Residential Underground Ground Heating Oil Tanks were historically installed after World War 2, up to 1980. The oil crisis of 1973, resulted in many conversions to other energy sources, most commonly natural gas. After personally ecommissioning around 3500 underground heating oil tanks, inspections reveal many heating oil tanks were abandoned. We specialize in decommissioning, there are two methods of decommissioning, removed or filled in-place with gravel or sand. Filling with water is not an approved method of decommissioning.

With over 25 years of residential tank cleanup experience, Spartan Environmental can guide you through the DEQ closure process and make sure that the project is successful. Spartan heating oil tank cleanup projects always start with an assessment. First part of the site assessment is to complete a scan of the property, using a deep scan metal detector we will identify if there is a tank on the property. Then determine the size, depth of the tank, and the tank contents.

After a tank is located, we collect additional soil samples and investigate site-specific conditions such as levels of diesel in the soil. If the tank is leaking then we determine the volume of the contaminated soil, vertical depth of the contaminated soil, and the depth to groundwater in the area. The process finishes with complete a full report to document the project and submit it to the DEQ for review and file closure.

Sometimes the level of contamination in the soil is simply too high to leave in the ground. In these circumstances the highly contaminated soil needs to be excavated. The process of cleanup, we first remove the tank. If the tank is in an area where we can use our small rubber track excavator, we would excavate the contaminated soil, and transport the petroleum impacted soil for offsite disposal at a landfill. Alternately in limited access areas we can use vacuum truck to complete the excavation cleanup. With the completion of the excavation, we sample the excavation area to confirm all the contamination has been removed or to determine what levels are still remaining. If lab analysis determines there is still contamination remaining but at significantly lower levels, then we may conduct a risk assessment and attempt to close the site using the risk-based closure process.

Risk assessment would involve completing perimeter borings. Spartan Environmental completes perimeter boring with either hand augers, hand advanced geoprobe large bore core sampler, or with a small tracked AMS Drilling Rig, with core sampling. If lab analysis confirms all the contaminated soil has been removed and or the perimeter assessment delineated the remaining impacted soil. The tank excavation can be backfilled, restore the site work area, and submit a cleanup report to the DEQ.

Heating oil tank projects in Oregon are common, and considered a resolvable environmental problem, with experienced environmental remediation firm, Spartan Environmental.

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Above ground tank cleanup
Underground heating oil tank uncovered for decommissioning by removal.
Heating oil tank excavation cleanup
Heating oil tank excavation after removing a leaking heating oil tank
Heating oil tank cleanup with excavator
Heating oil tank manhole, cleaned and ready for gravel fill
Heating oil tank interior cleaned with dry absorbent
Soil Samples with hand auger
Soil Sampling Geoprobe Hand advanced core sampler
Heating Oil Tank Decommissioning in-place with peagravel
Heating oil tank that was abandoned, every abandon tank contains sludge residue
Heating oil tank decommissioning with tank under the deck
Heating oil tank filled in-place with perlite slurry
Heating Oil Tank removed from the ground