Wellsite Remediation in Fort St. John, BC | In-Situ Chemical Oxidation (ISCO) Case Study

Case Studies

Wellsite Remediation in Fort St. John, BC | In-Situ Chemical Oxidation Case Study

Project Details:

Location:

Wellsite – Fort St. John, British Columbia

Site:

Oil and Gas Spill Site

Date:

2019

Present

Contaminant of Concern:

BTEX, LEPH, HEPH, PAH’s

Impacted Media and Volume:

2,700 m3 impacted soil and groundwater

Project Tasks:

Remedial Planning, Detail design, Procurement, Injection Well Installation, Blending and Field applications

View Project Images & Details →

The Problem:

Former helicopter fuel storage area overlying saturated shallow sands. Fuel (BTEX) contamination within the soil and dissolved in groundwater. Due to shallow groundwater, depths of impacts, and coarse-grained lithology, a winter injection program was developed.

The Approach:

Conducted a pilot test at the Site prior to full scale to ensure adequate distribution and determine the most appropriate radius of influence (ROI). Full scale in-situ chemical oxidation (ISCO) program was then conducted based on a 5 meter injection radius of influence. Establish health and safety protocol and site logistics for handling oxidizer.

Installed 42 injection wells and injected 60,000 litres of blended 15% EHP (enhanced hydrogen peroxide) oxidant. Blending is site specific following TRIUM’s ChemOx® process.

The Results:

Significant reduction in non-aqueous phase liquids (NAPL) in the groundwater
Significant reduction of overall plume size
Very short timeframe of treatment
Highly cost effective compared to traditional remedial options
Excellent reductions noted with injection distributions exceeding planned performance

Closure-Based ISCO Remediation at a Power Generation Plant in Northwestern Alberta

A closure-based in-situ chemical oxidation (ISCO) program was implemented at an operational power generation plant in Northwestern Alberta to remediate F2 and vinyl chloride contamination in 300 m³ of impacted soil. Site constraints, including existing infrastructure and a lack of groundwater, required a 0.75-meter injection radius for increased contact certainty. Over five days, 37 injection points were advanced, delivering 32,800 liters of 12% EHP (enhanced hydrogen peroxide) using TRIUM’s ChemOx® process. The treatment successfully met applicable soil quality guidelines within a short timeframe, with no disruptions to facility operations.

Gas Station Remediation Southern Alberta: ISCO & SVE Treatment

A closure-based in-situ chemical oxidation (ISCO) remediation was conducted at a former gas station in Southern Alberta to address BTEX, F1, F2, and PAH contamination in 6,630 m³ of impacted soil, bedrock, and groundwater, including off-site impacts beneath residential properties. Due to infrastructure constraints and vapour risks, a Remediation Train® approach was implemented, starting with a soil vapour extraction (SVE) and air sparge system, followed by a ISCO program with a 3-meter injection radius. Nested injection wells targeted various depth intervals, with careful scheduling around residential activity. Over 45 days, 1.6 million liters of 10% EHP (enhanced hydrogen peroxide) was injected using TRIUM’s ChemOx® process, achieving daily blend volumes of >35,000 L. The treatment successfully met regulatory groundwater quality guidelines, managed vapour risks, and was recognized as an industry-leading process by consultants, with no negative impact on the community.

Case Study: