One Possible Source of This "Liquid "Non-Hazardous Substance"

Human waste spill reported on I-94 eastbound near Racine   (Milwaukee Journal Sentinel, 8/17/2014)

Honey, why does the garage smell like shit?  The dispatcher said that so many cars unknowingly drove through the 30-foot spill in the afternoon that fire and highway officials were unable to clean it up. By the time traffic slowed down, the spill had hardened, and officials decided to leave it in the road and clean it overnight.

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