Loading...
sr-072380INFORMATION Santa Monica, California July 23, 1980 To From Subject Mayor and City Council City Staff Progress Report on Monitoring of TCE in Vdater System Introduction This report provides information relating to the monitoring of TCE in the water system for the period from May 1980 until the present time. This report will also provide information on certain actions that the staff has taken to reduce the amount of TCE in the system. Background On April l4, the City Council took action to request the staff to take a number of measures to control and reduce the levels of TCE in the water system. (Item 11-C). Those items included: engaging a consultant to monitor industries using TCE, appropriation of $50,000 to engage consultants to take borings and try to discover the source of the contamination, and to re-open well Number 3 and to perform monitoring to determine the levels of TCE at various points in the system. Progress which has been made to date includes action on all three aspects of the approved course of action. Dr. Herbert Conrad of Ecological Systems, Inc., Santa Plonica, was engaged to monitor the industries using TCE and is approximately 60% completed. It is anticipated that it will be completed and a report will be ready for presentation to Council within the next 60 days. The engaging of a consultant to try to discover the sources of the contamin- ation is ready to be submitted to the Council for consultant selection in To: Mayor and City Council -2- July 23, 1980 August. An RFP was distributed to a number of cons u7tants and proposals have been received and evaluated. The staff is ready to recommend a consultant, together with a proposed detailed course of action. Progress on the monitoring and testing of the water at various points in the system has been accomplished in accordance with the testing schedule recommended by the State Health Department and approved by the City Council. This schedule included monitoring (testing) daily .for the first two weeks, and weekly for the following two weeks, bi-weekly for three months, monthly for three months, and quarterly thereafter. The detailed results of the testing are attached to this report for reference. Also attached are graphs showing how the TCE levels varied in the water distributed to the customers. The TCE levels in the water distributed to the customers have varied from 0.6 to 4.7 parts per million during the period from May until the present time. The TCE levels were generally below 2.0 during the month of May, but increased to a maximum of 4.7 in the system during the month of June. Because the levels appeared to be approaching 5.0, the limit suggested by the City Council, the staff took immediate steps in June to introduce increased aeration at the Arcadia Treatment Plant. The amount of aeration eras approximately doubled by the installation of a dual blower and piping system. Since this installation, the TCE levels have been significantly reduced and the latest test, dated July 17, 1980 for water sampled on July 2, 1980, shows that the TCE levels in the system are 0.6 parts per billion. Because of the fact that levels of TCE have been controlled and are presently significantly less .than the Maximum Concentration Limit (MCL), the aeration and blending operations appear to be successful and appear to be meeting the To: Mayor and City Council -3- policy guidelines established on April 14, 1980. July 23, 1980 The staff proposes to continue the monitoring program as approved by the City Council in April and to take action to continue to control the TCE levels by using one or more of the following methods: 1. If TCE levels begin to approach the MCL, increased aeration will be used. 2. Limit the number of hours per day of operation of Wells Number 2 and 3. Prepared by: Stan Scholl Jack Hoagland Attachments: Test Results -- July 17, 1980 Memo Summarizing Test Results -- July 10, 1980 Memo Summarizing Test Results -- May 28, 1980 Graph showing TCE levels in wells versus levels to consumers Graph showing total trihalomethanes in each pressure zone T Prepared FOr city of Sant.; ffenica 12,2 S. Mundy iar^, !_os Y'lnyeies, Cri 9L'(:2S Attn: Jack C-!ea~}and Date Job No. >L P.O. No. Date Received 1-3i?.37 Jury ~, 7S3C; Description of Samples 17605 Fabrica Way Cerritos, California 90701 2131921-9831 .'714/523-9200 Tf-:reE ;eater s~rrples (?n c?upiicate) labeled 529, rr34, anc' Sat. TF.e z.Eove sa Y:p les +.+Jere extracted into iscectane ar.d analyzed for ir1- chlcroathylene (TC~} e^, a gas chror. atograph equiFped v~ith an electron capture ^etecior. Tha results are listed hefovr: Sample TCE()IC~fL} F29 ;~2 ~,G ~j~G _ .~[ X37 - E • ~ ~ r9 : '-~ 5 T We would appreciate a telephone call it you have any questions regarding this report. Page 1 of ~ pages. I certify that this report truly represents the findings of work performed by me, or under my direct supervision. .~-> ,~ c~ r:rac clezt Staff C'r~Ft•ist Reviewed & Approved. G. J. h:crthirg:cn, Ft-i.u. TecFxtical uirecwr This report pertains only to the samples investfgatetl and does not necessarily apply to other apparently itlentical or similar materials. THIS report is submitted /or the exclusive use of the client to whom it is addressed. Any reproduction of this report or use of this Laboratory's name for atlvertising or publicity purposes without written authorization is prohiDitetl. ,~ DATE: July 10, 1980 T0: Ed Lash FRODi: J: Hoagland CITY OF SANTA MONICA SUBJECT: TCE MONITORING PROGRAM ANALYSIS REPORT S,1[dL # DATE LOCATION TCE (oob) 419 5-21 14th & Olympic Sampler 1.8 4"22 5-21 Arcadia Reservoir Effluent 1.7 423 5-21 Santa Monica Well #2 6.9 424 5-21 Santa Monica 4Je11 #3 14.7 425 5-21 Salt Water Line @ Arcadia 1.6 441 5-28 Santa Monica 4Jell #2 6.6 442 5-28 Santa Monica [Jell #3 23.3 443 5-28 Main St. Sampler 3.7 444 5-28 Arcadia Reservoir Effluent 3.2 478 6-4 14th & Olympic Sampler 4.7 479 6-4 Santa Monica [Jell #2 6.4 480 6-4 Santa Monica Well #3 31.0 481 6-4 Arcadia Reservoir Effluent 4.6 521 6-11 Main Street Sampler - 3.5 524 6-11 Santa Monica Well #2 7.8 525 6-11 -Santa Monica 4Je11 #3 29.0 526 6-11 Arcadia Reservoir Effluent 3.8 563 6-18 Santa F4onica 41e7 i #3 33.0 564 6-78 14th & Olympic Sampler 3.1 566 6-18 Santa Monica Well #5 N.D. (< 0.1) Discussion: Santa Monica lJell #3 shows a relatively sharp increase in TCE levels'fron} the 7.3 ppb values during the first two weeks of operation to the apparent "steady-state" level of approximately 30. parts per billion. Santa Monica #2 shows stability at approximately 7.0 ppb. CITY OF SAP~iTA MC3NiCA ~~~~~ ~ ~~ DATE:May 28, 1980 TO: Mr. Ed Lash; Enterprises Manager FROIS: Jack Hoagland, Gdater Chemist ` SUBJECT: TCE :lonitor.ing Program: First Twa Gdee~s Report Following are the results of the TCE l>oni_toring program-for the days May 7, 19$0, to clay 20, 1980, iriclusi_t:u. ThQsA samples were sampled by the Water CheLaist and analysed by thg State Departme~it of Health Services, P,esults are in parts per billion Trickiorc~~c-t,iyler~e Sivl~~2 is Santa Monica [dell '=2 Srl~r3 is Santa *lonica We 11 ~3 Arc, Res. is Arcadia Reservoir EffluenC to tlc- 2`~0 foct ~,orie and represents the ma_~~um amount of TCE that a consumer might receive,. DATA.' Ski.=2 SM~~3 " AF.C.RES 5-7-80 7.8 6.5 0.1.8 5-8 7.0 7.6 1,6 5-9 7.5 6.5 1,7 5-10 7.5 7.5 1,.5 5-11 7.1 8.2 1.8 5-12 7.3 8,3 ~:,.7 - 5-13 7.1 8,4 1,6 5-14 7.9 8,7. 1.8 5-15 7,6 7.6 1,7 5-l0' 7.3 8.1 1.7 5-17 7:4 7.7 1,7 5-18 7,6 8,9 1.7 5-i9 7.2 10.0 1,8 5-20 6.0 7.6 0,80 These analyses v,ere done only by the State and we have no cross check of their accuracy. _ Currently wee'.{Iy samples are being analysed by an outside LaYi,. ~oith results expected by Jnne 2, 1980, RECEIVED BY 4 CONSUMERS IN THE 250 ff. 3 PRESSURE ZONE 2 0 ~ 5-7 - 5-20 5-28 6•I 6-4 -'6-II ' 6-18 DATE 7-I 7.2 COMPARISON OF TTNM AND TCE CONCENTRATIONS IN SANTA MONICA PRESSURE ZONES Parts per billion TCE = Trichloroethylene TTHM = Total Trihalomethanes * from April 17, 1980 23/80 "250 foot * 350 foot * 500 foot zone zone zone