Environmental Sustainability for Your Asphalt Pavement

 

The future of our private and public infrastructure and the demand on finite natural resources will be best served once people understand how the right maintenance products, used at the proper time, will help save the environment, and money.

Rejuvenation transforms an expense to an asset. This investment in the property has been proven to save thousands of dollars by significantly extending the life of your pavement by as much as 300%. Rejuvenating the existing asphalt is an environmentally friendly alternative to milling and repaving, which has a negative effect on the environment by releasing greenhouse gasses, and leaving a carbon footprint casued by the manufacturing, transporting, and the installation of the asphalt material.

Your pavement inventory is one of the most critical physical assets that impact your association's capital reserve dollars. Effective management of that pavement saves you money; every $1.00 spent on pavement preservation saves $6 to $10 dollars on future repairs and replacement.

All Rejuvenators Are Not the Same

The first two part rejuvenator was manufactured by a coal tar emulsion seal coating comapny about 20 years ago. The company had to increase the percentages of solvent used, which changed the dynamics of the rejuvenator, due to the improper amount of tar oil (the third component), to rejuvenator. This resulted in the increase of insoluble carbon solids by 40% into the 17 to 22 range. The balance of the higher carbon solids now remains on the surface of the pavement, the same carbon solids that are plaguing the coal tar emulsion industry.

A product called Conditioning Pavement Rejuvenator (CPR), is in the pavement, not on it, with only a small amount of carbon solids (5%) remaining on the surface of the pavement. It is a three component product and has approximately 4 times less carbon solids that are contained in a two part rejuvenator; it provides greater and deeper penetration and replaces the evaporated asphalt oils from the oxidized pavement.

Why Asphalt Pavements Deteriorate

Asphalt deterioration is a chemical, as well as a physical process. It is the chemical aspect that people fail to recognize when planning a pavement maintenance program. The exposure to UV rays from the sun is devastating to your pavement. Oxidation chemically alters the asphalt binder, the glue that holds the mix of sand and stone together. This oxidation effect makes the binder hard and brittle and prone to raveling (releasing of stone and sand). The surface then becomes rough and cracks form.

CPR replaces the asphalt's oils lost through oxidation. It penetrates the surface 3/8 to 1/2 inch, which improves the actual condition of the asphalt. It stops the raveling and keeps the pavement flexible and provides superior fuel resistance. CPR has been extensively tested by the Army Corp of Engineers along with various state agencies. It meets the FAA's latest P-632 specification, and is used on airfield pavements worldwide as well as parking lots for commercial industries, shopping centers, office buildings, apartment complexes, and condominiums.

Seal Coating

Right or wrong, it is not the intent here to discuss the strenghths or weaknesses of emulsion seal coats currently being used, either the newer asphalt emulsions or the widely used coal tar sealers. The coal tar selaers have been under fire since 2005, when a study was done in Austin, Texas. The theory was that the dried residue washed off and was a significant contributor of high carbon solids in the Austin area streams and waterways. The use of coal tar selaers was consequently banned. According to an article this year in APE (2016 Allied Paving Equipment Publication), the use of coal tar emulsions have been now banned in at least 15 states so far. It is noted that sealer produced with asphalt emulsions is also toxic, though less so. Keep in mind that all emulsion seal coats lay on the surface of your pavement and at some point they will wear off and be washed down the drain!

By working together, and recognizing the importance of education of new technology, we are doing our part to help save our resources and our environment.