equipment, liner tops, and wellhead seals) should be verified by using the best available test procedures. All tests should have established procedures and predefined criteria for acceptable performance and should be subject to independent, near-real-time review by a competent authority.

This includes the timing of the start and the magnitude of the pressure tests compared with the amount of time needed for strength development of the cement, the results of the pressure tests, verification that the flapper valves have closed and the other mechanical seals are holding, and evaluation of cement bond logs.

Well Design Review

Recommendation 2.4: The general well design should include the review of fitness of components for the intended use and be made a part of the well approval process.

For example, the review should consider alternatives to the use of a series of two cement slurries that will be gravitationally unstable during placement in the well and potentially result in a slurry that does not achieve the desired compressive strength. The review should also consider the use of a differential fill device because the use of this device in the Macondo well appears to have contributed to the failure of the flapper valves to perform their intended function.

Well Construction Practice

Recommendation 2.5: Generally accepted good operational or best practices should be used in the construction of the well. Such practices would ensure that the most accurate well data are passed from the operator to the various contractors for use in simulations and design and that the results are considered by all parties before implementation.

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