PORT OF SEATTLE 
MEMORANDUM 
COMMISSION AGENDA               Item No.       5d 
ACTION ITEM             Date of Meeting    May 28, 2013 

DATE:    May 20, 2013 
TO:      Tay Yoshitani, Chief Executive Officer 
FROM:   Mike Ehl, Director, Airport Operations 
Wayne Grotheer, Director, Aviation Project Management Group 
SUBJECT:  North Satellite (NSAT)Satellite Transit Station (STS) Ceiling Leak Long-Term
Repair (CIP #C800609) 
Amount of This Request:  $ 220,000     Source of Funds:  Airport Development Fund 
and future revenue bonds 
Est. State and Local Taxes: $ 105,000     Est. Jobs Created: TBD 
Est. Total Project Cost:    $1,750,000 
ACTION REQUESTED: 
Request Port Commission authorization for the Chief Executive Officer to design and prepare 
construction documents for the 2014 NSAT-STS Ceiling Leak Long-Term Repair Project in the
amount of $220,000. The total estimated project cost is $1.75 million.
SYNOPSIS: 
This project will eliminate ceiling leaks at the North Satellite (NSAT) that occur between the
satellite transit station (STS) and the elevators. Rainwater currently infiltrates through the
severely cracked topping slab. T he existing water-proofing membrane between the topping slab
and underlying structural slab is now over 40 years old and has exceeded its service life. There
is also inadequate drainage to keep water from ponding on the slab. The combination of the
cracked slab, inadequate drainage, and non-functional water-proofing membrane allows water to
enter the interior of the NSAT at the STS lobby. Ceiling leaks create risk in an area witha high
amount of passenger traffic that contains electrical and mechanical equipment, such as
escalators. The timing of the project is critical to limit exposure of the interior of the STS lobby
to weather while exterior components are being replaced. The design is to be completed by the
first quarter of 2014 to allow construction to occur during the driest months of 2014. Although
planned as an independent project, the construction phase could be included as part of the
NorthSTAR program, which will remodel the entire North Satellite, should the construction
schedules coincide. While it is unlikely this will be the case, staff wants to preserve the option to
combine with NorthSTAR if possible. If the project proceeds as a stand-alone project, Port staff
will return to the Commission in the first quarter of 2014 to request authorization for
advertisement for construction bids and for construction funding.

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
May 20, 2013 
Page 2 of 5 
This project was not included in the 2013  2017 capital budget and plan of finance because the
urgency of the project was not anticipated at the time the capital budget was prepared. The
budget will be transferred from the Aeronautical Allowance and the funding sources will include
the Airport Development Fund and an anticipated 2014 revenue bond issuance. 
BACKGROUND: 
The North Satellite was constructed in the early 1970s. As part of this project, a concrete
topping slab was installed over a structural "waffle slab" at Gate N10. The original design had
several design deficiencies. The existing topping slab is relatively thin, which has contributed to
its now being severely cracked. The thin characteristic of the topping slab is inadequate to
withstand the deflections from live loads applied to the underlying waffle slab. The original
design did not provide a needed relief interlayer between the topping slab and the waffle slab that
would help to prevent the topping slab from cracking. The drainage installed at the time was
inadequate and is no longer functional. The combination of the thin topping slab; no interlayer; 
and deflection of the underlying waffle slab by live loads that approach the design limits of the
structural slab, has resulted in significant cracking and failure of the topping slab. The asphalt
waterproofing membrane that was originally installed between the topping slab and waffle slab is
now more than 40 years old, and needs to be replaced. Currently, water ponds on the topping
slab, enters the interior of the North Satellite STS lobby through the cracked topping slab and the
failing water-proofing membrane, and drips from the ceiling onto the STS lobby floor and
equipment such as the escalators.
The Aviation Maintenance Department has made previous attempts to eliminate the surface
water from entering the terminal. Staff has removed the STS lobby ceiling panels and attempted
to seal cracks from below, which has had limited success. Maintenance has also sealed cracks in
the pavement slab at Gate N10, which helped reduce the amount of water entering the NSAT but
the results have only been temporary. The placement of plastic buckets and sheets, as well as
other measures within the NSAT, has been required to address the water entering the facility.
There currently is risk to airline passengers, staff, and the infrastructure of the terminal from the
water leaks. 
The existing elevation of the waffle slab, airfield panels, and NSAT is a constraint on installing a
thicker topping slab or interlayer that would help in preventing future cracking of a rigid topping
slab. Accordingly, rigid and flexible pavement alternatives will be evaluated during the design 
for resistance to cracking, structural integrity, ease of maintenance, service life, and cost.
Regardless of the pavement type selected, it is anticipated that future projects will need to
replace the components at a more frequent interval than 40 years. The replacement interval will
depend upon the weight and frequency of live loads applied to the waffle slab and the reasonably
expected service life for the materials used to replace the original installation. Airline
realignment is currently underway and it is anticipated that the heaviest tugs will not continue to 
use the area resulting in less live loads and deflections. This should help to increase the interval 
between future replacements.

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
May 20, 2013 
Page 3 of 5 
PROJECT JUSTIFICATION: 
The failing topping slab, inadequate drainage, and aging water-proofing membrane in the
vicinity of Gate N10 allows rainwater to enter into the interior of the North Satellite above the
STS station and escalators. The presence of water in the STS lobby could present risk to Airport
patrons, staff, and building infrastructure. 
Project Objectives: 
Eliminate rainwater from infiltrating into the STS lobby that could present a risk to
Airport patrons, staff, and infrastructure. 
PROJECT SCOPE OF WORK AND SCHEDULE: 
Scope of Work: 
Produce a final design for preventing rainwater from pooling on the ramp pavement and leaking
into the STS Lobby. The design will involve pavement replacement, drainage improvements, and
installing a new waterproofing membrane. 
Schedule: 
Commission Design Authorization                May 2013 
Begin Design                             June 2013 
Final Design                               December 2013 
Commission Authorization to Advertise and Construct    January 2014 
Advertise                                 January 2014 
Construction                               July to September 2014 
FINANCIAL IMPLICATIONS: 
Budget/Authorization Summary:           Capital      Expense   Total Project 
Original Budget                             $0         $0         $0 
Previous Authorizations                        $0         $0         $0 
Current request for authorization               $220,000         $0     $220,000 
Total Authorizations, including this request        $220,000         $0     $220,000 
Remaining budget to be authorized           $1,550,000        $0    $1,550,000 
Total Estimated Project Cost               $1,750,000         $0    $1,750,000 
Project Cost Breakdown:                 This Request     Total Project 
Construction                                  $0       $1,115,000 
Construction Management                      $0       $280,000 
Design                                $140,000       $140,000 
Project Management                       $80,000       $90,000 
Permitting                                   $0         $20,000 
State & Local Taxes (estimated)                     $0        $105,000 
Total                                    $220,000       $1,750,000

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
May 20, 2013 
Page 4 of 5 
Budget Status and Source of Funds: 
This project was not included in the 2013-2017 capital budget and plan of finance. The budget of
$1,750,000 was transferred from C800404, Aeronautical Allowance, to C800609 North Satellite
(NSAT)Satellite Transit Station (STS); thus there is no change to the 2013-2017 capital budget.
The funding source is the Airport Development Fund and future revenue bonds. The plan of
finance assumes there will be a revenue bond issue in 2014 to fund a number of projects. 
Financial Analysis and Summary: 
CIP Category             Renewal / Enhancement 
Project Type              Infrastructure Upgrade 
Risk adjusted discount rate     N/A 
Key risk factors             N/A 
Project cost for analysis        $1,750,000 
Business Unit (BU)          Aeronautical  Apron Area Cost Center 
Effect on business performance  NOI after depreciation will increase. 
IRR/NPV             N/A 
CPE Impact             $0.01 by 2015 but no change to business plan forecast
as this project was included. 
Lifecycle Cost and Saving: 
The lifecycle costs and savings will be established during design and will depend on the
resurfacing material selected for the topping slab. 
STRATEGIC OBJECTIVES: 
Maintaining critical airfield assets supports the Port's Century Agenda objective to meet the
region's air transportation needs at Sea-Tac for the next 25 years. 
ENVIRONMENTAL SUSTAINABILITY: 
During the design, various sustainable practices will be considered and implemented when
practicable. These include, but are not limited to, performing a life cycle cost analysis of
materials for replacement of the topping slab. 
BUSINESS PLAN OBJECTIVES: 
This project furthers the Airport's business plan objectives to operate a world-class international
airport by ensuring safe and secure operations and by managing our assets to minimize the total
long-term cost of ownership. 
ALTERNATIVES CONSIDERED AND THEIR IMPLICATIONS: 
Alternative 1) Do nothing: This alternative would result in rainwater continuing to enter the
interior of the STS lobby and require ongoing maintenance to try to limit the amount of water
that enters. The presence of water on the floor in a high pedestrian traffic area could cause risk
to Airport patrons and staff from slips and falls. Water leaking through the slab could potentially

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
May 20, 2013 
Page 5 of 5 
damage the interior and building infrastructure, such as the escalators.  This is not the
recommended alternative. 
Alternative 2) Replace the topping slab and improve drainage: This alternative will r emove and
replace the failed concrete topping ramp slab at Gate N10, repair cracks in the underlying
structural waffle slab, install adequate drainage, repair cracks in the waffle slab, replace the
water-proofing membrane on top of the waffle slab, replace the topping slab with either asphalt
or concrete pavement, and applying sealant. This alternative would best eliminate the potential
risk to Airport patrons, staff, the interior of the NSAT, and electrical infrastructure. This is the
recommended alternative. 
OTHER DOCUMENTS ASSOCIATED WITH THIS REQUEST: 
Project Vicinity Map 
Photos 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS: 
None