Work Continues on Final Section of I-69 Project

McLaughlin Locators Tackle Underground Locating Jobs

Fri January 01, 2010 - Midwest Edition
Greg Ehm


The McLaughlin Verifier G2 utility locator offers four active frequencies for utility location as well as passive power, and passive utility modes. The unit can be used in the direct, indirect or coil clamp mode for inducing signal to the utility.
The McLaughlin Verifier G2 utility locator offers four active frequencies for utility location as well as passive power, and passive utility modes. The unit can be used in the direct, indirect or coil clamp mode for inducing signal to the utility.

When it comes to locating underground facilities, Greg Gissler and his team are relentless in their efforts to identify what lies below the surface. This team takes immense pride in their work and it shows as this division of INTREN (formerly Trench-it) is growing by leaps and bounds every year.

Gissler is the foreman of the locating department for INTREN based in Union, Ill. Founded in 1988, INTREN was in the right place at the right time: a project catapulted this company into the utilities installation business, and the rest is, as they say, history. Today, INTREN is recognized as a provider of inside, outside, underground and overhead electrical, gas and telecommunications services.

“I believe our success is directly tied to our honesty and integrity in completing a job,” said Howie Borst, project manager with INTREN. “Our employees take great pride in their work, and our clients can see that on the job site.”

Locating underground facilities is not an easy job these days. The vast array of lines in the ground has made underground installation projects challenging. This is where the One Call systems come into play. However, for many projects the One Call marks only identify utilities only in the easements, so project owners are left to find other alternatives when locating existing underground infrastructure on their private property.

“We do a lot of private locates for developers, as well as substations, fossil fuel plants and nuclear plants,” said Gissler. “We hire experienced locators with an average of 17 years in the industry and we don’t spare any expense when it comes to their safety and equipment.”

In fact, Gissler carries eight different locators in his truck alone, and depending on the situation he may use every one on a single project just to make sure his marks are as accurate as possible. On one project near Richland, Ill., Gissler used five different locators to find a 64 kV line, but it was worth the effort to make sure the contractor wasn’t going to hit anything.

“We are trying to isolate cables without everything being grounded to the same system, which is a challenge,” said Gissler. “Isolating a cable from one manhole to another can be difficult and direct connections aren’t an option in the substations and nuclear plants. So we take multiple approaches to give our clients the most accurate information possible. Nothing is 100 percent, but we get pretty close.”

No matter the project, INTREN encourages the customer to be on the job site during the locate process. This is not the case with some locating contractors, but INTREN believes in providing firsthand experience to its customers as they will have a better idea of what’s in the ground from this experience rather than just looking at the prints.

Customers provide a print of the area to be located and INTREN goes off the print, but it also works to make sure the prints actually match what’s in the ground.

“In some cases we find lines that aren’t noted on the prints,” said Gissler. “If we find something that’s not on the print, we add it and if the customer is with us, they can see the location of the lines firsthand.”

Pekin Project Presents Challenges

Gissler and his team recently completed one of the most difficult locating projects in his recent career. Midwest Generation is installing new scrubber units to its Powerton Generating Station located in Pekin, Ill. The original plant, constructed in 1928, generates 1.5 MW of electricity to meet the needs of 1.8 million households. The addition of the scrubbing units required Midwest Generation to relocate a railroad spur, lighting, and some buildings.

The initial portion of the project included an effort to locate the existing underground infrastructure. This was vital to the expansion as the new scrubber units required footings that would be placed up to 70 ft. (21 m) deep and due to the vast network of ducts and lines, the construction crew did not want to unexpectedly hit an active or inactive line or duct. The pilings were to be placed neck-to-neck and the construction firm had only a 6-in. (15 cm) window to relocate the ductwork if required.

Due to expansions and demolition projects on the site, there were no solid records of what lines were still active or inactive.

“Basically the ground was full of old and new communication, gas, electric and water lines and no one really had a solid blueprint as to which were active or abandoned lines,” said Gissler. “So we were given the prints and tasked with the challenge of going out into basically an empty parking lot to find this stuff.”

The project challenged Gissler and his team, but he soon discovered that the new McLaughlin Verifier G2 utility locator he purchased earlier in the year shined on this project. The Verifier G2 offers four active frequencies for utility location as well as passive power, and passive utility modes. The unit can be used in the direct, indirect or coil clamp mode for inducing signal to the utility. With depths up to 30 ft. (9 m) this unit can handle most locating jobs, according to the manufacturer.

Using prints and the McLaughlin locator, the team identified the underground facilities and staked each line and duct with color-coded lathe. Once the lines or ductwork were identified and all interference removed, a vacuum excavator was used to pothole and verify the actual line and location.

“We’d pothole and verify the edge of the duct runs in case they had to be moved 6 inches one way or the other,” said Gissler. “In the past, no one had bothered to pothole and verify if the lines were active or not.”

In one instance the team had to go into the basement of the plant, which was three stories underground, to identify a line that eventually led to a manhole outside. There was a substantial amount of interference, but the team found the line and followed it through the plant and back outside. Once outside, they discovered that the manhole indicated on the prints was not visible as it had been covered by an asphalt access road. So they dug down and found the manhole and verified the line.

“We gave our customer prints identifying the active and inactive lines and the surveyors knew the location of the ducts and what lines were in each duct,” said Gissler. “We probably spent almost two months on this project and it was one of the most challenging in my career.”

Training

INTREN has made safety and product training a priority. Every employee must complete a safety course before they are allowed on a job site. This includes gathering basic information regarding the safety protocols of the customer before arriving onsite.

In addition, Gissler will conduct random locate audits.

“I will show up on a site and randomly check the marks just to make sure the locator operator marks are accurate so when the underground contractor shows up there are no unexpected issues,” said Gissler. “In addition, I will just ride along with our team members and observe their locating technique. Normally they are doing everything right, but it’s just another check system.”

The crew also calibrates their equipment every morning to make sure the locators are working correctly. Each locator is tested to make sure it meets the manufacturer’s recommendations. Some units have a tendency to move out of calibration because the antennas move inside the unit. According to Gissler that’s not the case with McLaughlin.

“Due to the design of the McLaughlin locator the antennas are hard set into the unit and can’t move compared to our other units,” said Gissler. “We really don’t worry about the McLaughlin unit being out of calibration, which is nice.”

To Gissler it boils down to having the best equipment money can buy for his crew.

“It’s one of those machines that you might as well not go to work unless you have it with you,” said Gissler.