Including limestone in gravel roads has its benefits and drawbacks. Here’s what you need to know before deciding what route will best suit your needs.
While the low cost of gravel roads makes them a popular choice, constant upkeep is necessary to keep dust and erosion in check. In order to strengthen unpaved roads and minimize deterioration, many contractors introduce a proportion of limestone into their gravel mix. Considering incorporating limestone into your roads? Read on for more information on the major pros and cons, so you can make an informed decision when the time comes.
Pros: Hardness & Strength
Limestone displays two crucial characteristics: it is harder than most types of gravel, and its unique binding properties, which set it apart from other types of stone, contribute to a stronger road surface. The Wisconsin State Journal reports that when cars drive on limestone, the chunks of rock rub together to produce a fine dust. This dust is water soluble, meaning that when the water evaporates, it will leave the minerals behind. These particles act like glue, binding the gravel together.
Cons: Cost & Dust
Cost is a primary consideration when deciding whether to include limestone in your gravel mix, as limestone costs $18 per ton to gravel’s $9.50 per ton.
Another con: remember the dust we mentioned above? Those fine particles don’t pose a problem when the weather is wet, but in the dry summer months, dust can become a real issue. This is especially true in America’s drier areas, where humidity is so low that, when it does rain, the water rapidly evaporates.
The Forester Network’s Erosion Control Weekly outlined the potentially deleterious effects of dust from limestone tracks on the environment, community, and for regulation. One such drawback: dust lowers visibility on the road, increasing the chance of accidents. The increased likelihood of respiratory diseases like asthma resulting from dust inhalation are an additional risk. Some regulations are already in place to combat these concerns: states like Nevada and California require companies to prevent dust emissions from affecting waterways, while the Clean Air Act places strict controls on the levels of PM10 (a dust particle size associated with certain health problems) that can be released into the environment.
So the question remains: how can you take advantage of the benefits of limestone while keeping dust (and your budget) in check?
How Can Midwest Help?
Road Pro NT®
Midwest Industrial Supply, Inc.’s RoadPro NT® is the perfect way to address the weaknesses of a limestone road, which is why James Bellamy, superintendent of the maintenance department for PTC Alliance, recommends it. RoadPro is a modified asphalt solution, engineered with Midwest’s chemical expertise to create a product superior to traditional asphalt.
RoadPro will bring roads into compliance with the Clean Air Act, locking in dust and dangerous PM10 particles. Moreover, this product does not weaken with moisture (as limestone does), and it is specially formulated so that it won’t become tacky in the heat ( as conventional asphalt does). In addition, Road Pro will create a surface that is strong enough to handle large equipment without damage.
Dust Fyghter® LN100
Dust Fyghter uses a natural and sustainable formula to create a firm, stable road surface that holds dust in place. This product will also lengthen the lifespan of a road, reducing the need for repairs due to washboarding or potholes. Dust Fyghter is made from lignin, a naturally occurring and abundant substance found in trees which sticks dust particles together so that they can’t escape into the air.
It seems, given their drawbacks, that limestone roads aren’t really a solution in themselves. Modern environmental needs and dust regulations mean that untreated limestone roads present difficult environmental and safety challenges. With Midwest’s dust control solutions and manager services, you can protect both your investment and the environment.