Works to investigate the soil there will involve a jack up platform. Here's more blog posts about the marine life seen in the area.
Soil investigation works off Tanah Merah
from Port Marine Notice No. 154 OF 2009 dated 2 Nov 09
With effect from 6 Nov 09 to 17 Dec 09, 24 hours daily including Sundays and Public Holiday. At Tanah Merah and its vicinity (see attached chartlet):
Soil investigation works will be carried out at BH1, BH2 and BH 3 one at a time by the jack up platform HJT No 1. The jack up platform with tug boat in attendance will have a circular safety working zone of 30 meters radius centered at the jack up platform. A tugboat will be used for shifting the jack up platform from one borehole location to another. Safety boat will be deployed in the vicinity of the working area to warn other craft of the project work. Further enquires relating to the project can be directed to Mr John Chai, the project manager at Tel: 8223 2929 (email: firstname.lastname@example.org).