Hydro Excavation Mud – Pipeline Integrity Test
Case Study
Challenge
Pipeline integrity testing often requires hydro excavation to expose a segment of pipe for inspection. The resulting hydro excavation muds are often a regulated, challenging to dispose of and in some cases, contaminated. In 2015, MetaFLO licensee KBL was contracted by a major Canadian pipeline operator in Alberta to provide the solidification and disposal of 200 m3 of this waste.
Solution
KBL provided two shale bins placed in parallel at the job site. The hydro excavation trucks offloaded into one of these tanks. With the heavier solids settling at the bottom of the tank, the surface water was pumped to the second tank. The heavier mud was mixed with MetaFLO’s MF006 solidification reagent at a dose appropriate for the whole load. The surface water was then returned to the first tank to finish mixing.
Result
As seen in the photos below, as a result of the MF006 treatment, the hydro excavation material on the left was transformed to the dry, earth like finish in the right photo. This solution required no in-ground sumps, provided optimal efficiency for expensive hydro excavation trucks and low cost disposal options for solid material. Also, the 1% doseage required for solidification with MetaFLO’s reagent, results in a much smaller quantity than would be produced by sawdust or wood chip bulking methods. The client also reduces activities that generate a carbon footprint and mitigates safety and environmental risks associated with shipping large quantities of liquid waste.
Owner: Vale Canada Ltd.
Contractor: Tervita Corp.
Distributor: Di-Corp
Vale owns and operates a mining site in Northern Ontario, Canada. Through their mining and refining activities they produce a sludge waste by-product. The clients were in need of an efficient excavation and transportation solution to get this sludge to their off-site landfill.
End of September 2018 - Mid October 2018
During the bidding process, MetaFLO was engaged to provide an optimal blend and dosage rate to achieve the solids criteria required for excavation and transportation of the sludge. Using analytical data, MetaFLO estimated a dosage rate of 1.1% by weight (based on a high moisture content). Large mixing bins were recommended for increased surface contact and efficiency during the bucket mixing process. No sample was available at this time.
Tervita Corporation utilized MetaFLO reagent to solidify approximately 4,000 m3 of sludge. Two 35m3 bins were staged on site and were loaded with a composite of “heavier” and “lighter” sludges. The originally estimated dosage rate was accurate as actual treatment averaged approximately 30lbs of MetaFLO MF006 reagent per m3 of sludge. All material was safely shipped to Vale’s off-site landfill. The job was completed on time.
