Phosgene would have been at VERY low levels. And, it's not a stable compound. It didn't just disperse (which, it would.. to levels that wouldn't harm anyone) It chemically breaks down to CO2 and HCl.
The HCL is acid, but would be also be at VERY low levels. It would quickly be neutralized by normal bases in the soil. Effectively, it would mostly be converted to NaCl. .. or salt.
You don’t speak sarcasm too well, do you?
Its my primary language bro.