Alaska Soil Recycling (ASR), a division of Anchorage Sand & Gravel, Co., Inc., pioneered the first thermal remediation service in Alaska. ASR provides services to a diverse group of clients, including oil and gas, construction, municipal, state and federal agencies, military, financial institutions, and the private sector. Our facility has treated more petroleum-contaminated soil than any other within the state of Alaska.
ASR provides the only fully bonded facility recognized by the Alaska Department of Environmental Conservation in the state of Alaska.
Setting Industry Standards
ASR has participated as an advocate of the private sector with the State and as the regulations have developed. As a result, our model and standards have become most favored by the Alaska Department of Environmental Conservation (ADEC) while maintaining an unmatched compliance record.
Other value-added qualities that set our process apart are:
- Engineered and State certified stockpiling pad
- Monitoring and security
- In-house laboratory sieve analysis
- Post-treatment remediation results reported by a qualified impartial third party
- Recycling and reuse for remediated soils
- Preprocessing capabilities to segregate deleterious materials from impacted soil before treatment.
ASR’s policy is to treat soils to the ADEC’s most restrictive levels, effectively allowing unrestricted reuse. The remediated soils are made available to the construction industry, individuals, non-profit organizations, charities, and businesses; therefore, avoiding the consumption of valuable landfill space.
Soil acceptance criteria at our facility is based on the Alaska Administrative Code (AAC) and individual Alaska Department of Environmental Conservation (ADEC) guidance documents.
The guidelines below are not considered comprehensive, but they cover the majority of the ADEC programs for handling contaminated soil in a way to be protective to human health, safety, and welfare of the environment.
Soil Acceptance Guidelines
- Title 18 AAC Chapter 75 – Oil and Other Hazardous Substances Pollution Control
- Title 18 AAC Chapter 78 – Underground Storage Tanks
- ADEC, division of Spill Prevention and Response – Soil Treatment Facility Guidance
- ADEC, division of Spill Prevention and Response – Site Characterization Work Plan and Reporting Guidance
Permits to operate a soil treatment facility are provided and enforced by the ADEC. Additionally, the ADEC has a well-developed program that regulates the responsibilities an owner may have when contaminated soils are generated. Required permits and certifications to operate a treatment facility in Alaska include:
- State approved Facility Operations Plan – ADEC, Contaminated Sites Program
- EPA Air Quality Control Permit – ADEC, division of Air Quality
- Certification of fiscal responsibility/bonding – ADEC, Contaminated Sites Program
Thermal desorption cleans the soils while eliminating hydrocarbon contamination under all conditions in a timely manner. The process will clean soils to meet or exceed the most restrictive regulatory guidelines.
Some typical contaminates that are routinely encountered include the following:
- Aviation gas
- Natural gas condensate
- Hydraulic oil and gear oil
- Used oil
After excavation, the contaminated soil is placed in a hopper and fed to a rotary dryer unit. There, it is heated to temperatures that sufficiently volatize the petroleum hydrocarbons. The exhaust gases from the dryer system are then carried through a dust collection system called a “baghouse.” Only the gases are subsequently carried to the thermal oxidizer unit.
In order to ensure total oxidation of the contaminants in the thermal oxidizer, instrumentation measures the levels of oxygen, temperature, and any carbon monoxide in the outlet gas stream. Sampling and analyses of the clean soils exiting the system are conducted to verify soil remediation prior to recycling.
Why Thermal Desorption?
Thermal desorption effectively eliminates petroleum contamination in a timely manner while other technologies do not. This is evident in Alaska where natural environmental conditions suppress the success rate of most other technologies. During Alaska’s reduced heating degree days, permafrost, arctic conditions, intense moisture, and shorted field seasons, we believe that thermal desorption is the only guaranteed approach.
The recycling and reuse of soil after thermal desorption prevents the consumption of valuable landfill space. Although landfilling is a legal option, many companies discourage the use of landfills in their environmental stewardship policies whenever possible. Furthermore, the use of clean burning natural gas and the prevention of non-combusted volatile gases exiting the system appeal to the Green and Sustainable Remediation (GSR) practices that are encouraged by our customers.