A Lumber Mill located in British Columbia was planning to excavate an area on their site and wanted to ensure that there were no utility lines that could be damaged as part of the work. Our job was to perform a utility locate on the area, mapping the lines in a report so the client could ensure a safe and risk free excavation.
The reason for the site excavation was that two parallel air lines which blow wood chips onto a conveyor were broken, costing the company thousands of dollars a day in lost production.
With heavy lumber equipment and trucks driving through the area next to the mill there was enough pressure to crack the buried airlines, causing a loss in pressure which put the lines out of commission. In order to repair the lines the client needed to excavate down to the pipes and repair the broken section.
Utilizing GPR and EM Locating technology, a GeoScan technician was able to identify and mark out all existing services in the area. GPR was easily able to locate the two air lines which ran 0.5m apart in parallel.
While exploring an access put for the lines in a different part of the property, our technician discovered a communications conduit running along with the air lines. EM locating was used to trace this line through the area that was to be excavated. In addition we detected another unknown line nearby and traced out a compressed air line that was contained within the nearby building.
All known utilities in the area were located and the client was able to proceed with the excavation knowing exactly where all the piping exists.
This job perfectly highlights the difference between an expert technician and other companies who would provide a base level service. Our GeoScan technician wen above and beyond by investigating the nearby pit and discovering the communications line. Had this not been detected this would most likely have been damaged during the excavation, causing additional unexpected costs to the clients.
Underground Oil Storage Tanks are commonplace in properties across Canada and, while they previously used to heat properties, they are now a risk and should be removed.
GeoScan utilize Ground Penetrating Radar (GPR) and other locating methods to non-destructively locate underground tanks, allowing for their safe detection and removal.
We get a lot of questions about oil tanks and locating, so we spoke to our technicians to provide answers to these frequently asked questions:
What are Underground Oil Storage Tanks (UST)?
Underground Oil Storage Tanks were commonly used to heat houses prior to the 1970’s and can either be above ground or buried. As more effective heating methods are introduced, tanks are becoming obsolete and must meet specific requirements or be removed.
If your house was built prior to the 1970s and you did not receive any information from the previous owners regarding the presence of an Underground Oil Storage Tank, then you should have your property scanned.
Where would I expect to find an oil tank on my property?
Oil tanks are approximately 6 feet in length and 3 feet wide. They are usually found within 2-3 meters from the house and 3 feet below the surface of the ground. Keep in mind that if your house underwent any renovations (additions), then an oil tank may exist beneath your addition not your house.
How do I know if an oil tank exists on my property?
There are many visual signs that may indicate the presence of an underground oil storage tank on your property. The presence of vent pipes and fill pipes are big giveaways that there may be an accompanying oil tank nearby. Cut off supply lines in the basement are also signs of an oil tank.
Why would a property owner want their oil tank removed?
What happens if a tank is found?
If a tank is found on your property it can be removed by a tank removal company. They will obtain a permit if one is required in your municipality. They will then arrange for a pump truck to remove the contents of the tank if it is not empty. After removing the tank, the soil will be examined for contamination and an Environmental Consultant may be required. If the soil is not contaminated, the tank removal company will backfill the void and may even seed the soil for you. You will then receive a report from the tank removal company stating that an Underground Oil Storage Tank was removed from your property. A copy of the report will also be sent to your municipality.
What happens if a tank is not found?
If a tank is not found then you will be given a report stating that your property was scanned using Ground Penetrating Radar and that NO Underground Oil Storage Tanks were found on the property surveyed.
For more information on underground oil tank locating, get in touch with one of our technicians.
GeoScan travelled for two days to reach a remote northern BC exploration mining camp in order to complete a Subsurface Utility Engineering job at the base camp.
Following a survey of the lower staging camp, our technicians flew by helicopter to the upper camp to complete an additional locate survey. The purpose of the job was to improve safety and future planning at both sites.
The client had been experiencing multiple utility strikes when performing upgrades to their current systems due to poor documentation. The only documents that existed were from the planning stage and could not be relied upon to safely carry out the work.
While planning a future expansion of the multi-generation camp they realized it was necessary to accurately locate and map the utilities in order to prevent damage and injury. Due to the remoteness of the area hospital care could take days to reach therefore the dangers form hitting a utility are increased dramatically.
GeoScan travelled to the two sites to perform the locate and survey to a SUE Level B Standard. This process involved locating all utilities in the both the upper and lower camps then surveying the area to create an accurate as-built map of underground infrastructure.
This map will then be used to plan future upgrades as well as prevent dangerous utilities strikes, allowing the client to save time and prevent injuries.
GeoScan were called to conduct a utility locate survey by a client installing a storm water force main in order to transport fluids through a 400m trench.
Engineers had designed a route for the 400m pipe without taking into consideration the possibility of utilities crossing the proposed trench line. GeoScan were contacted to assess the site and determine whether the route of the pipe encountered any existing or old utilities, in addition to any potential subsurface obstructions that may interfere with the work.
BC One Call and GIS were unable to provide much information for the utilities on the site, so we were challenged with conducting the survey based on utility surface features, such as manholes, power drops, valves and hydrants in addition to performing utility locate scans on the trench line.
Our GeoScan technicians utilized Ground Penetrating Radar (GPR) and Electromagnetic Locating to analyze the site and determine if there were any anomalies crossing the trench that would interfere with the proposed pipeline.
After conducting the GPR and EM surveys we also carried out a site walkthrough where we found an additional electrical duct bank where the cables had been cut, meaning that the EM was unable to detect them. Carrying out an additional scan we discovered more conduits crossing the trench.
As a result of the utility locate the pipeline trajectory is now being re-evaluated by the engineers in charge of the project. Had the client not booked the locate they would have hit multiple utilities causing significant disruption and costs to their project.
Utility Locating is the process of identifying and labelling underground public and private utilities and can include storm, sanitary, water, electrical, communication, fibre optics and more.
Onsite utility locating is necessary as existing maps, as-built drawings and One-Call information are not accurate enough to ensure proper clearance. The ASTTBC Registered Utility Locator (RULT) Certification Program is the first of its kind in BC, and is designed to recognize the competencies of locators who work in various industries and to deliver an enhanced level of public safety.
Confidence in locating reports
Utility Locating uses both Electromagnetic Technology and Ground Penetrating Radar to accurately identify and locate the position of underground utilities. These technologies are non-destructive and provide real time results, however, the technologies themselves are unregulated, meaning anyone could claim to provide the service. That’s where the RULT certification comes in.
ASTTBC Registered Utility Locator Technicians provide the ground disturbance community and others with the confidence needed to complete projects efficiently and safely. When retaining utility locating services, hiring a registered utility locating technician means you can be sure that the information reported is accurate, allowing you to proceed with the project and be confident making informed decisions.
Accountability, compliance and safety
A Registered Underground Utility Locator Technician (RULT) is a person who understands and applies all the principals of utility location including the process verifying, identifying and labeling public and private utility mains and other services located primarily underground.
These utility mains locates will verify existing record drawings or official as-built drawings provided by the municipality, property owner, or those obtained through the BC One Call system. A Registered Utility Locating Technician must work in accordance with regulations, standards and techniques applying to each work site in order to best ensure the health, safety and wellbeing of all workers, the public, the adjacent properties, the utilities and the environment.
Hiring a Registered Utility Locating Technician
At GeoScan we offer a range of utility locating services, from Oil Tank Locating and Utility Locating, to Subsurface Utility Engineering.
In order to provide the highest level of service and lead the utility locating industry we ensure that our staff are all ASTTBC Registered Utility Locator Technicians. This ensures that our clients receive the highest level of service and the assurances they need.
For more information on Utility Locating and RULT, get in touch with one of our qualified technicians.
There is a lot of information to cover when it comes to utility locating and the technology used. We often receive similar questions from clients so we have put together some FAQs to help point you in the right direction for your project!
How do you locate utilities?
We use both electromagnetic technology and ground penetrating radar to accurately identify and locate the position of underground utility services. This technology is non-destructive and provides real-time results. The location of utilities are clearly marked directly on-site allowing you to dig with confidence!
Is GPR a safe technique?
Yes. While “Ground Penetrating Radar” may sound like a hazardous technique, it is extremely safe and emits roughly 1% of the power of a cell phone.
How deep can you locate targets?
Penetration depth depends on the material being surveyed and the antenna being used. A lower frequency antenna is able to locate deeper targets, but outputs results at a lower resolution.
Drier materials such as sandy soils return excellent survey resolution, whereas heavy clay-based soils are difficult to penetrate. In some situations scan depth may be limited to a few feet within clays, whereas pipes within sandy soils could be detected at depths up to 30 feet.
How does GPR work?
A GPR system consists of a transmitting antenna and a receiving antenna. The waves emitted from the antenna penetrate the ground and reflect off buried objects and return to the surface, where they are then detected by the receiving antenna.
By measuring the travel-time of the wave we are able to assess the size, shape and depth of the target within the subsurface.
What is Electromagnetic Locating?
Electromagnetic Locating uses a transponder that transmits an extremely low voltage AC current onto a conductive material (ie. a pipe that is steel or polyethylene with tracing wire attached to it). The underground utility line can then be accurately located and traced with a wand-like receiver that detects the EM fields that have been created around the utility line.
When you find underground utilities, can you determine what type of utility it is?
Yes, in the majority of scenarios. We do this by tracing the utility, starting from an identifying feature present on the surface, for example, valves, meters, control boxes etc.
Only in cases where we are unable to directly connect to the utility, or where there are no surface features present, are we unable to identify whether the piping is gas, water, storm etc. Additionally, we are able to provide the elevation of the utility and reference it with the as-build plans to confirm that they are without error.
What is the difference between GPR and X-Ray?
For a detailed explanation of the difference between GPR and X-Ray, please see this article.
What is a Registered Utility Locator Technician (RULT)?
To lead the utility locating industry and push for regulation and accreditation, GeoScan have assisted the Applied Science Technologists and Technicians of British Columbia (ASTTBC) in pioneering the newly developed Registered Utility Locator Technician certification.
GeoScan are currently the only locating provider in BC with Registered Utility Locator Technicians (RULT). Find out more here.
How much does utility locating cost?
The cost of utility locating mainly depends on the size of the scan area. Get in touch for a free quotation.
You don’t have an office in my location, do you travel?
We have offices in Vancouver, Vancouver Island, Montreal, Quebec City and Toronto and frequently travel to other regions and provinces to carry out work where required.
If you have a project in mind our technicians can discuss pricing for specific travel time and provide you with a quotation.
Get in touch for more information.
GeoScan were recently contracted to provide pre-design services for a tenant improvement project prior to the design pf a restaurant.
A Vancouver based architecture client was in the process of designing a restaurant and wanted to ensure that their design would meet all required regulations and would not cause any issues with the existing structure.
The site was approximately 5,000sqft and includes the restaurant, back of house, washrooms, and bar areas.
GeoScan were called to conduct a Pre-Design concrete scan of the entire area in order to map any potential conflicts for the design team. We used the Vuit 3D Lasar Scanner to produce an updated as-built drawing, which included all in-slab infrastructure.
The information was provided in the form of a standard report, along with 3D point-cloud data. This data can then be loaded into AutoCAD, allowing the team to design a conflict-free space. By conflict we mean in terms of things such as structural slab bands, post-tension cables, teck cables, conduits, and water lines etc.
Scanning prior to the design of a project and having all of this detailed information means that you can guarantee there will be no need for a redesign, which commonly cause major delays and incur greater project costs. It also allows the team to explore the location remotely through our 3D Virtual Walkthroughs, making decisions much faster and reducing the need for further site visits.
For more information on how our Pre-Design Surveys can help your project, get in touch with one of our technicians.
During a number of recent projects our technicians have discovered very shallow post-tension (PT) cables on job sites. This is a huge issue and can be incredibly dangerous, as well as resulting in costly repairs.
Our technicians have reported finding cables up 7mm below the surface, which is usually unheard of. These cables are under massive stress and should they be hit, or cut in anyway they can explode out of buildings and through the concrete itself!
What is a post-tension cable?
Post-tension cables are used in concrete construction to add strength to thin and long slabs. Concrete has very high compressive strength but lacks in tensile strength, which is where post-tension cables and rebar come in.
The cables themselves consist of steel wires within a plastic sheath which are then tensioned after pouring in the concrete. This vastly increases the load-carrying capacity of the structure meaning that less concrete can be used, and allows for fewer beams, longer spans, and thinner slabs. It is used across a wide range of structures including apartment buildings, office buildings, and bridges.
Dangers surrounding post-tension cables
When cables are drawn tight they are under thousands of pounds of pressure. If theses cables are cut, nicked, or compromised, they can rip through the concrete and cause serious injuries and damages.
Cables are usually below a layer of rebar, however, recently our technicians have reported finding PT cables at very shallow depths. This causes a lot of issues as contractors do not realize they are laid so shallow. Luckily we are able to detect them and allow those on site to avoid them.
Scanning concrete for obstructions and hidden objects
During construction there is often the need to cut or core through the concrete slab, along with the need for anchoring for pipes or walls. It is incredibly important to avoid hitting PT cables when carrying out this work.
GeoScan are Canada’s leading experts when it comes to concrete scanning and are able to scan and identify obstructions below the surface and differentiate PT cables from other in-slab targets such as rebar or conduits. Using our Xradar™ Concrete Scanning methods, we are also able to determine the depth of objects and advise on the best course of action when carrying out work.
For more information on concrete scanning, or what we are currently finding when it comes to post-tension cables, get in touch with one of our expert technicians on (604) 436-7226.
GeoScan Subsurface Surveys is pleased to announce that we are the only provider of Xradar™ Enhanced Concrete Scanning on the West Coast.
Xradar™ is an advanced imaging capability utilizing GPR technology which allows you to map and locate objects that conventional GPR cannot. Xradar™ allows you to scan the ground for subsurface objects and is commonly used in applications across construction, archaeology, geophysics, and the military.
What is Xradar™?
The scanning process works by sending high-frequency electromagnetic waves into the ground from a transmitting antenna. These waves are reflected back as they bounce off objects, which forms an image of the subsurface.
This method can be used on a wide range of surface materials including rock, soil, ice, water, pavements, and other concrete structures. Unlike conventional GPR, Xradar™ can also distinguish between multiple layers of steel reinforcement, locate objects hidden below steel, as well as accurately measuring the size and depth of steel reinforcement.
Why choose Xradar™?
While conventional GPR is an unregulated industry, Xradar™ technicians are highly trained and have an advanced understanding and knowledge, meaning they can accurately interpret the data to form a clear picture of the subsurface.
When used for scanning concrete the accuracy and range far outshines that of any other method, while scanning errors are reduced to less than 1%, compared to the 25% typical for the industry.
Using Xradar™ saves you time, prevents injuries, and vastly reduces costly errors that can happen as the result of poor scanning.
GeoScan Subsurface Surveys and Xradar™
GeoScan is proud to be able to offer Xradar™ Enhanced Concrete Scanning Services as we continue to strive to deliver the highest level of service to our clients. As such, we are the only company on the West Coast that guarantee our concrete scans. This means that you can have full confidence in our services, allowing you to focus on your project without any costly and time-consuming errors.
Xradar™ is based in Toronto and Montreal, and GeoScan are excited to bring this industry leading service to the West Coast as the sole provider.
For more information on Xradar™ and the services we offer, get in touch with one of our expert technicians on (604) 436-7226.
GeoScan were recently hired by a leading engineering company to perform a geophysical survey of a suspected waste dump.
An area south of Victoria on Vancouver Island was suspected to have been used as an illegal dumping ground. Approximately 6,700 square meters, the area required an Electromagnetic Conductivity Survey to determine the presence of buried waste, and therefore confirm the company’s suspicions of illegal dumping.
A GeoScan technician performed an Electromagnetic Conductivity Survey of the area in order to test for areas of high conductivity and metallic disturbance.
This technique is commonly used to identify subsurface features, areas of high or low conductivity, and areas of high magnetic disturbance. The data was processed to create two differing colour-coded maps of the subsurface, showing conductivity data in MilliSiemens per Meter (mS/m) and In-Phase (magnetic) data in Parts Per Million (PPM).
The scan showed the main concentration of conductivity in the southern part of the area, confirming the presence of buried waste. The eastern area of the survey also displayed some responses, although with evidence of existing dumping, scrap metal, and other items scattered throughout the survey area on the surface, this is suspected to mainly consist of surface metal.
Although Electromagnetic Conductivity was used for this site, we could also have used a Magnetometer which draws accurate results when determining old, buried material.
For more information on our geophysical services and Electromagnetic Conductivity Surveys, get in touch with a GeoScan technician.