Calcium Chloride - Dust Suppression

[KRSServices]

I have used calcium chloride for years as a temporary dust suppressant and stabilizer. The Federal government has deemed salt as toxic (to certain species of fauna and fish) and this includes calcium chloride. My question pertains to the chemical reactions that take place in the soils when the calcium is entrained in the road gravels (road surface). Does the product degrade or react with the soils to become "less toxic" over a period of time. I realize that continued moisture reduces the effectiveness as a dust suppressant, but is the material changed chemically or simply lost (to runoff) into the ditches? I have to make a presentation on the subject, and I know that will be a question some astute councillor will ask. Any ideas? KRS Services

http://www.krs-services.com

 

[Isadore]

KR: Probably a little late here. Calcium Chloride (CaCl2) readily dissolves into the respective ions (Ca++ and Cl-)when it comes into contact with water. Salt toxicity is a matter of concentration. Obviously low levels of Ca++ and/or Cl- are nothing to worry about; the toxicity arises when it reaches tributaries as a "slug" or stream high enough in concentration to upset the osmotic equilibrium (salt balance) of fresh water invertebrates, fish, etc...

Dilution of CaCl2 surely lowers its overall toxicity. Again, its a matter of concentration levels. Ca++ and Cl- are, for the most part unreative; they may "adsorb" to soils (e.g., Ca++ to clay particles); but it does not enter into chemical reaction per se.

 

[PBroad]

The big problem is the chlorides. A parallel thread is running on alternatives. Come to

http://www.eng-tips.com/gviewthread.cfm/lev2/8/lev3/41/pid/158/qid/29245

to view.

(environmental Mining issues)