Arch Might Look Shabby, But It's Not Going to Fall On You
|Arch might not have been properly cleaned post-erection.|
Goodie!.....But what's causing the stains?
A Chicago-based engineering firm has determined in a report issued on September 7 that the culprit is likely the welds holding the Arch pieces together.
It appears that either atmospheric pollutants are reacting to the welds, or there was "inadequate cleaning and polishing of the Arch after erection."
If we've learned nothing else, it's that you must always clean and polish after erection.
Read the NPS statement on the report here.