What's with this pipe?

[sylvar]

What's with this pipe?

Does anyone know why this pipe has its own bridge? What does it probably carry?

Comments

[sylvar.livejournal.com]

What gives you that idea? Did I miss a hazmat-1971 sign?

(I don't doubt that it's a reasonable guess, but I'm interested in how you reached it.)

[sylvar.livejournal.com]

Oh, I see cbustapeck deleted his post to which I was replying...

[cbustapeck.livejournal.com]

There were some pictures of CNG pipelines going into and out of Manhattan posted a while ago on cryptome.org. These appeared to be then same. Then I tried to find the photographs, and have not been able to, which is why I deleted my comment, because I'm not feeling so sure.