Does locking rolling stock anhydrous ammonia tank valves make sense or is it too much of a headache as farmers in North Dakota apparently contend?

North Dakota state officials and law makers are ready to rescind a law/regulation from 2003. It required farmers and anhydrous ammonia dealers in portions of the state to put locks on the valves of NH3 tanks used to apply the fertilizer when the tanks were left unattended, especially over night or in fields for a day or longer waiting to be used in applying the fertilizer.

State officials never did enforce the law as no records show the $100 fine being levied for a first-time offense, according to state reports about the regulation and enforcement. The same state officials claim theft of NH3 for the use in making methamphetamine has declined quite drastically without worrying about tight security of NH3. The state’s criminal charges for methamphetamine manufacture or “meth labs” reportedly dropped from about 300 in 2003 to less than 10 in 2010. The contention is that the 2005 law restricting the sale of pseudoephedrine drugs (another necessary ingredient for meth manufacturer) by pharmacies is the reason for the drop in meth lab operations and arrests.

“It was becoming more of a hindrance to the industry than it was stemming anhydrous thefts,” Spencer Wagner, fertilizer specialist with the North Dakota Agriculture Department, is quoted as saying in an Associated Press article.

In public comments about whether to end the tank security, farmers complained about the time it took to unlock tanks and about lost lock keys.

There are questions this report from North Dakota raises. Are locking NH3 tanks necessary, a wise move for safety, a wise move because meth manufacturing continues or completely unnecessary in any or all farm states?