ARCHIVED REPORTS XR0008623 - Laserfiche WebLink

Home Browse Search

SAl11PLE IDENTIFICATION AND CELAIN-OF-CUSTODY PROCEDURES demonstrates the effectiveness of m-field cleaning procedures to prevent cross- SOP-4 contamination. Sample identification and cham-of-custody procedures entre sample integrity, and do..ument sample possession from the time of collection to its ultimate To minutuze the potential for cross-contammalson between wells, all well disposal Each sample contamer submitted for analysts is labeled to identify the development and water sampling equipment not dedicated to a well is either ob number, date, time of sample collection, a sample number unique to the steam cleaned or properly washed between use As a second precautionary ample any name(s) of on-site personnel and any other pertinent Feld measure, wells are sampled in order of lowest to highest concentrations as observations also recorded on the field excavation or boring log established by available previous analytical data. Chain-of-custody forts am used to record possession of the sample from time of In the event the water samples cannot be submitted to the analytical laboratory collection to its amval at the laboratory During shipment, the person with on the same day they are collected (e g., due to weekends or holidays), the urstodv of the samples will relinquish them to the next person by signing the samples are temporarily stored until the first opportunity for submittal either on -.ham-of-custody form(s) and noting the date and time The sample-control ice in a cooler,such as when in the field,or in a refrigerator officer at the laboratory will verify sample integrity,correct preservation,confirm ,oliecuon in the proper contamer(sl and ensure adequate volume for analysis MEASURING LIQUID LEVELS USING WATER LEVEL INDICATOR OR INTERFACE PROBE If these conditions are met,the samples will be assigned unique laboratory log SOP-12 numbers for idenuftesuon throughout analysis and reporting The log numbers Field equipment used for hquid-level gauging typically includes the measuring will be recorded on the cham-of-custody forma and in the legally-required log probe(water level or interface)and a clean product batler(s) The field kit also hook maintained in the laboratory The sample description,date received,client's includes cleaning supplies(buckets,TSP,spray bottles,and detontzed water)to name and any other relevant information will also be recorded be used in cleaning the equipment between wells [A HORATORY ANALY'T'ICAL QUALITY ASSURANCE AND CONTROL Prior to measurement, the probe up is lowered into the well until it touches SOP-5 bottom Using the previously established top-of-casmg or top-of-box (i e In addition to routine instrument calibration, replicates, spikes, blanks, spiked wellhead vault)point,the probe cord(or halyard)is marked and a measuring tape blanks and certified reference matenals are routinely analyzed at method-specific (graduated in hundredths of a foot)is used to determine the distance between the frequencies to monitor precision and bras Additional components of the probe end and the marking on the cord This measurement is then recorded on hhoralory Quality Assurance/Quality Control program include the liquid-level data sheet as the"Measured Total Depth" of the well I Participation in state and federal laboratory accrednation/certtfication When necessary in using the mterfsce probe to measure liquid levels,the probe programs, is first electrically grounded to either the metal stove pipe or another metal object 2 Parucipauon in both U S EPA Performance Evaluation studies(WS and nearby When no ground is available, reproducible measurements can be WP studies)and inter-laboratory performance evaluation programs, obtained by cltppmg the ground lead to the handle of the interface probe case 3 Standard operating procedures describing routine and periodic msbument maintenance, The probe tip is then lowered into the well and submerged in the groundwater 4 'Outof-Control"lCorrecuve Action documentation procedures,and, An oscillating(beeping)tone indicates the probe is in water The probe is slowly Multi-level review of raw data and client reports raised until either the oscillating tone ceases or becomes a steady tone In either case,this is the depth-tri-water(DTW)indicator and the DTW measurement is GROUNDWATER PURGING AND SAMPLING made accordmgly The steady tone indicates floating hydrocarbons In this case SOP-7 the probe is slowly raised until the steady tone ceases This is the depth-to- Prior to water sampling,each well is purged by evacuating a mtmmum of three product(DTP)indicator and the measurement of DTP is recorded A corrected WLtted well-casing volumes of groundwater When requwed, putgmg will depth to groundwater to account for floating hydrocarbons can be calculated by continue until either the discharge watertemperanrre,conductivity,or pH stabilize using the following formula to within 100/9 of previously measured values, and a maximum of ten wetted rasing volumes of groundwater have been recovered,or the well is bailed dry CDTW- DTW-(SP G x LHT) When practical,the groundwater sample should be collected when the water level CDTW =Corrected depth to groundwater in the well recovers to at least 80 percent of its static level Field measurements, DTW =Measured depth to groundwater observations and procedures are noted SP G=Specific gravity unweathered gasoline=0 75,diesel =0 80 LHT=Measured liquid hydrocarbon thickness The sampling equipment consists of a clean bailer,or stainless steel bladder pump with a Teflon"bladder If the sampling system is dedicated to the well,then the The corresponding groundwater elevation is the difference between a previously bailer is usually "Teflon," but the bladder pump may be PVC with a determined well reference elevation and either the depth to groundwater or the polypropylene bladder Sample container type,preservation,and volume depends corrected depth to groundwater on the intended analyses The process of lowering and raising the probe must be repeated several times to The groundwater sample is decanted into each VOA vial in such a manner that ensure accurate measurements The DTW and DTP measurements are recorded there is no meniscus at the top of the vial A cap is quickly secured to the top on the liquid-level data sheet- When floating product is indicated by the probe's of the vial The vial is then inverted and gently tapped to see if air bubbles arc response,a product bailer is lowered partially through the product-water interface present If none are present,the vial is labeled and refrigerated for delivery, to confirm the product on the water surface,and as further indication of product under strict chain-of-custody, to the analyucal laboratory Labei information thickness,particularly in cases where the product layer is quite thin Either this should include a unique sample identification number,fob identification number, measurement or the difference between DTW and DTP is recorded on the data date time,and the sampler's intuals sheet as"product thickness" For quality control purposes,a duplicate water sample may be collected from a In order to avoid cross-contammauon of wells during the Itquid-level well When required,a trip blank is prepared at the laboratory and placed in the measurement process,wells are measured in the order of"clean"to"dirty"(where transport cooler It is labeled similar to the well samples,remains in the cooler such information is available) In addition,all measurement equipment is cleaned .019uring trarisporl,and is analyzed by the laboratory along with the groundwater with TSP or suntlar solution and thoroughly rinsed with deionized water before Ales In addition.a field blank may be prepared in the field when sampling use,between measurements in respective wells,and at the completion ofthe day's ,quipment is not dedicated The field blank is prepared after a pump or bailer activities has been either steam cleaned or properly washed,prior to use in the next well, and is analyzed along with the other samples The field blank analysts Fugro OMR SOPS 4 5 7 t?J7gW