Salt Mine Core Drilling – With Bears!
Every year between March and April in Louisiana, the black bear begins to emerge from its dormancy. Louisiana black bears are large mammals with black fur and rounded faces. Adult males weigh in at about 300- to 400-pounds, and females weigh substantially less, typically 120- to 200-pounds. Even so, these are not creatures you would want to find yourself face-to-face with unprepared. The bears typically breed through summer and begin to prepare for their dormancy through autumn. Louisiana is home to an estimated 500-800 bears, classifying them S2, or imperiled. Still, it is more than possible to encounter them, and CSDA member Aggregate Technologies found themselves eye-to-eye with a few of them in November of 2020.
In Southwest Louisiana, GC Coastal Contractors reached out to CSDA member Aggregate Technologies to renovate a deteriorating salt mine. Aggregate Technologies has two locations, one in Houston, Texas and another in Baton Rouge, Louisiana. They are well-known for their highly skilled operators and extensive fleet of equipment for complex jobs. This assignment was already complicated because they were commissioned to core drill 91 holes into the mine shaft, ranging from 18-inches to 40-inches deep. This job would require safety harnesses for all operators to ensure no one is dropped into the 1,600-foot shaft. However, this job had a couple of extra risk factors: a massive hurricane sweeping through the gulf and displacing the local black bears.
The operators had to figure out a plan for drilling the 91 holes of varying depth and 1-inch width into the rebar reinforced concrete into the mine shaft. Once the job was surveyed, they quickly realized that the mine shaft was far too small to fit the base of the tower, and thus made the decision to slab saw the mine shaft to widen it. Using a Husqvarna 7000 slab saw with DDM Concut diamonds blades, Aggregate operators sawed roughly 65-feet around the opening, about 10-inches deep. Once the mine shaft was widened, operators used safety harnesses with integrated fall limiters, also known as yoyos, secured to a beam to safely lower themselves and the necessary equipment into the mine shaft. Then, the core drilling could commence.
Along with the safety harnesses with the yoyo tie-offs, typical PPE including hard hats, safety glasses and gloves were worn during this job. The scaffolding was also constantly inspected to ensure it was stable and safe. Without harnesses, the operators risked a daunting 1,580-foot drop to the bottom of the mine, a fall no one wanted to risk. The black bears in the area added another obstacle. Bears are more likely to be seen this time of year as they get ready for hibernation, and in this case, Louisiana had just been ravaged by Hurricane Zeta, upheaving most of the wildlife in the area. One operator said a bear approached within 60-feet of him, and when it stood upright, was eye level with him!
Working at the top of the mine shaft, workers used Shibuya core drills with Diteq core bits to drill the holes in the desired locations into the hard concrete. The holes were then cleaned and roughed. After the holes were prepped, they were filled with Hilti epoxy and 7/8” rebar was inserted. Aggregate had three days to complete their portion of the renovation but managed to complete it in only two. David Rogers, the project manager for Aggregate Technologies, said he was extremely satisfied with the results of the project. “All of the operators did amazing work to get the project done on time with zero incidents,” stated Rogers.
If you happen to be wondering what to do if you are encounter a bear, Black Bear Project Leader Jaime Sasjecki advises, “Never run from a bear. Don’t approach a bear – just quietly move away and leave the area. However, if a bear does approach you, make yourself look big, make loud noises, clap your hands and continue to back away.”
CSDA contractors are used to being called to complete challenging jobs. Aggregate’s reputation for problem-solving, excellence and quality work ensured that they were selected for this job and will secure them future work, especially with their new-found experience with bears!
Aggregate Technologies has been in business an impressive 23 years and a CSDA member for eight years. They have 35 staff members, 31 trucks and two branch locations.Their physical locations are in Houston, Texas as well as Baton Rouge, Louisiana. Aggregate has an impressive resumé, with their list of skills including concrete breaking and removal, GPR scanning, core drilling, electric sawing, hydrodemolition, pile cutting, robotic demolition, slab sawing, wire sawing and wall sawing.
CSDA Contractor: Aggregate Technologies
Contact for Story: David Rogers
Methods Used: Core Drilling, Slab Sawing