Document 2qK8mgyzzJ6K46jgdvaGqpJML

Afi. c UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION VI 1201 F.I.M trlKLCT DALt.AS. 1I.XA% /h270 ; October 30., 1900 . Marilyn Ri fe ' 101 Arcadia Place,, 310 r San Antonio, TX 78209 ... `* Rear Ms. Rife: ' Thank you for your letter of October. 2,. 1980. We share your concern with , reports of asbestos in drinking water. The Envirormental Protection Agency (EPA),, Region 6 office, has been in commu nication with the Texas Deparbnent of Health, the Edwards Underground Water District, and the City Water Board of San Antonio since reports of asbestos in San Antonio's water began. We have also consulted with our own EPA re- ** search and health effects laboratories and our technical support division. Based upon our findings, we do'hbt'believe the citizens of San" An td'nio'`are"/ ' subject to any measurable health, risk frail asbestos in their drinking water.; There are two possible sources of asbestos in San Antonio's water. These are from naturally occurring sources in the ground water,, and asbestos fibers from the asbestos-cement water pipe. \ In our communications, the Edwards Underground Water District has-confinned that portions of the Edwards Aquifer have asbestos-hearing rock formations which yield small amounts of asbestos to the ground water. Present scientif ic infonnation does not indicate that these levels represent a significant health risk. However, water "samples of the source ground water in the San Antonio municipal water supply do tipt indicate the presence of asbestos. f The second possible source is asbestos-cement pipe. Asbestos-cement pipe - has been widely used throughout the.Uni ted States for over 40 years. Its advantages are high strength, relative low cost compared to other materials,, and resistance to soil corrosion. This high strength results from asbestos fillers mixed in the cement which act as reinforcing agents in the hardened .concrete. Despite extensive research, no satisfactory substitute for the . asbestos in the compound has been discovered. When asbestos-cement pipe is used to transmit highly corrosive waters, .deterioration of the concrete can occur, releasing some of the asbestos - fibers. Asbestos-cement pipe has been the subject of extensive studies, and * these indicate that noncorrosive source waters such as found in San Antonio, do not attack asbestos-cement pipe, and no fibers are released. CAPCO JEN 0010490 .mm - H.irted teststo determine ff a commonly used method \ .-.and tapping ffoo/r new connections released asbestos particles into f Sfvf*r^tg^pSCarnVd`;>thSeammpelethsodtakoefnddruilrliinnggthanisd teapsptiinng choansfibneneendchthaennreel l^coc5n^f :.B^sVare prevented from getting intiV water Subseouent t?f ^eS& .-;P^^etectable levels of asbestos in the water. quent tests show . of th' e. ack'nowledge dV..h. ealth pi.rvo-blems- related to. a sb^-^ 7 V , : and/or ingested by workers in occupational exposure it ?e?hd]ed people to extend this concern to other exposures IpA^nrt ??tUrill fr community have felt, that extensively ^JustmSto"l^ninelf^ere ` a3" ^ ----------- ^ f^lSK Uw |1UU I I U IIVUI v " gastroi ntest! naT cancer,- incidence wi ing/water^ ;.. ; I. appreciate your-"concern for public health protection. Please be assured that we will continue to stay in touch with the agencies involved in main taining the quality of water in the San Antonio area,,, and we will advise them of the continuing research findings both in our own agency and the scientific community at large. Mac A.- Weaver... Acting Chief. Water Supply branch (6AWS) cc: C. K. Foster, P.E. G. H. Schorwitz, Jr., P.E. ' Thomas P. Fox *t_ Robert P. Van Dyke t/ U.S. Environmental Protection rtyc?ncy ' .' Washington, D.C. 20*160 Water Supply Staff CAPCO JEN 0010491