Who was responsible for the Big Dig Tunnel collapse?

Cross-posted from the Accountable Strategies blog

One is tempted to ask whether she will be satisfied at that point.  But if she gets one conviction or 10 convictions,  will that make our highway and tunnel system safer?  Will those truly reponsible for the accident have been held accountable?

I wish Coakley would take the time to read What Sank the Thresher?, a revealing article about who was responsible for the sinking of a nuclear-powered submarine off the coast of Cape Cod with the resulting loss of 129 men April 1963.  It was the worst submarine disaster in U.S. history; and while we’re talking about subs here and not tunnels, there are a number of telling parallels with the Big Dig catastrophe.  I wish the editors at The Globe and in other media outlets would read this article as well.

The Thresher sank during a test dive after a pipe burst in the hull of the vessel, setting off a chain of events that sent the sub plunging to ocean depths that collapsed and split apart the hull.

Interestingly, the court of inquiry in the Thresher case did not recommend disciplinary action for any of the parties involved, and apparently the case resulted only in the loss of a promotion for one Naval officer, the skipper of the Thresher’s escort vessel on the day it sank.  Yet, in the wake of reforms adopted in Naval operations and procedures following the sinking, the safety of our submarine fleet was significantly and dramatically improved.

Although the exact cause of the sinking of the Thresher has never been conclusively determined, the resulting investigations found, according to the article, that there was (and I’ll admit this isn’t as sexy as alleging criminal behavior by individual parties):

…a catestrophic failure in the Navy’s basic approach to design, development, and testing.  They (the investigations) pointed up a critical need for the creation and implementation of engineering standards that would be strictly observed, especially in the design and construction of complex and technologically sophisticated systems.

Compare this with the basic findings of the National Transportation Safety Board in July, following its year-long investigation of the Big-Dig tunnel collapse.  The four basic “safety issues” that the NTSB identified during its investiation were (and these drew barely a mention in the news articles covering the release of the report):

–Insufficient understanding among designers and builders of the nature of adhesive anchoring sytems (for the tunnel ceiling panels);

–Lack of standards for the testing of adhesive anchors in sustained tensile-load applications (heavy loads over time);

–Inadequate regulatory requirements for tunnel inspections; and

–Lack of national standards for the design of tunnel finishes

In both cases, investigators pointed to design and testing problems and a lack of industry standards for the manufacture of the submarine and tunnel systems respectively.

This isn’t to say that human error and negligence, even criminal culpability, weren’t involved in either case.  They were.  Companies were eager to make a profit in both cases, and both Navy and CA/T officials were subject to budgetary and political pressures in completing their respective projects.

In the case of the Thresher, there was political pressure to deploy new weapons systems quickly and inexpensively in reponse to the Soviet threat, leading to the relaxation of standards in the rush to launch the submarine.

The NTSB hints at the existence of bugetary pressures in describing the decision to install precast concrete panels in the I-90 Connector Tunnel in Boston, which were cheaper and less time-consuming to install than the custom-engineered, lightweight concrete panels that had been installed previously in the Ted Williams Tunnel.  Yet, like the Ted Williams Tunnel, the I-90 Tunnel had no embedded ceiling supports, leading to the decision to use adhesive anchors to hold the ceiling panels.  The adhesive or epoxy is, of course, what gave way, causing the ceiling collapse.

In both the Thresher and the I-90 Tunnel, testing prior to completion or commissioning revealed the potential for catastrophic problems with key equipment.  During the final overhaul of the Thresher at the Portsmouth Naval Shipyard about a year before the sub sank, 14 percent of the sub’s soldered pipe joints failed ultrasonic tests.  Despite these results, Portsmouth “did not aggressively pursue the ultrasonic inspection of … (pipe) joints in Thresher,” the article quotes the court of inquiry as determining, even though the rejection rate “was a clear indicator that additional action was required.”

Similarly, the NTSB report noted that in September 1999, four years prior to the opening of the I-90 Tunnel, a Modern Continental employee noticed that several of the anchors in the tunnel ceiling had begun to pull out.  Yet, neither Modern Continental nor Bechtel/Parsons Brinckerhoff, the engineering consortium that designed and managed the Big Dig, continued to monitor the performance of the anchors or to determine the cause of the problem.

In both cases, investigators found plenty of blame to go around.  Powers Fasteners came under withering criticism in the NTSB report for failing to identify the source of the failure of its product in the tunnel ceiling in 1999.  The report states that at least some officials within the company were aware that Powers’ fast-set epoxy was subject to long-term load failure or “creep,” but this information was apparently not passed on to Powers engineers who examined the failed anchors in the tunnel.

Compare this once again to the inquiry into the Thresher, in which the court found that serious failures of similar pipe joints had been found in five other submarines prior to the launching of the Thresher, yet that information wasn’t shared or acted upon.

There are numerous other parallels between the two cases, involving a lack of testing requirements and a failure to follow existing standards in both instances.  In both cases, investigators made many recommendations to beef up testing, standards, and procedures.  In the 44 years since the Thresher’s sinking, the Navy has lost only one other submarine–the Scorpion, which sank at sea in 1968.

At a Congressional hearing into the Thresher case, Adm. Hyman G. Rickover, the father of the nuclear Navy, was asked how it was possible that no one could be held at fault for the Thresher’s sinking.  Rickover’s answer was:

Who is responsible?  With the present Navy system, this is an almost impossible question to answer.  The nearest you can come is to say that ‘the Navy is responsible.’  In other words, all you can do is point to a collectivity.