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Are mobile boosters eligible for the transportation exemption?

An oil company owns many wells on an oil field.  Each well is on its own plot of land.  These plots are not adjacent or contiguous and, therefore, each well is its own facility.  When operating these wells, it is sometimes necessary to inject air or gas into the well to get the flow of oil started.  The machines that inject the gas are called boosters.  The booster is a portable piece of equipment that can be attached via a hose to more than one well at a time.  Once the wells are flowing, the booster can be moved to another location on the oil field to boost other wells.  The booster contains some extremely hazardous substances (EHSs) that are released during normal operations.  The amounts of some EHSs exceed their threshold planning quantity.  Since these boosters are mobile and never part of a well (not part of an existing facility), can they be exempted under the transportation exemption?

The transportation exemption applies to EHSs that are traveling in commerce, such as in a truck, or are in transit, such as in a pipeline.  Therefore, when the boosters are being moved and are not attached to any facility, they are in transit and exempt under the transportation exemption (except for Section 304).  However, when the booster is stationary and/or attached to the wells, it is not in transit or traveling in commerce and must be reported.  Even though it is a temporary site, the presence of those EHSs above the threshold planning quantities (TPQs) is of concern to the local planning emergency committee (LEPC). Therefore, the EHSs in the booster should be reported under Section 302 in the same manner as a chemical that is only on-site for part of the year, which includes the time at one location. Similarly, any EHS present in the hose that is attached to the well from the booster is considered process equipment and subject to reporting as part of the booster.  A generic report may be prepared (i.e., one Tier I/II for similar wells).  Therefore, one set of Material Safety Data Sheets (MSDSs) and one Tier I/II may be prepared for similar boosters with the same EHSs in similar amounts and submitted to each State emergency response commission (SERC), LEPC and fire department under whose jurisdiction the oil field falls.