The federal General Services Administration---the agency that oversees federal buildings like the Federal Office Building in downtown Seattle---has made it clear to the Washington State Department of Transportation that the deep-bore tunnel can't go under the building, where WSDOT plans to build it, until the state agency resolves a number of major issues.

The state has to get permission from the federal government to bore its tunnel beneath the federal building.

In a series of increasingly terse letters beginning last April, GSA officials have made it clear to WSDOT that the federal agency won't allow the tunnel to go beneath its building until the state addresses serious concerns about the tunnel, which would run directly beneath or in the middle of the piers holding up the building, putting "this historic building and its occupants in permanent jeopardy," according to the GSA's most recent letter, dated December 13.

A tunnel underneath the building, the December letter continues, would make it impossible for the government to replace the timber piles holding up the building in the future, and could make building renovations impossible.

Additionally, the land under the building is expected to settle during and after construction, potentially damaging the fragile historic structure. "A historic masonry structure like the Federal Office Building could experience cracking of brittle finishes and even cracking through the mortar joints due [to] this settlement."

Finally, the letter notes that methane has built up beneath the building as organic material piled up to create land for building construction in the early 1900s has decayed. "What is the proposed method for monitoring and mitigating any methane gas build-up within the tunnel and specifically around the Federal Office Building?"

The GSA raised many of the same concerns back in April, when acting regional GSA administrator Robin Graf expressed hope that WSDOT and the feds could clear up the GSA's questions at a meeting later that month. Clearly, that didn't happen, and in a subsequent letter in November, Graf noted that the GSA has not given WSDOT the right to drill its tunnel under the building, and that "consequently, we will not be granting any further access to the federal property by the project team, their contractors, or potential bidders."

We'll have an update tomorrow when WSDOT and GSA officials are back in their offices after the MLK holiday.