Along Vancouver's prestigious Point Grey Road, owners of three multi-million dollar luxury homes lining the ‘Golden Mill' have discovered the benefits of going geothermal, and, although each home uses it differently, they all chose the same drilling technology for the installation - namely sonic.

"This is the third house on the same street," says Jackquie Grant, project manager at Sonic Drilling, a Canadian company that contracts out a fleet of rigs with patented sonic drill heads - developed by engineer Ray Roussy, who was the first to successfully commercialise sonic drilling. "This latest project is a geothermal installation for a new house and swimming pool; we're actually putting the drill holes and geothermal loops under the pool."

She adds: "With the remaining two houses, one used geothermal to heat a long driveway and parking lot, while the other used it for a large garage with some high-end cars."

In deep water

Most geothermal installations require holes to be drilled to a depth of around 300ft (91m). With challenging soil conditions in the area, many conventional rigs get stuck or jammed, which slows down drilling considerably and, in some cases, makes it impossible. Due to Vancouver's location near an ocean and the end point for a number of rivers, it's not uncommon for rigs to encounter everything from sand and clay to large boulders in the same hole, and many times Sonic Drilling has been called in as a rescue rig to finish a project.

Unfortunately, an incident involving another street of luxury homes in Vancouver has left a bad taste for residents, when an inexperienced drilling crew breached an underground aquifer.  

As the Vancouver Sun newspaper reported, in September 2015, Feng Lin Liu was building a mansion on his C$3 million (US$2.4 million) vacant lot, which is surrounded by other luxury homes.  A contractor who was hired "on a handshake" to build Liu's home hired a team of drillers, who were unlicensed, unbonded and uninsured, to install a geothermal heating system.  The drillers - also hired on a handshake - used traditional drilling technology and accidently pierced a pressurised regional aquifer. 

Situations like this can happen when drilling companies sense opportunities during an economic boom but lack the skill and local knowledge to complete the job properly. In this case, the crew had shipped their drill rig all the way from Italy to Canada but, in addition to neglecting to obtain permits and obey regulations, they also caused one billion litres of water to run free, which resulted in the evacuation of 12 homes (two remain evacuated) due to fears of a sinkhole developing beneath them. 

In the end, the cost of this colossal blunder hit C$10 million and the drilling crew left Canada to escape responsibility. While neighbouring homeowners watched their housing values plummet, the city of Vancouver struggled to stop the flow of water and to collect on the cost of repair from the homeowner.

According to city officials, this is likely the first instance of a high-pressure aquifer being ruptured in a high-density urban environment. Two years after the incident, the city has not been able to completely stem the flow of water, noting that the incident has presented numerous challenges and has required extensive study and monitoring. 

This incident could have been prevented if sonic drilling technology had been used. 

"Because we case the hole at the same time as we drill, it's very easy to deal with positive pressure aquifers if you're using a sonic rig," says Roussy, president of Sonic Drill Corp. Roussy holds dozens of sonic drilling-related patents including ones governing geothermal installations using a sonic drill.  "We know how to contain artesian flow. We've been doing well installations in the Vancouver area for more than 35 years.

"The worst thing that crew did was take their pipe out; they should have left it in," he adds.

For geothermal and other applications

Sonic drilling technology, which is now used across six continents around the world, has a couple of unique aspects that makes it suitable for geothermal installations in difficult terrain.

First, it is three to five times faster, and it can drill easily through mixed soils. Secondly, it can drill, case, loop and grout - all in one operation.  This is a critical function in containing artesian flows.

"Without question, sonic drilling technology is the best choice when it comes to geothermal installations," says Roussy, who has seen his award-winning technology used in multiple applications across the world, from exploring for diamonds in Africa and searching for gold in Peru to revealing glacial secrets in Canada and expanding an underground New York subway in the US

More recently, Roussy has been partnering with drill manufacturers such as Eijkelkamp SonicSampDrill and Dando Drilling International to create easier access to his technology for the European market.  His sonic technology is also licenced in Asia to Japan's Toa-Tone Boring to service buyers there.

"Instead of forcing companies to ship a drill head across the Atlantic or Pacific, we're working with local companies that we respect and trust to service the markets in their areas," explains Roussy.  "This saves customers money and time in shipping a sonic drill to their location."

In addition to expanding its global partnerships, Roussy says that, in the future, he expects to see his sonic drilling technology increase its market share in most drilling applications, but especially in the construction sector where it holds much promise.