Site Remediation and Reclamation

Soil Vapour Extraction (SVE)

Relevant Contaminants:

  • Volatile Organic Compounds (VOCs)
  • BTEX, F1 Components
  • Volatile Hydrocarbon Fuels (i.e. gasoline, condensate)
  • Chlorinated Compounds

Soil Vapor Extraction(SVE) is an in-situ remedial technology which is used to apply a vacuum to the vadose (unsaturated) soil zone which has been impacted by contaminants. The technology allows for the controlled flow of air to remove volatile compounds from the soil. Because the technology involves the continuous flow or air through the soil, it will often promote in-situ biological degradation of less-volatile compounds or residuals.

Through the installation of either vertical or horizontal wells above the water table, a vacuum can be applied to the wells to pull the vapors out of the ground. Depending on the project location, the exhaust air from the SVE may require treatment to eliminate possible harm to the public and/or the environment.

Remediating a site using SVE may take several years, and is based on the following factors:

  • Size and depth of the contaminated area
  • type of soil and moisture conditions
  • Chemical properties
  • Concentration of the contaminant

In instances where complete remediation is not possible, SVE can effectively mitigate the risk of volatile contaminant migration.

Nichols Environmental has installed and maintained numerous SVE systems. The systems have been installed as a stand alone remediation tool, or they have been used in conjunction with other remedial technologies.

Air Sparging

Relevant Contaminants:

  • Volatile Organic Compounds (VOCs)
  • BTEX, F1 Components
  • Hydrocarbon Fuels
  • Chlorinated compounds

Air sparging is an in-situ remedial technology used to reduce the concentration of VOCs in groundwater. Contaminant removal occurs in three separate processes in an air sparge system:

  • Phase transfer from dissolved to vapour phase (occurring in the saturated zone)
  • Phase transfer from absorbed to vapour phase (occurring in the capillary fringe and unsaturated zone)
  • Aerobic biodegradation of the contaminant in both the saturated and unsaturated zones

These processes are facilitated by the injection of air into the subsurface saturated zone. The injection induces a phase transfer (evaporation) of the VOC’s from the dissolved and sorbed state to the vapour phase. This increased oxygen into the subsurface stimulates the natural microbes, thereby increasing the biological degradation of the contaminants.

Air Sparging is effective in the reduction of VOC concentrations at petroleum hydrocarbon impacted sites. Nichols Environmental has installed and maintained a number of air sparging systems with great success. We are responsible for the proper installation of the injection wells, pumps, and piping required to inject the suitable amount of compressed air into the contaminated zone.

Dual Phase Vacuum Extraction (DPVE)

Relevant Contaminants (Volatile Organic Compounds (VOCs):

  • BTEX Components
  • Hydrocarbon Fuels
  • Solvents

Dual Phase Vacuum Extraction (DPVE) is an in-situ remedial technology used to reduce the concentration of VOC's in the groundwater and soil mass.

  • Utilizing a high negative pressure (vacuum), the system simultaneously removes contaminants from three different sources:
  • Volatilized contaminants in the unsaturated zone
  • Free Product contaminants perched on the water table [Light Non Aqueous Phase Liquids (LNAPL)
  • Contaminants dissolved in the groundwater

The vacuum extraction well is screened in the zone of the contaminated soils and groundwater. Contaminant removal occurs from above, below, and throughout the groundwater table. As contaminated groundwater and free product is removed, the water table drops, exposing more of the contaminated soils now in the unsaturated zone. Once the liquid and vapour phase contaminants are drawn above ground, the phases can be separated and treated accordingly using various technologies.

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DPVE has shown to be effective in the reduction of VOC's and hydrocarbon fuel concentrations at petroleum hydrocarbon impacted sites. Nichols Environmental's role in a DPVE System includes the installation, supervision, and monitoring of extraction wells, piping, and the treatment system.

We have successfully installed and maintained a number of DPVE systems with great success.

Chemical Injection / Oxidation Programs

Oxidation / Reduction / pH Stabilization / Nutrients / Biologicals

Relevant Soil and Groundwater Contaminants Include:

  • Petroleum Hydrocarbons
  • Polycyclic Aromatice Hydrocarbons (PAHs)
  • Solvents
  • Heavy Metals
  • pH altering chemicals

Chemical injection is a remedial technology that Nichols Environmental has developed and used since the company's inception. The istar™ technology (in-situ treatment and remediation) is a patent pending delivery system for injecting various inoculants into the soil and groundwater at varying depths. Inoculants include oxidants, reducing agents, pH adjusters, oxygen/air, water, nutrients, and biological organisms.

Nichols Environmental has treated contaminated sites across Canada using this process, with the largest in-situ chemical oxidation program being completed in Alberta, covering an area of 7,000 m2 to depths of greater than 10 metres.

The technology can be used to remediate contamination below a concrete slab, around a tank farm, or beneath a rail line without demolition – meaning minimal disruption to our client's daily operations.

Alternative Remediation Solutions

istar™ can be used as a stand alone treatment system, or to augment other remediation programs such as vapour extraction, dual phase vacuum extraction, bio-venting, pump and treat, and/or bio-piles. The technology provides an alternative for areas with complex, inaccessible, or expensive contaminant problems by eliminating costs associated with excavating, hauling and landfilling or extended pump and treat programs. The istar™ treatment unit is a self-contained, trailer mounted, mobile unit consisting of pumps, compressors and stainless steel injection lances.

Excavation and Disposal

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Relevant Contaminants: All Soil Bound Contaminants

Remedial Objective: Removal

Excavation of contaminated soil is a remedial process designed to physically remove the contaminant source and source materials from the subsurface.

Nichols Environmental has been involved with numerous excavations, and have shown success in the remediation of all sites.

Using construction equipment such as a backhoe, the contaminated material is removed from the ground such that it can be treated or disposed of at a licensed landfill. Depending on the nature of the contaminant, the material removed can be treated on site and replaced, treated off site and used as fill elsewhere, or disposed of at a landfill which can specifically handle the contaminant in question.

Although considered a basic remediation tool, Nichols Environmental has shown that the excavation of contaminated material is an efficient and cost-effective method for the clean up of a contaminated site. Our role in such a project entails the tendering, contract award, direction, and supervision of construction crews for the removal of the contaminated soil such that the material which remains, meets, or exceeds local guidelines and regulations.

Landfarming

Site location, end use location, and landfarm site availability govern where excavated impacted soil can be treated and used. Three options are available:

  • treated and replaced on site
  • treated and used as fill elsewhere
  • disposal of at a regulated landfill

Landfarming is a cost-effective and simple method for the remediation of VOC-impacted soils. By tilling and aerating the impacted soils, VOC’s are evaporated out of the soil mass until contaminant levels are below applicable guidelines.

Nichols Environmental is responsible for the geological characterization of the proposed site, preparation of regulatory approvals and permits, and supervision of site preparation including scarifying and compacting of the clay subgrade. Confirmation soil sampling of the treated soil and the original clay base is performed by Nichols Environmental to complete the remediation program and regulatory reporting requirement.

Nichols Environmental has completed numerous landfarming remediation programs for VOC-impacted sites. All soil excavated has been treated to a level which meets or exceeds the applicable guideline for each site.

We are one of the few consultants using landfarming as the primary means of ex-situ remediation. Alberta Environment Northern Region has commented that no other consultant permits as many landfarms as Nichols Environmental. In fact, we landfarm and successfully remediate approximately 100 m3 of soil for every 1 m3 that is hauled to a landfill.

We have extensive experience in dealing with Alberta Environment and have been approved to construct and operate landfarms in sensitive ecological, and urban areas.

Bio-Remediation

Relevant Soil Contaminants: All Biodegradeable Contaminants

Remedial Objective: Conversion and/or Destruction

Bio-Remediation is an in-situ or ex-situ remedial technology in which enhancements to the natural processes of the environment speed the degradation of contaminants. These processes are able to convert or destroy harmful chemicals into harmless ones such as water and carbon dioxide.

Natural microbes which reside in the soil and groundwater are often able to degrade certain harmful contaminants through digestive processes. In order for microbes to efficiently and completely degrade contaminants, proper conditions in the subsurface are required. In situations where natural conditions are not ideal, enhancements can be made. The following enhancements are most common:

  • Addition of oxygen via pumped air or oxygen release compounds
  • Addition of nutrients for proper microbial digestive processes
  • Adjustment of temperature
  • Adjustment of soil or groundwater pH and,
  • Addition of specific microbes better suited to digest contaminants

When enhancements to the contaminated area are not viable in-situ , contaminated water and soil can be removed and treated ex-situ . In such cases, control of the environmental conditions is greater, therefore allowing for more efficient degradation.

Nichols Environmental’s in-situ Treatment And Remediation (istar™) Technology is a patented delivery system allowing for the injection of the above inoculants in situations where complex, inaccessible, or expensive contaminant problems are found. In Bio-Remediation projects Nichols Environmental is responsible for injection of proper inoculants into the contaminated soils and groundwater.

Nichols Environmental has been involved with many projects utilizing Bio-Remediation.

Locations

Head Office – Edmonton
17331 – 107th Avenue NW
Edmonton, Alberta T5S 1E5

Phone: (780) 484-3377
Fax: (780) 484-5093

Calgary Office
427 Manitou Road SE
Calgary, Alberta T2G 4C2

Phone: (403) 452-1820
Fax: (403) 984-8803

What's New

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    From one of our clients: "Folks at Nichols - I have a few things to say: One is thank you; and YOU GUYS ROCK !! So glad to have you on our team!  We call with emergency and wit...
  • February 28, 2017
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