I didn't know that!
Zinc, (or aluminum)... which is what they're made of... don't handle alkalai very well. They quickly degrade to little more than white dust. I am surprised they're actually sold in concrete- an alkalai.
The one in the pics was certainly in poor shape. Every such box I have seen, either buried in concrete, or just buried in dirt,
has been seriously corroded, and filled with mud. This is true even when the cover appears to have a gasket, and be properly installed.
I replaced this arrangement with a handhole, and traffic-rated cover.
