Pass the Salt: Efficient Snow & Ice Management
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2018 Pass the Salt: Efficient Snow & Ice Management Infor- Anti-Icing NH Best Management Practices A Proactive Treatment Anti-Icing before a storm is very similar to GET OUT EARLY using a non-stick spray on a pan before Typically anti-icing is most cooking. Just like a non-stick spray prevents effective if applied 1-2 hours food from bonding to the pan, anti-icing pre- before the precipitation be- vents snow and ice from bonding to the pavement so that it can be plowed away. gins however it can be ap- Anti-icing can save you money as it costs plied up to 24 hours in ad- 50% less than reactive deicing. vance. TRY IT FIRST Make Your Own Salt Brine Trying anti-icing for the first When making brine it is important to add enough salt to produce a 23.3% solution time? Make a 23.3% brine which freezes around 0°F. Roughly 2.5lb per solution and before a storm gallon of water will produce a 23.3% solution. spray pavement on your own You can verify using a salometer (~$20) a property using a masonry/ 23.3% solution will have a specific gravity of plant sprayer. Use this ex- 1.176, or 85% salinity. Consult the Brine Mak- ing BMP sheet for more info. periment to determine how best to use it with your cli- ents. How Much Should I Use and When? LEAVE SOME You can apply brine up to 24 hours in advance PAVEMENT BARE of the storm. Typical application rates range It’s always best to use from 0.5 to 0.75 gallon per 1000 sq.ft. (10’ x 100’ area). Other chemicals such as magnesium are stream nozzles instead of also available—consult your supplier for applica- fan tip to avoid creating a tion rates. Anti-icing is not advised prior to freez- slippery condition. If the anti- ing rain events. icing liquid freezes the bare pavement will still provide a Getting Started traction surface. Try making your own salt brine by putting 13 lb of salt in 5 gallons of water to get a 23.3% salt brine USE A FILTER solution. Mix the brine until all of the salt is dis- solved. Using a masonry sprayer apply the liquid Having a filter in your liquid several hours before a storm. Start by applying dispensing system will re- about 0.25—0.5 gallons to a 10’ x 50’ area. Adjust duce clogs in your nozzle. the application rates based on your experience. Automotive in line fuel filters Being careful not to over apply and cause a slip- pery condition. work quiet well. If your liquid Produced in partnership with: dispenser is not functioning properly be sure to check the filter first. Information Technology SolutionsPre-wetting NH Best Management Practices Getting Started Wet the pile! There are two ways to pre- PRE-WETTING? wet your de-icing chemicals. The easiest way to get started with pre-wetting is to Pre-wetting is the process of spread your salt pile, spray it with pre- coating a solid de-icer with a wetting liquid, mix it around, and re-pile it. liquid before it is spread on a More advanced truck mounted pre-wet roadway. systems can be installed on your trucks if you decide to make the investment. WHY PRE-WET? De-icing chemicals must form a brine before they can begin melting ice. Pre-wetting your Pre-wetting Liquids chemicals accelerates the You have a few options for pre-wetting liquids. brine making process, which The most commonly used is a 23% sodium chlo- improves the melting action of ride brine solution. Calcium chloride at 32% solu- tion is also used, as well as Magic Minus Zero™ the material. Pre-wetting also and other patented products. reduces bounce and scatter Source: Wisconsin DOT Transportation Bulletin of material during spreading, and reduces the total amount Spraying the Pile Truck Mounted Systems of de-icer needed to obtain This is the easiest and most cost effective way These systems are mounted in the truck bed to get started in pre-wetting. The first step is to and coat the de-icer with liquid as it comes the desired results. spread your salt pile on a flat, impermeable off the conveyor/auger onto the spinner. surface. Next, spray the salt while it is spread These systems have the benefit of applying REDUCED RATES out, and mix it around to ensure adequate and liquid only to the material you use as you If you are pre-wetting, don’t consistent liquid coverage. After the salt is suf- use it. However, these systems must be in- forget to reduce your applica- ficiently covered, re-stack the salt in your stor- stalled on every truck that will be used to age shed for later use. spread pre-wetted material. tion rates accordingly. Reduc- tions in the range of 15-20% are typical. HOW MUCH LIQUID? A good rule of thumb is to use 8-10 gallons of pre-wetting liquid for every ton of de-icer. For other chemicals, such as magnesium chloride, consult your supplier for application Produced in partnership with: rates Infor- How Salt Works NH Best Management Practices How Do We Melt Ice? Ice can be melted by increasing the temperature, BE PROACTIVE - or lowering the freezing point of the water. It’s not ANTI-ICE cost effective to use heat to melt ice on our roads so we use chemicals to reduce the freezing Anti-icing is the proactive point—anything that will dissolve in water will method of preventing snow work, including: salt, sugar, even alcohol! and ice from bonding to pavement. It can be more than 50% more efficient than Why Use Salt? deicing. See the NH Anti- Salt (Sodium Chloride) is the cheapest and most Icing Factsheet for more in- readily available chemical that efficiently melts ice and can be easily applied to our roadways and park- formation. ing lots. However salt does corrode our cars and bridges, contaminates drinking water and pollutes our PRE-WETTING FOR streams. Alternatives include potassium acetate, and FASTER ACTING calcium magnesium acetate (CMA), — all of which SALT are considerably more expensive than calcium chlo- ride, and have their own environmental concerns. Adding brine to salt before you apply it to pavement jump starts the melting pro- Brine Makes It Happen cess which means your The first step in melting ice is the formation of a pavement will be clear soon- brine. Salt crystals pull water molecules out of er. See the Pre-wetting Fact ice formation which creates a brine with a lower Sheet for more information. freeze point. Once the brine is formed melting is greatly accelerated. Save time and money by pre-wetting your salt with a brine before it hits KNOW YOUR LIMITS the pavement to jump start melting! See the Pre- Dry salt becomes ineffective Wetting fact sheet for more information. Source: Wisconsin DOT Transportation Bulletin #22 below 15°F if possible wait until the temperature rises Save $$ and the Environment before applying salt. At 30°F In New Hampshire there are over 40 watersheds cur- 1 lb of salt can melt 46.3 lb rently contaminated from road salt. As the pavement of ice in 5 minutes. At 15°F 1 temperature drops more salt is required. As the pave- lb of salt can melt 6.3 lb of ment temperature rises less salt is required. Save mon- ice in 1 hour. ey and the environment by using only what is needed to do the job. See NH application rate charts for recom- mended rates. PLOW FIRST Always plow before applying any kind of chemical deicer Produced in partnership with: to avoid pushing it away! InformationMaterial Technology Storage and Solutions Housekeeping NH Best Management Practices Proper Material Storage Proper storage of materials (especially IMPERMEABLE SUR- chemicals) is essential. If impermeable sur- FACE STORAGE faces are NOT used in your storage facili- Store salt and liquids on an ties and brine infiltrates the ground or impermeable surface to pre- groundwater, you need to register with the DES under the Groundwater Discharge Per- vent groundwater contami- mit and Registration Rules, Env-Wq 402. It nation. is a free registration used for tracking poten- tial contaminant sources. COVERED STORAGE AREAS Secondary Containment If possible, store your salt in Secondary containment for your liquid storage is a HIGHLY recommended technique to help a covered shed to prevent reduce soil and groundwater contamination. If runoff. If there is not a shed a tank Begins leak, the secondary contain- available, cover your salt pile ment prevents liquid from seeping into sensi- well with an impermeable tive environments. membrane or tarp. SECONDARY CON- TAINMENT Liquid Storage Keep your liquids in an ap- Brine stored using holding tanks must be propriate storage container. managed so that there are no releases Secondary containment to drains, groundwater or surface water. should be used incase a leak develops in the primary con- tainer. PROPER DRAINAGE & COLLECTION NHDES Fact Sheet DWGB-22-30 Protect your ground water This fact sheet outlines the basic required specifi- cations for salt and chemical storage facilities. For supply! A drainage system additional information, please contact the Drinking should be in place to collect Water and Groundwater Bureau at (603)271-2513 runoff from your salt pile, as or [email protected], or visit their website at: well as to collect any liquids http://des.nh.gov/organization/divisions/water/dwgb/ that may escape contain- index.html. The Salt Storage Handbook contains more information and guidelines that should be ment.