COMMISSION 
AGENDA MEMORANDUM                        Item No.          8l 
ACTION ITEM                            Date of Meeting     December 14, 2021 

DATE:     December 3, 2021 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Eileen Francisco, Interim Director, Aviation Facilities and Capital Programs 
Wayne Grotheer, Director, Aviation Project Management 
SUBJECT:  Industrial Wastewater Treatment Plant Program (CIP# C801234)  Preliminary
Design Funding 
Amount of this request:             $2,000,000 
Total estimated project cost:        $100,000,000 to $200,000,000 
ACTION REQUESTED 
Request Commission authorization for the Executive Director to (1) execute a contract for
Architecture and Engineering (A&E) services to complete planning and preliminary design for the 
Industrial Wastewater Treatment Plant (IWTP) Program (CIP C801234). The amount of this
request is $2,000,000. 
EXECUTIVE SUMMARY 
This project will install a pre-treatment system and upgrade the existing systems at the IWTP to
ensure compliance with future King County Department of Natural Resources Industrial Waste
Discharge permit limits. 
The airport's IWTP manages and treats stormwater associated with industrial activities from
aircraft fueling and maintenance operations as well as wastewater from other airport-related
operations such as aircraft deicing. Stormwater runoff with low Biochemical Oxygen Demand
(BOD) discharges to the Puget Sound  under conditions of National Pollutant Discharge
Elimination Systems (NPDES) permit. Stormwater runoff with high BOD discharges to King County
South Treatment Plant for secondary treatment under King County Department of Natural
Resources Permit No. 7810-05. The primary source of high BOD is aircraft deicer runoff. Effective
in 2026, the King County BOD permit limits will be restricted to a level that will require an on-site 
pre-treatment system at the SeattleTacoma International Airport (STIA). 
The amount of this request is $2,000,000 for planning efforts and preliminary design. The total
estimated project cost is currently $100,000,000 -  $200,000,000. Staff will return to the
Commission following the completion of the preliminary design work; at this time staff will

Template revised January 10, 2019.

COMMISSION AGENDA  Action Item No. __8l__                               Page 2 of 5 
Meeting Date: December 14, 2021 
provide an updated project cost estimate and request authorization for design funding to move
forward with the full design phase. 
JUSTIFICATION 
Since 2007, the IWTP has discharged industrial wastewater runoff containing aircraft deicers to
the King County Wastewater Treatment System. Through each permit cycle, King County has
restricted discharges because under sustained heavy deicer loads, the performance of the
County's treatment plant has been disrupted by the Port's discharges. 
Over the past five years, the Port has evaluated technologies and methods to reduce impacts to
the King County treatment plant. This evaluation included a comprehensive assessment of
deicing source control, storage, and treatment technologies. This assessment resulted in
measures to reduce the amount of aircraft deicer applied and implementing operation 
efficiencies. For example, most of the aircraft deicer applicators switched to an application
technology reducing the amount of deicer applied. This source reduction reduces the amount of
future storage needed. 
Under the terms of the July 2021 Industrial Waste Discharge (IWD) permit, the Port is required
to implement infrastructure and operational modifications by 2026 to comply with future
discharge limits. The IWTP modifications needed to comply with reduced limits include significant
additions to the system for storage and pretreatment of IWS stormwater containing spent
aircraft deicing fluid. The 2021 IWD permit also includes a compliance schedule over the next five
years to reflect progress toward implementation of measures to meet reduced 2026 effluent
limitations. 
The requested authorization will establish preferred pretreatment configuration, necessary
infrastructure improvements, and location that includes necessary IWTP upgrades, storage and
pretreatment. 
Diversity in Contracting 
As part of the planning phase of this project, a service directive will be issued against an existing
indefinite delivery / indefinite quantity (IDIQ) contract. An aspirational goal of 16% WMBE
participation is associated with this IDIQ contract. 
DETAILS 
Planning funds will be used to develop: 
Detailed Basis of Design (treatment configuration, storage options, infrastructure needs) 
Project Notebook 
Updated cost estimate 
Evaluation of siting and permitting requirements 
The preliminary design will develop scope for a pre-treatment system, water storage, and all
associated mechanical support systems. The pre-treatment system will need to be integrated

Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. __8l__                               Page 3 of 5 
Meeting Date: December 14, 2021 
into the existing IWTP. The current plan is to issue a service directive against an existing indefinite
delivery / indefinite quantity (IDIQ) contract to complete the preliminary design. If an existing
contract cannot be utilized, a project-specific contract will be executed for A&E services. 
Scope of Work 
Preliminary design of the following systems will be included in the scope of the Project Notebook: 
(1)   Existing IWTP upgrades (lagoon mixing, upgrades to dissolved air flotation systems, etc.) 
(2)   Pre-treatment flow diversion and influent system 
(3)   Storage systems to facilitate pre-treatment 
(4)   BOD treatment system (aerated gravel beds, oil-water separator, drainage, etc.) 
(5)   Effluent discharge systems 
(6)   Pumps and systems to support rainwater reuse 
(7)   Support systems (new building, power supply, controls, security systems, HVAC) 
Schedule 
The current project schedule shows an in-use date between Q4 2026 - Q2 2027. The dates shown
below are based on conservative assumptions in procurement, permitting, and construction.
Options to further compress the schedule will be evaluated during the planning phase to ensure
that discharge to the King County STP complies with anticipated 2026 BOD permit levels. 
Activity 
Preliminary design start                           2022 Quarter 1 
Commission design authorization               2022 Quarter 4 
Design start                                       2023 Quarter 3 
Commission construction authorization          2024 Quarter 4 
Construction start                                2025 Quarter 1 
In-use date*                                     2026 Quarter 4 - 
2027 Quarter 2 
* The planning phase will evaluate opportunities to compress the schedule. 
Cost Breakdown                                     This Request           Total Project 
Design                                                  $2,000,000                    TBD 
Construction                                                     $0                    TBD 
Total                                                         $2,000,000                      TBD 




Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. __8l__                               Page 4 of 5 
Meeting Date: December 14, 2021 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1  Do not proceed with this project. 
Cost Implications: Approximately $10,000 would need to be expensed. BOD levels would exceed
permit allowances and likely result in significant fines indefinitely. 
Pros: 
(1) No capital investment required at this time. 
Cons: 
(1) Failure to meet King County permit levels for the new permit cycle will leave limited
options for managing de-icing runoff at STIA. High BOD wastewater at the IWTP will not
be able to discharge to the King County South Treatment Plant. 
(2) In order to comply with reduced limits the IWTP current storage is not sufficient and could
result in overflow of untreated water into adjacent receiving waters. 
(3) High risk of violating King County and NPDES permit requirements. 
This is not the recommended alternative. 
Alternative 2  Conduct preliminary design to determine approach for implementation of a pre-
treatment system at the Industrial Wastewater Treatment Plant (IWTP). 
Cost Implications: $2,000,000 
Pros: 
(1)   Implementation of a pre-treatment facility on-site at STIA will allow continued discharge
to the King County South Treatment Plant. 
(2)   A preliminary design for the pre-treatment facility and associated systems will be
developed, allowing opportunities for review by stakeholders before full design
authorization. 
(3)   King County Department of Natural Resources requires a draft Engineering Report
describing the preferred on-site storage and treatment alternative by August 31, 2022.
This report must be sufficient to develop design documents and meet the requirements
of WAC 173-240-130. The preliminary design developed as part of this request will
satisfy the requirements of this report. 
(4)   The preliminary design will provide alternatives to reduce operational impacts and
project risks. Comprehensive existing conditions and permit requirements will be
evaluated, and an updated project cost estimate will be developed. 
Cons: 
(1)   Capital investment of $2,000,000 is required to develop preliminary design (current
total project estimate is $100M - $200M). 
This is the recommended alternative. 


Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. __8l__                               Page 5 of 5 
Meeting Date: December 14, 2021 
FINANCIAL IMPLICATIONS 
Following a third-party cost estimate, as part of the preliminary design, the project will update
the revised estimate for total project cost. 
Cost Estimate/Authorization Summary              Capital        Expense           Total 
COST ESTIMATE 
Original estimate                               $127,000,000               $0   $127,000,000 
AUTHORIZATION 
Previous authorizations                            $135,000               $0        $135,000 
Current request for authorization                $2,000,000               $0      $2,000,000 
Total authorizations, including this request       $2,135,000               $0      $2,135,000 
Remaining amount to be authorized                   TBD             $0            TBD 
Annual Budget Status and Source of Funds 
This project, CIP C801234, combined with C801123, is included in the 2022-2026 capital budget
and plan of finance with a budget of $127,000,000. While this appears to be a precise number,
there is significant uncertainty over the ultimate cost. The cost is estimated to be within a range
of $100 - $200 million. The funding sources would include the Airport Development Fund and
revenue bonds. The majority of the project costs would be recovered through airlines rates. The
Majority-In-Interest ballot would be submitted to the airlines for approval in late 2022. 
Financial Analysis and Summary 
Project cost for analysis              $127,000,000 
Business Unit (BU)                  Industrial Waste System 
Effect on business performance    NOI after depreciation will increase due to inclusion of
(NOI after depreciation)             capital (and operating) costs in airline rate base. 
IRR/NPV (if relevant)                N/A 
CPE Impact                       $0.32 in 2028 (ultimate CPE impact will vary with project
cost) 
Future Revenues and Expenses (Total cost of ownership) 
The addition of pre-treatment to the IWTP will require additional long-term resources for
operations, maintenance, and training. 
ATTACHMENTS TO THIS REQUEST 
(1)   Presentation 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
None 

Template revised June 27, 2019 (Diversity in Contracting).