CMA
What is CMA?
CMA is an ice-melting product that is formulated with Calcium, Magnesium and Acetate.
Why were Chloride Ice Melters (CMA) developed?
There has been a concern for damage to the environment and to structures like bridges and parking garages caused by the use of chloride de-icers.
In the 1970's, the Federal Highway Administration (FHWA) identified calcium magnesium acetate as the only low-corrosion chemical alternative to road salt that also protected the environments. Years of research and field applications have proven CMA is no more corrosive than tap water and does not harm vegetation or receiving waters.
Does CMA affect the environment?
When absorbed into the soil, CMA's calcium and magnesium components benefit the soil structure; just as liming a garden improves permeability. The acetate portion of CMA biodegrades naturally.
Does CMA cause corrosion on roads, bridges, parking garages, ect?
No significant corrosion of steel, aluminum, or concrete has been found in repeated tests with SMA sponsored by the FHWA, states, and private researchers.
Is there government awareness of CMA?
In 1991, Congress passed the Intermodal Surface Transportation Efficiency Act (ISTEA) providing states with 80% reimbursement for use of CMA on bridges, overpasses and approaches.
|
Enviromental Impact |
CMA |
Chloride Ice Melters |
| Soils |
Biodegradable in soil. No adverse effect on soil compaction and strength. Increases soil permeability. |
Breaks down soil structure, increases erosion. Causes soil compaction, which decreases permeability. |
| Vegetation |
Little or no adverse effect. May stimulate
plant growth. Acetate ion is the most
abundant organic acid metabolite found in
nature. |
Osmotic stress and soil
compaction harm root systems.
Spray causes foliage dehydration
damage. Many plant species are salt sensitive. |
| Groundwater |
Poor mobility in soil, unlikely to reach
groundwater. Ca, Mg increases water
hardness. |
Mobile Na and CI ions readily reach groundwater. Increases Na and CI concentrations in well water along with alkalinity and hardness. |
| Surface Water |
Potential for oxygen depletion through
biological oxygen demand (BOD) at
concentrations greater then 100 ppm in
closed systems. Decomposes in 5 days at
20 C, 10 days at 10 C, 100 days at 2 C.
Will not stimulate algae growth. |
Causes density stratification in
ponds and lakes, which can
prevent reoxygenation.
Increases runoff of heavy metals
and nutrients through increased erosion. |
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