Wednesday, March 16, 2011

Japan Quake: Some Forward Looking Points

1) That Incident Report for the Fukushima reactor complex gets more potentially revealing with every day that passes. I suspect it will include extensive use of equivalent phrases to "Cognitive Lock", "Following Procedure", "Blind Spots", and "Fresh Eyes" as what, in any other situation, would be called a comedy of errors continues to pile up. How, exactly, does one lose coolant flow to the storage pools and then not remain aware of the situation to the point that the water is boiling off, the stored fuel is increasingly exposed, and the temperature is rising until the heat building up in the room sets the storage facility on fire?

Quite simply, it happens when you're so focused and confused by what's happening over here that the things going on over there just don't look that important and this blind spot in your troubleshooting becomes potentially devastating. This was essentially what happened at Three Mile Island: the operating team got more and more focused on and confounded by the reality that the reactor, and its coolant level, kept behaving in ways contrary to their efforts and what the instruments were telling them that they never noticed some odd behaviour coming from a Pilot Operated Release Valve (PORV) and it's subsystems; a safety device designed to reduce steam pressure in the loop that was stuck open and thwarting their every effort. It was only hours into the event, when the next crew showed up, that one of the engineers on that team began looking at the problem with a clean slate, noticed that the readings on the outlet pipe for the PORV in question were suspiciously hot for a valve that was supposed to be closed, and triggered the hard lockdown on the outlet: finally stopping the outflow of steam that had prior crew piloting the reactor in a death spiral and, ultimately, preventing the outright meltdown the station was on course for.

There's a lot of press right now about how the Fukushima crew are "Heroes" for staying on as things have continued to go to hell there and the radiation levels have reached dangerous levels and, to that extent, it's inarguable that they are. But, the reality is that they should have been cycled out a long time ago, "face" and "duty" be damned. We're now five days in and they need sleep and time to de-stress because running on adrenaline, fear of explosion (from the hydrogen), and cognitive lock from the reactor behaving in ways unexpected and gauges telling you things that seem incomprehensible leads to bad decision making and compound mistakes regardless of how capable the crew otherwise might be. The plants need a fresh set of eyes on site, not on phone, to start attacking what's going on there - perhaps from multiple angles and multiple crews to individually tackle the coolant pools and reactors because there's quite obviously not enough people at hand to manage the overall situation as is. There are 55 nuclear plants in Japan, many of which are of similar design, it's time to start drawing up a list of who's the "best available" and prepare swap crews.

That said, just to be perfectly clear, I'm not challenging the competence or bravery of these people, just the reality that human beings can get locked up in mental blocks if they focus on a problem too long. Hell, I've done it while programming: sat there staring at the screen trying to figure out why my code isn't doing what I'm telling it to... then stepping away, coming back to it and.... fuck I've closed this loop here by dropping an endline ; out of habit. Imagine having to troubleshoot like that for days with a complex machine where your only means of feedback are dials and gages you're trusting to give you the right answers, the consequences of miss-reading or them being wrong can be fatal, and there's a national tragedy going on all around you that may directly affect you as well. I'm not a big fan of psychology, but I suspect a majority of head-doctors would say it's inarguable that these people could and should have had relief by now unless they have and we've just not heard about it.

2) Rebuilding of the Tsunami afflicted areas poses some interesting questions because, while there will likely be some migration out of the effected areas, the overwhelming human mentality is to stay where "home" is. How best to enable that will likely be a lively debate because, given the total devastation in some areas, there's more than one way to potentially skin that fish.

You could double down and rebuild on site. This is the point in the movie where the Mayor delivers the arousing speech about how: "We'll rise again stronger!", and, really, this is frequently the most compelling option. There's a certain human tenacity (see also: New Orleans, Hudson's Bay Native Canadians living on flood planes), that favours the familiar and traditional attachments over change. The problem with this is that nature has a habit of kicking our ass when it wants to despite our best efforts to engineer around it. Japan built a large variety of Seawalls explicitly to try and prevent events like last Friday (also: to line the pockets of companies favourable to the government of the day/"stimulus"). Last week, they got crushed in pretty much every case.

You could argue that the solution to this is bigger seawalls but... waves in places of absolute destruction like Minamisanriku, where the structure of the bay served to channel the force of the Tsumani into a cascading wall of death, hit 60'(~18m) high. The second problem with seawalls is that, as studies of the 2004 Tsunami found, they're less effective than natural trees with deep roots that absorb and give with the impact to dampen energy. Unlike that situation, a seawall functions like clamping your fist on the drive shaft of an electric motor: if you're lucky, it might burn out but, more likely, it's just going to build energy until it overwhelms the obstacle and moves on. Such man made defences are also hugely expensive to build and maintain. There's an argument to be made that they're effective stalls to provide more time to evacuate... but the money may better be spent on better evacuation equipment and/or shelters.

Creating a community on stilts so that homes could remain above the force of the wave is another option but the key question will be: how do we do that, while accepting the reality of three story waves and still remaining earthquake proof? It's not an impossible conflict of features to overcome, but it's cognitively a hard sell (wait, you want me to build my house 20m off the ground???), and may simply not be cost or space effective as well.

The least popular, though probably most effective method in those areas where there's literally little of anything to return too, would be simply to move the residential areas of these cities and villages inland/onto higher ground and provide effective transit (that could double as evacuation vehicles), to the waterfront. Effort could then focus on reclaiming as much of the former cityscape as possible for other uses to compensate for the lost land elsewhere and strengthening safety features around those facilities that need to be exposed to the waterfront.

The problem with that is that it means walking away from history and physical attachment. Mankind as a whole has never been good at that, given any other option, so it will be interesting to see which, if any, communities choose to attack their rebuilding program from this angle.

Whatever they choose, parts of North-Eastern Japan are likely going to look substantially different in 5-10 years from now than it did on March 11th.

Edit: This video

shows the third problem with seawalls: they provide false security. In the town/area of Kamaishi, residents tell of those who stayed behind them with the expectation they'd be safe because the walls worked for smaller events before. This... did not end happily this time.

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