TANK DECOMMISSION & CLEAN-UP SERVICES
 

The lab results of two site assessment soil samples determine, what kind, and, how much, of an environmental clean-up is required.  There are six basic clean-up categories, depending on the severity of contamination:
  1)  Clean Decommission (0-49 ppm diesel)
  2)  Soil Matrix Level 1 (50-499 ppm diesel)
  3)  Generic Remedy Level 1 (500-2,499 ppm diesel)
  4)  Generic Remedy Level II (2,500-2,499 ppm diesel)
  5)  Risk Based Corrective Action in-place (10,000+ ppm diesel)
  6)  Risk Based Corrective Action tank/soil removal (10,000+ ppm diesel)

1)  CLEAN DECOMMISSION - When a tank has not leaked or has leaked only a trace amount (<50ppm), it can be decommissioned in the ground (in-place) with no further sampling.  Please note that if your tank has leaked a trace amount, it is highly recommended that it be decommissioned.  Trace amounts of oil indicate that the tank has just begun to leak and will only become a bigger and more expensive problem in the future.

2)  SOIL MATRIX - If soil ample lab results indicate that the contamination level in the soil is between 50-499 parts per million of diesel, then the action required is called a Soil Matrix clean-up.  The tank can be decommissioned in place with no further sampling.

3) GENERIC REMEDY LEVEL 1 - If soil sample lab results indicate that the contamination level in the soil is between 500-2,499 ppm diesel, then the tank can be decommissioned in-place, however, additional sampling is required.  Four or five additional samples around the tank are required to delineate the underground distribution of contamination.

4) GENERIC REMEDY LEVEL 2 - If soil sample lab results indicate that the contamination level in the soil is between 2,500 - 9,999 ppm diesel, then the tank might be able to be decommissioned in-place, but it could also potentially require removal.  Additional samples are required and additional lab analysis must be performed on the soil samples that test for Benzene, Toluene, Ethylene, and Xylenes (BTEX).  If the concentrations of these hydrocarbons are higher than allowable levels, then the site jumps to the next level of clean-up requirements.  The Risk Based Corrective Action (RBCA) (see next category).

5)  RISK BASED CORRECTIVE ACTION (RBCA) - If soil sample lab results indicate that the contamination level in the soil is 10,000 ppm or greater, then further lab analysis is required.  A BTEX-PAH analysis must be performed on the site assessment soil samples to determine the concentrations of a group of regulated hydrocarbon contaminants.  (Benzene, Toluene, Ethylene, Xylenes, and Polynucleic Aromatic Hydrocarbons).  The BTEX-PAH analyses must be performed within 14 days of the soil sample extraction date.  If it is determined that the concentrations of contaminants is within allowable levels, then the tank may be decommissioned in-place with additional sampling.  If the contaminant levels are too high, then tank and soil removal may be required.

6)  RBCA TANK AND SOIL REMOVAL - If the BTEX-PAH analysis shows petroleum contamination is at concentration levels that are a threat to human health, then the tank, and as much contaminated soil as possible, must be removed to avoid human exposure to hazardous chemicals.  An excavator is used whenever possible;  however, tanks and soil must sometimes be removed by hand.