to transfer to AUF generator power within minutes 
(4)   New Electrical Command and Control Center (EC3) room 
(5)   Upgrades to metering will provide real time voltage, current, power and frequency
information. 
(a) Records event and meter data for historical reporting and analysis 
Cons: 
(1)   Outages may be required to install system 
(2)   System will require resources and training to fully utilize capability 
This is the recommended alternative. 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary               Capital        Expense           Total 
COST ESTIMATE 
Original estimate                                 $9,600,000         $50,000      $9,650,000 
Current change                                 $2,300,000              $0      $2,300,000 
Revised estimate                               $11,900,000         $50,000     $11,950,000 
AUTHORIZATION 
Previous authorizations                          $1,600,000               $0      $1,600,000 
Current request for authorization               $10,300,000         $50,000     $10,350,000 
Total authorizations, including this request      $11,900,000         $50,000     $11,950,000 
Remaining amount to be authorized                    $0             $0             $0 


Template revised September 22, 2016; format updates October 19, 2016.

COMMISSION AGENDA  Action Item No. _8a__                               Page 7 of 7 
Meeting Date: July 9, 2019 
Annual Budget Status and Source of Funds 
The Electric Utility Safety Switching Project #C800699 was included in the 2019-2023 capital
budget and plan of finance. The budget increase of $2.3 million will be transferred from the
Aeronautical Allowance #C800753 resulting in no net change to the Aviation Division capital
budget. The funding sources will include the Airport Development Fund and revenue bonds. 
In 2015, this project of $9.6M was approved by the airline through a Majority in Interest (MII) 
vote. The budget increase necessitates another vote. The project was presented to the Airport
Airlines Affairs Committee (AAAC) on June 27, 2019 without any objections to project moving
forward. 
Financial Analysis and Summary 
Project cost for analysis              $11,950,000 
Business Unit (BU)                  Electrical Utility (allocate to Terminal Building) 
Effect on business performance     NOI after depreciation will increase 
(NOI after depreciation) 
IRR/NPV (if relevant)                N/A 
CPE Impact                        $0.03 in 2022 
Future Revenues and Expenses (Total cost of ownership) 
The life expectancy of the SCADA system is 40 years, with the programmable logic controllers
and headend equipment needing upgrades every 10 years. The SCADA system not only
enhances personnel safety, but also quickly identifies and pinpoints problems or emerging
potential problems within the system; thus, saving time and valuable maintenance resources. 
ATTACHMENTS TO THIS REQUEST 
(1)   Presentation slides 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
August 4, 2015  The Commission authorized $1.56 million for a design contract and
preparation of design and construction bid documents for the Electric Utility Switching
Project at Seattle-Tacoma International Airport. The commission also authorized use of
port crews for the project. The total project estimate at that time was $1.6 million. 




Template revised September 22, 2016; format updates October 19, 2016.