Penoxsulam is another ALS inhibitor. Its spectrum of weed control and mode of action is similar to Celsius or metsulfuron. Difference is that it will work if applied on granular fertilizer. I do believe it does move a little in the soil, but only enough to reach weed roots. Cool season grasses are not as tolerant of penoxsulam as warm season grasses. Rate limit of 0.02 lbs per acre. A cool season blend needs to have lots of 2,4-D and dicamba in it to tone it down, as well as work on the weeds.
My definition of folly is spraying atrazine or simazine on pure sand in a high rainfall area. For one thing, under those circumstances trees and shrubs are not safe. Secondly, it is almost guaranteed that those chemicals will leach down to ground water. Especially if the weather pattern is a 2-5" thunderstorm every single afternoon from June to October. This leaching hazard is yet another reason why I will not touch an irrigated lawn where the property owner insists on controlling the irrigation. People do set controllers to put down close to an inch per day when only an inch or so per week is needed.
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
Benjamin Franklin 1775
Sell not virtue to purchase wealth, nor Liberty to purchase power.
Benjamin Franklin Poor Richard's Almanac1738