Drill Waste Management for Gas Distribution Upgrade

Case Study

Drill Waste Management for Gas Distribution Upgrade

Challenge

In 2015, a major Canadian natural gas distribution company had to perform construction operations to upgrade its existing distribution system. To mitigate the disturbance of the surface level roads and natural habitats, the proponent utilized horizontal directional drilling (HDD) technology. Twenty large bores (36″ and 42″) were planned for this project.

HDD operations were anticipated to generate 60,000m3 in need of drill waste management. During some portions of the project, there would be five drill sites operating concurrently.

Much of this project took place in an urban centre along a utilities corridor providing limited space for waste solidification operations.

This waste stream is classified as ‘liquid industrial waste’ by Ontario regulations. The cost to transport and dispose of this waste as a liquid is very high. The carbon footprint and safety risk associated with the transportation of this volume of liquid was also very high.

As a result, the project proponent determined the lowest cost, disruption, risk, and carbon footprint could all be achieved with on-site liquid solidification and developed a scope of work with zero liquid waste to be shipped off site.

Solution

MetaFLO’s licensee, Allstream Waste Solutions (AWS), was awarded the contract to provide drill waste management on site. AWS mobilized to each job site with multiple pieces of equipment including two MetaFLO LMS 3  mixing units, semi-solid mixer and dozens of open top bins custom designed for managing heavy drill cuttings.

The lighter drill fluids were to be solidified at very low dose rates using the MetaFLO LMS 3 units and MetaFLO’s proprietary reagent MF002. The heavy drill cuttings were to be mixed with a semi-solids mixer or the bins (seen below) with MetaFLO’s MF006 at even lower dosage rates due to the high quantity of solids in that waste stream.

AWS managed all environmental analysis and final disposal of solidified waste. Based on individual, pilot hole analytical results, final disposal sites were chosen by AWS and approved by the project owner. Once solidified, the waste drill fluids met criteria of clean fill and was used in a rehab project further reducing the environmental impact of this project.

Result

It is estimated our client achieved greater than a 30% cost savings in the management of  this waste stream. The compact design of MetaFLO equipment, efficient site operations and large volume, above ground containment capacity provided by AWS meant that no in ground sumps were required and no off site transportation to was necessary. AWS’s equipment and vehicle inventory was able to handle many sites simultaneously. Finally, the MetaFLO system eliminated thousands of truck hours drastically reducing the carbon footprint of the waste management operations.

Cabonne Shire WWT Lagoons

Key Stakeholders:

Owner: Vale Canada Ltd.
Contractor: Tervita Corp.
Distributor: Di-Corp

vale-tervita-di-corp

Challenge

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.

Date

End of September 2018  -  Mid October 2018

Solution

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.

Result

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.