Helicopters Used in Stabilization of Remote Transmission Sites

Friday, June 14, 2013

By Jim Wahl, Wahl Marketing Communications

May/June 2013

Land and Water magazine, the magazine of natural resource management and restoration

W. James Construction crews were originally tasked to provide project-wide erosion control for the Sunrise Powerlink Project that would connect the SDG&E substation in El Centro, California, with their substation in Miramar, 120 miles of 500 & 230 kV power lines would link San Diego to the Imperial Valley, which has the highest concentration of renewable energy projects in California. The route, through multiple climate zones, and over rough, remote terrain, included 260 sites which were only accessible by air. As W. James Construction got into the BMP installation on the remote access sites, it made more sense for Warren James and his crews to help the grading contractor with the vegetation clearing as well as do the erosion control with one trip in and out. Necessity, being the mother of invention, James and his crews had to develop a way to rig Hydro-Mulchers® so that they could be carried by helicopter to these remote sites. For environmental reasons, nearly 7 percent of the construction was performed by helicopters and the project logged more than 30,000 flight hours. A rigorous, 5-year long environmental review and permitting process was required, and over 18 months of construction. 

"There are about 260 sites that are fly access only," recalls James. "So the task of prepping the sites for the foundation and erection crews turned out to be pretty complex. Our crew
consisted of an operator and three to four laborers. We would fly out to the sites with hand tools in the helicopter and bench locations on the site to set our other tools and equipment as the sites were too steep to set our equipment. Then we would have our fly boss, who was in the yard, get the helo in the air and send us our picks. These consisted of our orange toolbox, water buffalo, cargo net with waddles, and our chipper. We then cleared the tower site and helo landing pad as they were separate. Once the veg clearing was done, our crew would start installing BMPs as well as any environmental exclusionary fencing required for the site. At the same time, we would set up the Erickson Air-Crane to transport either the skid steer or dozer to the site depending on how much grading was necessary for the helo landing zone. So a finished site consisted of a brushed, BMP'd and fenced tower location, as well as a brushed, graded, BMP'd, and fenced helo landing zone. In the forest on high fire risk days, we could only use hand tools so we had to cut all vegetation by hand with loppers and handsaws and fly the brush out to the yard to be chipped. We also had to maintain the BMPs during construction so our crews were in these sites very regularly due to the steepness of the terrain and the spoils from the drilling activities. During the rainy season, we had a helicopter tied up nearly full-time doing maintenance. So when these sites needed seeding and stabilization to clear up the storm water permits, they approached us." 

James and his crews had rigging experience because they had previously figured out how to rig their chippers and tools so that it could be copter-carried to the remote sites. The sites contained a lot of rock, therefore, mowing decks and masticators typically would not work.

"We had good luck with Bowie machines," recalls James, "I especially like the performance and reliability of their gear pumps so we got two of the 300-gallon machines - the smallest ones they offer. We could not afford to get a seeder flown out to a site and break. This means unnecessary helicopter time we did not have due to the demand for helo support on line building activities. We had to be perfect the first time we went or we would not have met the deadlines." 

He took the Hydro-Mulchers® to the fabricator who had made all of the rigging required to fly out the other materials. The fabricator manufactured cages for the machines, and then James had them rated and pull-tested to ensure that everything was approved and safe before flying the equipment to the sites. Everything had to be pull tested to 125% and stamped to be air worthy. They had to factor max potential weight of the load with rigging, the added G-force load while in motion and swing, then times that by 1.25 to get the desired test load. 

There were contractor appointed air bosses in each yard that would check all stamps, certifications, and rigging tags to ensure safety. James sent all employees through a rigorous "rigging" training to be certified to hook up loads to the helicopter long line.

"This was the most critical part, as it is where human error could occur," James recalls, "so special attention andrepetitive trainings were common throughout the project." 

Once the rigging procedures were established and crews thoroughly trained, there was the helicopter availability issue to contend with. 

"This was our next challenge," James muses, "an A-Star which is the more readily available helicopter on the project could pick up about 3200 lbs., give or take depending on elevation. An empty Bowie seeder weighs around 2600 pounds with rigging. So when the K-Max (which can lift around 5000) was not available we had to fly our BFM, seeds, and two half full buffalos at 150 gallons each and mix on site. This took a tremendous amount of time we didn't have, but we understood the line building activities took priority over us. On days we had an A-Star only, we could only do a site or two due to long waits on materials and water." 

James estimates that on 95% of the sites, the lines were not energized.  "When we came in initially, the lines were de-energized so we would land the seeders right there (you can get within 5 feet of a de-energized line)," said James. "We would land, spray the tower site, and then have someone sign off on it before rigging it up to fly off to the next site." 

James and his crews repeated this task for about 200 of the sites. The other 60 were either on solid rock or had grown back to 70% so the permit could be closed without having to hydromulch.  

With so many sites to seed and two non-negotiable deadlines to meet, Warren James Construction purchased a total of 4 machines - enough for 2 crews. To ensure productivity, they set up a series of staging yards scattered along the project. At the staging yards, the crews would fill a machine with seed, hydromulch, tackifier, fertilizer, and water, and have it agitating.  A helicopter would pick up a fully loaded machine to deliver it to a jobsite and bring back an empty seeder that would then be refilled. This process would be repeated and seeders would be hopscotched from site to site. 

"We had nine yards scattered throughout the line," recalls James, "they were strategically placed so we had minimal major road crossings and could get to every site.  We still needed a good deal of traffic control to cross some roads and public use areas which had to be coordinated between crew, helo and traffic control crews."

The seed mix varied from section to section.  For the majority of the project, James used Profile Products' Hydro-Blanket® at 2500 lbs. with a native seed mix per section. The seed mixes could span anywhere from 10-30 tower sites and were collected by S&S Seeds.

"We must have had 200 bags of seed we had to sort through and stay up on as our locations changed every day," recollects James. "If we had to change sections in a day, we had to do a full clean of the seeders before we could move on to avoid cross contamination of the seeds. On some sites in the desert, we used M-Binder with no seed or BFM for stabilization only."

"There were two really important deadlines throughout the project," recalls James. "We had to be out of the bighorn sheep area by New Year's Eve and out of the Golden Eagle areas a month later. As a result, all activities were occurring at once in the same place. We would be hydromulching sites, and they would be pulling wire over us."

"We accomplished from 1 to 5 sites a day," James continued. "The linemen were using the same helicopters we were so when they were stringing wire, or doing their dead-ending and clipping, we had to sit tight. It took us about 3 ½ months to get it all done."

Weather, specifically fire threat levels, played into logistics as well as the production time frame.

"If it was a high fire day, we had to stop by 1 o'clock," recalls James. "On an extreme fire day - which we encountered a lot - we could not work at all."  When that happened, in addition to daily delays, there were logistical issues to contend with.

"If we were scheduled to seed forest sites and found out the night before the fire level was an EV," said James, "we would have to scramble early in the morning to load all tools and equipment on our trailer and move to a new yard in order to stay productive.  As soon as the PAL level lowered, we would mobilize back as the forest was priority."

"We would have materials stranded on certain sites," mused James. "We had a lot of hurdles to overcome. It certainly was not as simple as showing up to see how many sites you could get done in a day."

When they were given the opportunity to work, however, James and his crews were prepared. Utilizing high-tech and non-standard methods like transporting Hydro-Mulchers® via helicopter - to tried-and-true methods like manual labor for clearing, they provided erosion control for remote sites, thus bringing solar power from the desert to homes near Miramar, California. With 1/3 of all utilities slated to come from renewable resources, hopefully, more solar projects will be built - if so James and his crews are ready, willing, able - and now, experienced.