Section 250.1204 - Surface commingling(a)What are the requirements for the surface commingling of production? You must:(1) Submit a written application to, and obtain approval from, the Regional Supervisor before commencing the commingling of production or making any changes to the previously approved commingling procedures. Your application (which may also include any relevant liquid hydrocarbon and gas measurement requests) must be accompanied by payment of the service fee listed in § 250.125 . The service fees are divided into two levels based on complexity, see table in § 250.1202(a)(1) .(2) Upon the request of the Regional Supervisor, lessees who deliver State lease production into a Federal commingling system must provide volumetric or fractional analysis data on the State lease production through the designated system operator.(b)What are the requirements for a periodic well test used for allocation? You must:(1) Conduct a well test at least once every 60 days unless the Regional Supervisor approves a different frequency. When a force majeure event precludes the required well test within the prescribed 60 day period (or other frequency approved by the Regional Supervisor), wells must be tested within 15 days after being returned to production. Thereafter, well tests must be conducted at least once every 60 days (or other frequency approved by the Regional Supervisor);(2) Follow the well test procedures in 30 CFR part 250 , subpart K; and(3) Retain the well test data at the field location for 2 years.