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ST8805-CS 890609 The City With A Beautiful Future June 9, 1989 P.O. Box 478 , ~'- Coppel,, T~~. ~ 214-462-~ ..... ~ Mr. Marty :tus NDRC Headqu ~ers, Inc. 3553 Miller '.ye Garland, 75042 RE: PARKWAY 5EVARD WATER SAMPLES - COPPELL, TEXAS Dear Mr. As per our t, conversation on June clarification o three bacteriological samples, 9831, reported by Laboratories, Inc. 2, 1989, requesting Lab No. 9829-9830 and My question was regarding your reporting procedures indicating a detection limit of 3 col/100 ml or less as being a passing water sample, accepted by the Texas Department of Health. I am sending you copies of information published by the Texas Department of Health and Texas A&M University, which indicates a passing water sample analysis will indicated "no cloriform organisms found". Please confirm, in writing, that the less Texas Department of health regulations above. than 3 col/100 ml meets the for each of the samples listed Should you have any questions, please contact me at (214)'462-0022. Sincerely, Larry D~v~s Constr~ction ~nspector LD/lsg xc: Murray Construction L.H. Lacy Company Howard Pafford Jerry Parche, P.E. Russell R. Doyle, P.E. PRKW/WTR BACTERIOLOGICAL QUALITY OF WATER TOPICS DISCUSSED: III. I. Test for coliform group A. Definition of coliform group B. Media and technique of presumptive test C. Media and technique of confirmed test D. Media and technique of completed test E. Membrane filter techniques II. Safe Drinking Water Standards A. Number of samples B. Quality Most Probable Number SUMMARY: (1) (2) (3) (4) (5) (6) (7) The coliform group is defined as being all of the aerobic and facultative anaerobic Gram-negative, non-spore-forming short rod bacilli which ferment lactose with gas formation within 48 hours at 35 degrees centigrade. Lactose broth or Lauryl Tryptose broth may be used in the pre- sumptive test. Brilliant Green Lactose Bile Broth or Eosin Methylene Agar Plates may be used in the confirmed test. Completed test may be applied to Brilliant Green Lactose Bile Broth tubes showing gas or to typical or atypical colonies found on Eosin Methylene Blue or Endo Agar plates. The Membrane Filter method gave faster results than the fermen- tation tuu~ method, The number of samples collected per month to meet Safe Drinking Water Standards is dependent upon population. Bacteriological qualities necessary to meet Safe Drinking Water Standards are as follows using the fermentative tube method: a. Of all the l0 ml portions examined per month not more than 10% shall show the presence of coliform organisms. b. Three or more of the 5 ml portions of a single sample may show the presence of coliform organisms provided it does not occur in consecutive samples nor in more than 5% of the samples per month if over 20 samples are examined or in more than one sample if less than 20 samples have been examined. Provided further that when three or more of the 5 ml portions show the presence of coliform organisms, daily samples shall be examined until two consecutive samples show the water to be good quality. -1- TE),AS DEPARTMENT OF HEALTH LABORATORIES WATER BACTERIOLOGY ANALYSIS Name of Water System County lloint of Collection S~nd report to: NAME Collected by Date {Mo., Day, Yr.) [,,rm No. G-19 STREET CITY Water System Identification Number TEXAS (Zip Time AM/PM TYPE OF SYSTEM: CI Public ODeiry C]lndividual OBottled Water I-1 School E]Swimmmg Pool Ownership or other information: n Alternale Test SAMPLE IS: (Public Systems Only) [3Oistribution l-IRaw C~Check ClConstruction C]St3ecial WATER SOURCE OR iver C) Lake r-lWall Well depth Chlorine residua! E']Prelimmary Report / OFinal Rt~port J' M-'~PN Conf, med'Test. MPN Completed Test MF Coliform Count Ipresumptive} MF Coliform Count (verified}__ Coliform Orgamsms Lab. Ident. No. and Name [3Found [-]Not Found /100 mi. Unsatisfactory E3F3rm ~ncomplete. (See en¢*rcled item.} [~mple too old. Sample not received within 30 hours of collection. ~] Excessive chlorine present *fl s~mole. OBroken ,n shipment ~Date discrepancy. ~uantttV too gre~t t~ permit agitation. ~Ouantity msuffic,ent for armlvs*s, (100 mi. mimmum) ~Bottle nol I)row~d I)y lh~5 lat~oralnry. ~Heavy nor~-~olif~rnl ~ctell.* ~lt pr~ent, possibly ob~uring and comprom~ling tilt. fi'lease ch~ck AIl{,mate T~i un~ Ownership and Other Information when resubmitting.) ~Only one sample ~r time and point of collection required. Other Approved by W.tter of satisfactory bacteriological quality should be free from Coliform Organisms. 17 Since it is impo.~sible to trace the origin of fecal pollution to deter- mine whether it came from animal or man, the further to determine whether tl~. animal or man was sick or well, it is necessary and safer to keep the water free from all ft, cal pollution. To be sure that this has been accomplished samples of the water should be submitted periodically to a laboratory for bacteriological analysis. When the report of this analysis indicates "no coliform organisms found," the water is considered "safe." If the laboratory reports "coliform organisms present," it is evidence of fecal pollution and the water is considered "unsafe" and unfit for human consump t ion. Number of Samples to be Collected. The minimum number of samples to be collected from a public water supply and submitted for examination shall be in accordance with the following table. Poi~_ulat on Served 0 to 1,000 1 001 to 3,300 3 301 to 4,100 4 101 to 4,900 4 901 to 5,800 5 801 to 6,700 6 701 to 7,600 7 601 to 8,500 8 501 to 9,400 9401 to 10,300 10,301 to 11,100 11,101 to 12,000 12,001 to 12,900 12,901 to [3,700 1'~,701 to 14,600 14,601 to 15,500 i5,501 to 16,300 16,301 to 17,200 17,201 to 18,100 18,101 to 18,900 18,901 to 19,800 19,801 to 20,700 20,701 to 21,500 21,501 to 22,300 22,301 to 23,200 23,201 to 24,000 24,001 to 24,900 24,901 to 25,000 25,001 to 28,000 28,001 to 33,000 33,001 to 37,000 37,001 to 41,000 ~!,001 to 46,000 Minimum Number of Samples Per Month 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 3O 35 4O 45