The yellow dots on that map mark locations at the office/marina complex on the south end of Harbor Island [map] where soil sampling is about to start as Sound Transit continues studying potential routes for West Seattle light rail. The full flyer is here (PDF). It says that once sampling starts – as soon as tomorrow – “Work … will occur during nights, from 6:00 pm – 7:00 am. Each boring will take approximately 5-7 days and will be filled and patched with a flush-mounted monument surface when work is complete.” The drilling will all be done in parking lots/driveways, ST says.
SIDE NOTE: If you have questions about this or any other aspect of West Seattle light-rail planning, a reminder – ST reps are on the agenda at tonight’s Junction Neighborhood Organization meeting. And two upcoming ST board meetings will determine whether two West Seattle options are included in environmental studies – the System Expansion Committee this Thursday, and the full board on October 24th.