Tar ponds will get boring

Engineers need to drill into bedrock beneath north and south ponds

By Tanya Collier Macdonald
Cape Breton Post
Wed. Jan. 10, 2007

SYDNEY - Bedrock under the tar ponds will get numerous pokes over the next eight weeks as engineers try to get a firmer grasp on what lies underground.

"They burrow a small hole, it's probably about two and a half inches in diametre," said Wilf Kaiser, acting director of environmental services for the Sydney Tar Ponds Agency. Air emissions aren't expected, "but in keeping with our approach, we'll definitely be doing real-time air monitoring specific to this activity."

Kaiser said although there are likely small fractures, there is little risk that contamination will be released from the ponds.

Maritime Testing Ltd., a Dartmouth firm, and Boart Longyear Inc., a Moncton company employing a local driller, will use a barge-mounted drill rig to collect 39 core samples from both the north and south tar ponds. Earth Tech and CBCL will oversee the job.

Although samples were previously taken from the ponds, that work focused on sludge settled on the bottom of the tar ponds, not the bedrock.

This time, crews will drill 1.6 metres deep and extract samples in areas along the same route that's been selected to channel water from Coke Ovens Brook and Wash Brook. The channel will provide a clean path for water travelling through the tar ponds and into Sydney harbour.

Project manager Joe Sullivan said the samples will provide crucial information needed when the walls of the channel are anchored to the bedrock. Results will influence the final design of the sheet pile wall.

The channel design will use the western shoreline of the tar ponds to form one side of the channel and the eastern side will be built using interlocking steel sheet pile.

The barge is expected to arrive at the site Friday and drilling will likely begin Monday.