By the time salt is spread on roads, it can already be millions of years old. Thankfully for motorists and snow removal companies, intact salt never loses its ability to melt ice, which means salt does not have to be used immediately. Salt that has been stored is just as effective as the salt that has been recently removed from a mine. But, to be able to use road salt from one winter to the next, proper storage is crucial.
When it comes to proper storage, do not cut corners. Know what your local, state, and federal storage requirements are. The laws are there for a reason – to ensure worker’s safety, the public’s safety, and the safety of the environment.

The Science of Storing Salt

Because salt does not lose ice melting capacity to the air, the main enemy of salt is precipitation. Stockpiles of salt should never be exposed to any types of rain or snow, from both above or below. One of the essentials of proper storage involves keeping the salt stockpiles on waterproof pads, either in a building, which is recommended, or covered by weather resistant materials such as tarpaulin. You must also be cautious of high humidity. Salt can absorb moisture from the air when humidity is above 75%. Although the moisture that is absorbed will likely evaporate over time, the affected salt will clump and a layer of crust will result on the outside layer of your pile. This can be significantly reduced by storing properly and nearly eliminated when stored indoors for the long term.

Best Storage Option

Proper storage inside a building or under cover will also prevent possible detrimental effects on the environment. In order to eliminate the possibility of contaminating groundwater, store away from wells, lakes, rivers, drains, and ditches. When storing salt indoors, be sure the floor is sloped away from the door and sweep the haphazard salt back into the pile. Outside, do not keep the salt downhill from a snow pile. The melting snow can lead to runoff.

How Much To Store

The last question is how much salt should a snow removal company store? Since preparation is key, at minimum keep the amount of salt you spread during a typical winter. Don’t count on a weather forecaster’s prediction of a mild season. By possessing enough salt to handle an average winter’s needs, a company can eliminate the need for stockpile replenishment during the heavy demand periods caused by severe weather. Another benefit of an adequate supply is the avoidance of steep delivery prices on emergency shipments. When a resupply is necessary during the winter months, be sure to order before your inventory is depleted. After all, if not all of the requested salt is used by the end of winter, with proper storage the salt will continue to be effective and combat the effects of the upcoming winter. Millions of years have proven this so.

RULES OF THUMB:

1. Better Safe Than Sorry
2. Store salt on a concrete or asphalt pad raised a few inches from the surrounding terrain if possible and sloped to your runoff holding area
3. Use sand bags or a trench around your pile to stop runoff from contaminating the base of your pile.
4. Any water that seeps under your pile may evaporate in to your pile, the resulting humidity will clump/crust your salt  surface.
5. Store indoors if possible.
6. Cover your pile with a tarp ALL the way to the base  and extend a few feet out to the edge of your pad, trench or sandbags.
7. Store salt OVER 50ft away from water ways (or according to your local regulations) with proper blocking to avoid runoff contamination.
8. Never store your pile in a depression in the terrain. You may contaminate the bottom of your pile and/or you will contaminate runoff.
9. Do not store your salt near large piles of snow that can create melt puddles near your pile.
10. Be sure to clear storm drains from blockages to avoid floodwaters getting to your pile.
11. Be sure not to store in a “100 year flood plain” .
12. You must collect and store any salt contaminated runoff ( from the pile or loading areas ).
13. REPORT contaminations to the proper authorities. ie Local Water Bureau, EPA, Local Health Department.