If the Department of Energy holds to a date released in February, this Thursday would mark a major milestone toward the resumption of transuranic waste storage at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, N.M.

Thursday is the date — according to the the 12-month WIPP Integrated Baseline developed by DOE and WIPP prime Nuclear Waste Partnership — on which contractor personnel were slated to finish their operational readiness review: a milestone in which Nuclear Waste Partnership would inform DOE it is ready to resume operations of the nation’s only disposal facility for the radio-contaminated material and equipment known as transuranic waste. The facility has been closed since two accidents in February 2014.

The contractor readiness review was supposed to start June 16, according to the public schedule in the WIPP Integrated Baseline; it is not clear it did. It took two months longer than expected to approve a critical safety document that was a major bottleneck for the remaining WIPP restart activities, but DOE and its contractors maintain waste emplacement will resume on Dec. 12, or sooner.

That is despite the fact that the rightward slip of that critical document — the documented safety analysis (DSA) — precipitated delays for another crucial WIPP restart activity, integrated cold runs: an eight-week program of waste-emplacement dress rehearsals in which Nuclear Waste Partnership practices the tighter new disposal procedures in the DSA using waste containers packed with non-nuclear materials. They were intended to begin on Feb. 22 and be completed on May 5.

Assuming DOE and its contractor work the equivalent of seven days a week at the site, integrated cold runs that began June 1 and lasted eight weeks would wrap up July 27. During a June 1 WIPP town hall meeting webcast from Carlsbad, Jim Blankenhorn, Nuclear Waste Partnership’s WIPP recovery manager, said the contractor readiness review would not begin until after integrated cold runs ended.

The WIPP Integrated Baseline includes 72 days, counting weekends and holidays, of what DOE and its contractor call “schedule uncertainty buffer.” Again counting weekends and holidays, the documented safety analysis — which was approved May 29 — was delivered 100 days after the deadline in the WIPP Integrated Baseline.

A Nuclear Waste Partnership spokesperson did not reply to a request for comment Monday. Representatives for the contractor and DOE’s Carlsbad Field Office have refused multiple requests dating to June 20 to explain in detail the amount of wiggle room they built into the 12-month WIPP Integrated Baseline.