DFO to clean up oily contamination at busy Nova Scotia harbour
Groundwater contamination underneath pavement at Kraut Point wharf in Riverport
No one knows the source of the oil or gas that has seeped into the ground at Kraut Point in Riverport on Nova Scotia's South Shore.
Also, no one knows how much is in the plume riding on top of ground water below the pavement at the busy commercial fishing harbour outside Bridgewater.
But one thing is clear — cleaning it up is going to be expensive.
The federal government has already spent $758,000 studying the site and will spend another $1.6 million over the next five years to clean it up.
"This project is very extensive, it is one of the most complex projects that we're working on," says Roxanne MacLean, a senior environmental officer with Fisheries and Oceans Canada.
Pollution not spreading
Testing over the past decade has shown the pollution has contaminated about 1,000 square metres.
It is not spreading, an indication it's been there for a while, and it hasn't escaped into the ocean nearby.
"There is no sheen going into the water," said MacLean. "It has not entered the water body, and we want to make sure that it never does."
How they will clean it up
This month, an extraction unit will be constructed on site.
Ten wells have already been installed. They will be used to pump and vacuum what is known as light non-aqueous-phase liquid, or LNAPL, at an expected rate of two litres per minute, night and day, for two years.
The site will be monitored for another three years.
The water and the pollutants will be separated on site. The water will be treated, tested and then discharged.
The recovered hydrocarbons will be stored in a 2,270-litre tank and recycled.
"It's like if I took a sponge and poured water into the sponge and then you had to tell me how much water was in the sponge just by looking at it or poking it a few times. So that's very difficult.
"But we will have the recovery unit running for two years. The first year we expect to get most of the free LNAPL," she said.
Wharf is home to 26 fishing vessels
One of the challenges is carrying out a remediation at an active wharf.
Kraut Point is home to a fleet of 26 commercial fishing vessels ranging from small inshore lobster boats to the Atlantic Destiny, a large scallop factory freezer ship owned by Ocean Choice International of St John's.
There are numerous buildings on site, including two small electrical buildings, a waste oil storage building, a carpentry shop, a warehouse and a garage. In addition to the site buildings, there is also a large marginal wharf, a T-shaped finger wharf, and rock breakwaters.
Kraut Point is a designated small craft harbour owned by the Department of Fisheries and Oceans, meaning the department has to fix the problem even if the source remains a mystery.
- The Department of Fisheries and Oceans initially said it had spent $1.4 million studying the site. After this story was published, the department said there was an error and the number was not correct. It said was in fact $758,000.Jan 04, 2021 4:14 PM AT