Robert E. (Bob) Winters Treasurer and Member of the Board of Directors Rubber Pavements Association PresidenVCEO Atlas Rubber, Inc.

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1 ~The use of Crumb Rubber Modifiers (CR M) in Asphalt Pavements" Robert E. (Bob) Winters Treasurer and Member of the Board of Directors Rubber Pavements Association PresidenVCEO Atlas Rubber, Inc. For presentation at Scrap Tire '96 The Scrap Tire Management Council Conlerence Chicago, Illinois August 16&

2 My name is Bob Winters. I am the PresidenVCEO of Alios Rubber, Inc., Los Angeles, California. I also currently hold the position of treasurer and board member of the Rubber Pavements Association (RPA). I was one of the founding members of the Asphalt Rubber Producers Group (ARPG), the group which was succeeded by RPA. I served as secretaryltreasurer of ARPG for two years and for the years 1987 and 1988 as its presidenvchairman. Many of you may be unfamiliar with RPA. RPA is a national nonprofit trade association that promotes the use of crumb rubber modifier in asphalt pavement construction and maintenance applications in the United States. Our office is located in Washington D.C., with plans to relocate the headquarters to Phoenix, Arizona, while still maintaining a working presence within the bellway. We represent approximately twenty companies, both crumb rubber producers and asphalt paving contractors, and our combined membership represents between 70% to 80% of the crumb rubber modifier work being done in the United States. We are very active in technology transfer initiatives and in Federal, State and private industry research initiatives. RPA serves as a resource to State Highway Transportation Agencies, start-up CRM companies, and researchers and students in search of technical information regarding the use of CRM technologies. I thought I would begin by reviewing the historical development of CRM technologies in the United States. The high rubber percentage use of recycled tire rubber, or crumb rubber, in asphalt was developed in the early 1960's by Mr. Chanes H. MacDonald, a materials engineer then working for the City of Phoenix, Arizona. At the time, Mr. MacDonald was searching for beller methods of patching and repairing cracked asphalt and concrete pavements. Mr. MacDonald was indeed successful in his efforts to react crumb rubber with paving grade asphalt cement in a timeltemperature process. This process was licensed exclusively to Atlas Rubber while the patent(s) were still pending. Atlas undertook the prosecution of the patent(s) and the efforts to promote the use of Mr. MacDonald's composition(s) commercially. This process was eventually patented in The addition of crumb rubber allowed for a more flexible binder and provided a surface that was more durable and acted as a waterproofing membrane over severely cracked pavements. J think it is important to recognize that from the beginning, this technology was promoted on the in-place properties of the material. Unlike the political pressures at work over the past 10 or 15 years, the recycling of scrap tires was not a leading motivation for Mr. MacDonald's work with crumb rubber. Its remarkable in place performance in retarding or eliminating crack reflection was his prime objective.

3 The success of the Asphalt-Rubber membrane led to its use as a crack and joint sealant. The most widely used crack and joint sealant in the U.S. is a CAM/polymer blended product. During the 1970's, Asphalt-Rubber was fu rther developed to be used as a binder in asphalt cement hot mix surfaces. The result was a product with superior resistance to cracking and aging as well as a longer service life and measurable cost effectiveness. In 1976 the United States Federal Highway Administration (FHWA) placed Asphalt Rubber on ~ E xperimen t al Status~. This was, in part, due to the fact that the Asphalt Rubber was a patented product at that time. Being placed on Experimental Status meant that federal money was not available to States to build CRM pavements. Since States are heavily dependent upon federal funding for road construction projects, this obviously hurt the market development for CRM products. Research and development as well as growing commercial use of Asphalt-Rubber continued, however, throughout the 1970's and 1980's. Advancements were made in th e equipment used in the application of CRM technologies and new innovative ways were developed to use Asphalt-Rubber. Despite limited federal funding, several States were particularfy inspired and diligent in their efforts to recognize the full engineering potential of these technologies. Arizona, Florida, Texas and California, for example, were cl early leaders in this area. Over the next several years, many projects were constructed across the United States. Today, these projects have been in place long enough to prove the in-place properties of Asphalt-Rubber. It was not until 1991 with the signing of the Intermodal Surface Transportation and Efficiency Act, the so call "ISTEA" act, that Asphalt-Rubber was taken off of ~Experimental Status". As I mentioned earlier, this meant that States could th en choose to use federal funding to build CRM pavements. In fact, crumb rubber is classified as a -modifier" by the Federal Highway Administration (FHWA), not an "additive-, because of its ability to enhance the performance of asphalt pavements. As many of you are aware, in 1991, as part of ISTEA, the U.S. Congress passed a law which mandated the use of CRM by State Departments of Transportation in growing percentages of asphalt pavements using federal funds. The 1991 ISTEA Act, however, was not the first attempt by the U.S. Congress to promote the use of Asphalt Rubber. Incentives for States to accelerate research efforts pertaining to the use of Asphalt-Rubber were included in both the 1982 and 1987 Surface Transportation bills. Section 1038 was, in fact, the culmination of over a decade of Congressional encouragement for States to examine the benefits of using ground tire rubber in asphalt pavements. It should be noted that the CRM community did not ask to be included in Section APA has never believed in mandates. Rath er, it was the product of the U.S. Congress' desire to improve our nation's roads, while simultaneously addressing a critical solid waste issue. The CRM industry did, however, attempt to provide guidance to Congress during the drafting of Section 1038, and tried without success to change the

4 mandate to an incentive program, which we felt would be more palatable to the public sector engineering and administrative community, You may be aware that Section 1038 was never funded by the Transportation Sub Committee on Appropriations, nor was it enforced. During the last Congressional cycle, Section 1038 was repealed. Despite the repeal of the federal legislation, several States continue to use CRM products in certain construction applications. I think the members of RPA would agree that federal legislation regarding the use of CAM products has been both a blessing and a cu rse. The federal legislation dramatically raised the profile of this relatively modest industry in the United States. Not all the attention, however, has been positive. The CAM industry, to a certain extent, has seen a backlash over the last several years due to the presence of the federal mandate on the use of CRM. The public sector engineering community prefer to use pavement materials based on engineering merit and frankly resented the mandate to use CRM or suffer a funding penalty. On the other hand, the legislation has certainly served to accelerate much of the ongoing research on CRM technologies. It would be difficult to hazard a guess as to what effect the legislation has had upon the CAM industry in the U.S.. I think one would have to conclude that in some respects the effect of the legislation has been both good and bad. One thing is certain. Based on Section 1038(d) many entrepreneurs and investors saw this as "an opportunity to make profits." Many startup crumb rubber facilities were established with little or no market research data other than the Federal mandate. In addition, those of us already in the crumb rubber business, expanded their operations and capacity. Some established new operations at other locations around the U.S. As a result, when the mandate was repealed, a much larger industry capacity (of those who survived) is now competing for the existing markets. This increase in capacity has created a competitive situation in which discou nting and price cutting is now common. Only the strong and diversified will survive in the slower growth, but more orderly, market. Those who use their own crumb to make and market finished products are less vulnerable in this situation. On a more positive note, Asphalt-Rubber has been used in nearly every road condition, in nearly every climate across the United States. CRM is used to build longer lasting, lower maintenance roads in a cost effective manner. It is a proven technology with sound engineering benefits. It's growth, however, is forecast to be gradual. I have brought with me today a list of crumb rubber statistics that I hope will shed some light on the U.S. crumb rubber modifier market.

5 CRUMB RUBBER STATISTICS 250 million tires enter the waste stream in the U.S. each year Approximately 10 million tires were recycleq into CAM HMA in 1995 Approximately 500,000,000 tons of Hot Mix Asphalt were laid in the United States during the 1995 paving season. Only 1 % of this was CAM HMA Use of CAM products in HMA applications grew by approximately 5-10% during 1995 Virtually 100% of the CAM pavements constructed in the U.S. were designed using the pre-reacted process Over 45 states have experimented w/crm pavement applications and several states use CRM technologies routinely The state of California used approximately 1,000,000 tons of A-A during the 1995 paving season The state of Florida uses CAM in 100% of it Open-Grade friction courses Over the lasl 5 years, the cost of a ton of A R binder has been cut in half In 1995, the average cost for a ton of CRM asphalt binder (pre reacted) was approximately $ In 1995, the average cost for a pound of 20 mesh CRM was approximately $.15 In 1996 the average cost of 20 mesh dropped to $.13 to $.14 lb. The cost for 10/30 material has dropped from $.15 to 17 lb. in 1994/95 to $.12 to., 3 lb. for 1996 By the year 1999, the United States government will have invested well over $10,000,000 for research on CRM technologies More federal money has been spent researching the performance, recyclability, and emissions of CRM HMA than on all other asphalt pavement modifiers combined

6 CONCLUSIONS 1.) THE CRUMB RUBBER INDUSTRY IN THE UNITED STATES HAS FINALLY REACHED A POINT WHERE THE CONTRACTING COMMUNITY AT LARGE RECOGNIZES THAT CRUMB RUBBER CAN BE CONSIDERED A MODIFIER VERSUS A WASTE MATERIAL. THE VAST WEALTH OF LABORATORY AND FIELD DATA THAT HAS BEEN COLLECTED OVER THE PAST TWENTY YEARS HAS MADE THIS A REALITY. 2.) THE USE OF CRM PRODUCTS IN THE PAST, AND IN THE FUTURE WILL CONTINUE TO BE BASED UPON THE ENGINEERING CHARACTERISTICS OFTHE MATERIAL. IT IS FOR THIS REASON, THAT THE USE OF CRUMB RUBBER BY STATE HIGHWAY DEPARTMENTS SHOULD CONTINUE TO GROW SLOWLY IN THE UNITED STATES. 3.) IN ORDER TO REMAIN COMPETITIVE, IT WILL BE IMPORTANT FOR THE CRUMB RUBBER MODIFIER INDUSTRY TO CONTINUE TO WORK WITH THE FHWA TO VALIDATE THE PERFORMANCE OF CRM BINDERS IN THE STRATEGIC HIGHWAY RESEARCH PROGRAM (SHRP) AND OTHER FEDERALLY SPONSORED RESEARCH PROGRAMS AIMED AT IMPROVING THE PERFORMANCE OF ASPHALT PAVEMENTS IN THE UNITED STATES