You can go online at Costco.com and apply for a Costco Membership there by adding it to your shopping cart if you are shopping for the first time. Your membership card will be mailed to you within 7-10 days but you can actually shop at the online store immediately.
The three most common chlorine-containing substances used in water treatment are chlorine gas, sodium hypochlorite, and calcium hypochlorite.
Chlorine is a toxic chemical. It is used in water treatment to reduce and kill forms of biological agents, such as bacteria and viruses found in water systems. Chlorine is harmful to you when you drink it and when it is absorbed into our skin and inhaled into your lungs when you shower.