30 CFR §550.1154

1. (a)You must determine whether each reservoir is sensitive. You must classify the reservoir as sensitive if:
   1. (1)Under initial conditions it is an oil reservoir with an associated gas cap;
   2. (2)At any time there are near-critical fluids; or
   3. (3)The reservoir is undergoing enhanced recovery.
2. (b)For the purposes of this subpart, near-critical fluids are:
   1. (1)Those fluids that occur in high temperature, high-pressure reservoirs where it is not possible to define the liquid-gas contact; or
   2. (2)Fluids in reservoirs that are near bubble point or dew point conditions.
3. (c)The Regional Supervisor may reclassify a reservoir when available information warrants reclassification.
4. (d)If available information indicates that a reservoir previously classified as non-sensitive is now sensitive, you must submit a request to the Regional Supervisor to reclassify the reservoir. You must include supporting information, as listed in the table in § 550.1167, with your request.
5. (e)If information indicates that a reservoir previously classified as sensitive is now non-sensitive, you may submit a request to the Regional Supervisor to reclassify the reservoir. You must include supporting information, as listed in the table in § 550.1167, with your request.