Interesting Digging at Joliet Train Yard

I am curious to see what is the intended use for this huge pit.... Why would a train yard be digging a pit that, from a distance IMHO, appears to be six (6) feet deep and 50x100 feet at longest points... Maybe the train yard is putting in a fancy retaining pond, what with the perfectly flat bottom and tightly packed sloped sides... Wonder if they'll include a lovely fountain? Then, on the other hand, it could be intended for other purposes... What do you think? Drive by, take a good, long look... then leave a comment below! Would love to hear your thoughts!

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