Document NeDdk1nzN20vxgRmaVxZRpqw8

ASARCO Central Research Department South Plainfield, N.J. 07080 NOV L 6 $78 November 15, 1978 REF: 1188 Mr. E. Martinez BUILDING Subject: Asbestos-Cement Pipe Producers Association (AACPP) Meeting in Arlington, Virginia on November 8, 1978, to Review the Aggressive Water Guidelines for Asbestos-Cement Pipe Participants: Mr. Mr. Mr. Mr. Mr. Mr. Mr. Mr. Joseph Jackson, AACPP Bert Cook, Atlas Asbestos Corp. Fred Hawkins, Certain Teed Corp. Roman Korbij, Certain Teed Corp. John Herr, Johns-Manville Corp. Hugh Frazer, Canadian Johns-Manville Lee Taylor, Capco Victor Puskar, ASARCO Incorporated Purpose of the Meeting: To review the aggressive water guidelines presently used for asbestos-cement pipe. tr * Introduction: The aggressive index, which takes into account the pH, hardness, and alkalinity of the water, is used to determine the appli cability of a/c pipe for.water supply systems. Generally, soft, acid waters attack the pipe resulting in slow erosion of the pipe and release of fibers. The use of a/c pipe for these waters is not recommended. Hard, alkaline waters, on the other hand, deposit a mineral coating on the pipe surface and virtually prevent the release of any fibers. Numerous exceptions to the validity of the aggressive index have been observed. The purpose of the meeting was to review the validity of the aggressive index and, in particular, to discuss the data presented in the Johns-Manville research report, "Study of the Effects of Aggressive Waters on Transite Pipe." The ultimate long range objective would be to establish more- accurate and universally valid guidelines for the use of a/c pipe. Possible health hazards due to the presence of asbestos fibers in drinking water are greatly contributing to the urgency of the problem. In contrast to the inhalatipn of airborne asbestos ASARCO ALV 0000918 Hr. E. Martinez -2- fibers, a clear cause and effect relationship between ingested asbestos and gastrointestinal cancer has not been established. In spite of the lack of any concrete evidence, steps are now ' being taken by some "prudent" public officials and consumer ad vocates to restrict the use of a/c pipe. Some municipal and county ordinances now prohibit the use of a/c pipe, and a bill has been introduced in the Virginia state legislature to pro hibit a/c pipe in water distribution systems throughout the state. The Environmental Protection Agency, so far, has not issued any regulations on either the use of a/c pipe or the permissible quantities of asbestos present in drinking water. An EPA spon sored study to establish a correlation between ingested asbestos and incidence of cancer by feeding asbestos to laboratory animals is presently under way and the results should be available in the spring of 1979. Regardless of the outcome of this study, it is believed that some restrictive regulations by the EPA will be forthcoming in the near future. Summary of Discussions: The discussions centered on the validity of the aggressive index. The aggressive index is defined as AI = pH + log (AH), where pH = index of acidity (or alkalinity) of the waterstandard pH units. A *= total alkalinity - ppm as CaC03. II = calcium hardness - ppm as CaC03. American Water Works Association (AWWA) Bulletin C400-77 defines the aggressiveness of waters as follows: AI *= <10.0 : highly aggressive. AI ** 10.0 - 11.9 : moderately aggressive. AI = l2.0 : nonaggressive. Mr. Jackson (President, AACPP)^ as well as other participants, pointed out that numerous exceptions to the validity of the ag gressive index have been encountered. Erosion of the pipe and fiber release have been observed in several installations where, according to the aggressive index of the water, no erosion should have occurred. Also, naturally deposited protective coatings have been found in a/c pipes carrying low pH, low hardness water, i.e. water classified as highly aggressive. I ASARCO ALV 0000919 Mr. E. Martinez -3- It was the consensus of opinion that other parameters besides pH# hardness and alkalinity are also affecting the erosion of a/c pipe and the release of fiber. These additional con tributory factors and their interactions are not known. The importance of a thorough understanding of the erosion and fiber release mechanism was stressed in anticipation of future regu latory standards. Mr. J. Herr (Manager, Pipe Technology Dept., Johns-Manville Corp.) summarized the data and conclusions of tests conducted at J-M. A copy of the summary of J-M's Research Report No. E425-1074 is attached to this memorandum. It was concluded in the report that, within the scope of the tests, only pH was found to be of any significance in ascertaining attack on the a/c pipe. In a subsequent discussion of the J-M data, the test-procedures were severely criticized and the validity of the data and con clusions was questioned. Experimental data were also presented by Mr. Fred Hawkins (Certain Teed Corp.) on investigations conducted by Keasbey and Mattison Co. in 1961 on the resistance of a/c pipe to soft waters. It was concluded from this study that the stability of a/c pipe was very dependent upon the hardness of the water. The pH of the water, within the range investigated (6.4 to 8.3), or any other factor had little or no effect on the attack of the pipe. It was agreed that additional experimental work is required to study the release of fiber from a/c pipe. The Association would then be in a position to recommend changes to the AWWA on the criteria of waters suitable for transport in a/c pipes. The alternative, -it was believed, would be eventual much stricter limitations by the EPA-. Coating of the pipe to prevent erosion and fiber release was considered to be an unacceptable solution (last resort), mainly because of bad publicity. It would imply that there is some thin wrong with a/c pipe already installed and it would scare the public. It would also add to the production cost and make a/c nipe less competitive. All member companies of AACPP were urged to participate in addi tional studies aimed at ascertaining which attributes of the water are responsible for leaching of a/c pipe or, conversely, the deposition of a natural protective coating. A task force comprising of F. TTawVing (chairman) and J. Herr S** was set up to direct the Association4 s tuture efforts. ~=l`her--~ task force will write up standardized test procedure for aggres sive waters on a/c pipe and will ask each member company to par ticipate in the study. It is estimated that about 4 weeks will I ASARCO ALV 0000920 Mr. E. Martinez -4- be required to write up the procedures, suggested variables to be investigated, etc. The member companies will then be contacted by the Association and will be ashed (voluntarily) to. undertake specific portions of the investigation. In discussing the conclusions of the meeting privately with Mr. Lee Taylor (V.P. of Marketing and Sales, Capco), Mr. Taylor expressed the opinion that Asarco should definitely participate in the Association's suggested investigations because of its im plications on the future of the a/c pipe industry. Mr. Taylor, however, disagreed with the conclusion that coated pipe should not be produced. He suggested that coated pipe should be pro duced and installed in locations where the water is aggressive, thereby expanding the a/c pipe market. I!e also suggested that the technology should be developed to coat the pipe after forming, i.e. before curing and autoclaving. This would retain more moisture in the pipe during curing, thereby enhancing the strength. This, in turn, may permit a reduction of the fiber content of the furnish and the net result may be a cost saving. I VP/cdh cc: A.E.Albrethsen M.El Tawil V.ICudryk C.E.Stiefken V. Puskar Vj I ASARCO ALV 0000921