COMMISSION AGENDA MEMORANDUM BRIEFING ITEM Item No. Date of Meeting 11a September 22, 2026 DATE: August 12, 2026 TO: Stephen P. Metruck, Executive Director FROM: Stephanie Jones Stebbins, Managing Director Maritime Sarah Ogier, Director, Maritime Environment & Sustainability Jon Sloan, Sr.Manager, Environmental Programs Mike DeSota, Sr. Env. Program Manager, Maritime Environment & Sustainability SUBJECT: Green Marine International Environmental Certification Program EXECUTIVE SUMMARY Green Marine International is a voluntary environmental certification program developed specifically for the maritime industry. The program provides ports, ship owners, terminals, shipyards, and other maritime organizations with a structured and transparent framework for measuring environmental performance, implementing best practices, and demonstrating continual improvement beyond regulatory compliance. The Port of Seattle has participated in Green Marine since 2013 and was the first U.S. West Coast port to achieve Green Marine certification. Through annual evaluations and periodic independent verification, the program provides an objective framework to benchmark environmental performance and identify opportunities for continued improvement. This briefing will provide the Commission with an overview of the Green Marine program, the Port's participation and performance over time, and opportunities for continued environmental improvement. No Commission authorization or funding action is requested. GREEN MARINE PROGRAM AND PORT PARTICIPATION Green Marine provides a transparent framework for measuring maritime environmental performance beyond regulatory compliance. The Port has consistently demonstrated strong performance across applicable environmental performance indicators addressing greenhouse gas and air emissions, spill prevention, stormwater management, aquatic ecosystems, waste management, community relations, environmental leadership, and underwater noise. Port Environmental Performance The Port's Green Marine performance is one of the highest scores among all ports participating in the program and it reflects the Port's continued investment in shore power and maritime electrification, habitat restoration, stormwater management, spill prevention, community engagement, and efforts to better understand and reduce underwater noise. Green Marine participation supports the Port's broader environmental and sustainability objectives and aligns Template revised April 12, 2018. COMMISSION AGENDA - Briefing Item No. 11a Meeting Date: September 22, 2026 Page 2 of 3 with the Century Agenda goal of positioning the Port of Seattle as one of the greenest and most energy-efficient ports in North America. Tables 1 and 2 illustrate the Port's Green Marine Performance from 2013 to 2025. Achieving Level 5 - the program's highest rating requires participants to demonstrate environmental excellence and leadership through rigorous, measurable criteria that go beyond regulatory compliance. Table 1. Port of Seattle - Green Marine Performance (2025) Table 2. Port of Seattle- Green Marine Performance (2013-2025) Template revised September 22, 2016. COMMISSION AGENDA - Briefing Item No. 11a Meeting Date: September 22, 2026 Page 3 of 3 ADDITIONAL BACKGROUND Eleanor Kirtley, Ph.D., of Green Marine International will provide an overview of the program, with Port staff available to discuss the Port's performance, programs, and ongoing environmental initiatives. Results are publicly reported annually and independently verified every two years, providing Commissioners, customers, community members, and other stakeholders with an external measure of the Port's environmental performance. ATTACHMENTS TO THIS BRIEFING (1) Presentation slides Template revised September 22, 2016.