SAMPLE IDENTIFICATION AND CHAIN-OF-CFISTODY PRCKZDURES demonstrates the effectiveness of m-field cleaning procedures to prevent crosc-
<br /> SOP4 contarrimation
<br /> Sample identification and chain-of-custody procedures ensure sample integrity
<br /> and document sample possession from the time of collection to its ultunate To mmimat the potential for cross-comammation between wells, all well
<br /> disposal Each sample container submitted for anahrsur n labeled to identify the development and water sampling equipment not dedicated to a well is either
<br /> *b number, date, time of sample collection, a sample number unique to the steam cleaned or properly washed between use As a second precautionary
<br /> ample any name(s) of on-site personnel and any other pertinent field measure, wells are sampled m order of lowest to highest concentrations as
<br /> observations also recorded on the field excavation or boring log. established by available previous analytical data.
<br /> Cham-of-custody forts are used to record possession of the sample from time of In the event the water samples cannot be submitted to the analytical laboratory
<br /> collection to its arrival at the laboratory During shipment, the person with on the same day they are collected (e g, due to weekends or holidays) the
<br /> custodv of the samples will relinquish them to the next person by signing the samples are temporarily stored until the fust opportunity for submetal either on
<br /> chain-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
<br /> ofliccr at the laboratory will verify sample integrity cormct preservation,confum
<br /> 6ollection in the proper container(s),and ensure adequate volume for analysis MEASURING LIQUID LEVELS USING WATER LEVEL INDICATOR OR
<br /> INTERFACE PROBE
<br /> If these conditions are met,the samples will be assigned unique laboratory log SOP-12
<br /> numbers for identification throughout analysis and reporting The log numbers Field equipment used for liquid-level gauging typically includes the measuring
<br /> will be recorded on the chain-of-custody forms and in the legally-required log probe(water level or interface)and a clean product bailer(s) The field kit also
<br /> book maintained in the htboratory The sample description,date received,client's includes cleaning supplies(buckets,TSP,spray bottles,and deronized water)-Lo
<br /> name,and any other relevant information will also be recorded be used in cleaning the equipment between wells
<br /> LABORATORY ANALYTICAL QUALITY ASSURANCE AND CONTROL Prior to measurement, the probe tip is lowered into the well until it touches
<br /> SOP-5 bottom Using the previously established tap-of-casing or top-of-box (a e
<br /> In addition to routine instrument calibration, replicates, spikes, blanks, spiked wellhead vault)point,the probe cord(or halyard)is marked and a measuring tape
<br /> blanks,and certified reference materials are routinely analyzed at method-specific (graduated in hundredths of a foot)is used to determine the distance between the
<br /> frequencies to monitor precision and bias Additional components of the probe end and the marling on the cord This measurement is then recorded nn
<br /> laboratory Quality Assurance/Quality Control program include the liquid-level data sheet as the "Measured Total Depth"of the-Atli
<br /> 1 Panisrpauon to state and federal laboratory accredrtation/certification When necessary tit using the interface probe to measure liquid levels the probe
<br /> programs, is first electncally grounded to either the metal stove pipe or another metal object
<br /> 2 Participation in both U S EPA Performance Evaluation studies (WS and nearb) When no ground is available, reproducible measurements can be
<br /> WP studies)and inter-laboratory performance evaluation programs, obtained by clipping the ground lead to the handle of the interface probe case
<br /> 3 Standard operating procedures describing routine and periodic instrument
<br /> maintenance, The probe hp is then lowered into the well and submerged in the groundwater
<br /> 4 Out-of=Control"/Corrective Action documentation procedures and, An oscillating(beeping)tone indicates the probe is in water The probe is slowly
<br /> Multi-level review of raw data and client reports raised until either the oscillating tone ceases or becomes a steady tone In erther
<br /> case,this is the depth-to-water(DTW)indicator and the DTW measurement is
<br /> GROUNDWATER PURGING AND SAMPLING made accordingly The steady tone indicates floating hydrocarbons In this case
<br /> SOP-7 the probe is slowly raised until the steady tone ceases This is the depth-to
<br /> Prior to water sampling,each well is purged by evacuating a minimum of three product(DTP)indicator and the measurement of DTP is recorded A.corrected
<br /> wetted well-casing volumes of groundwater When required, purging will depth to groundwater to account for floating hydrocarbons can be calculated hx
<br /> uitninue until either the discharge water temperature conductivity,orpH stabilize using the following formula
<br /> io within 10% of previously measured values, and a maximum of ten wetted
<br /> using volumes of groundwater have been recovered,or the well is bailed dry CDTW=DTW-(SP G x LHT)
<br /> When practical,the groundwater sample should be collected when the water level CDTW=Corrected depth to groundwater
<br /> in the well recovers to at least 80 percent of its static level Field measurements, DTW R Measured depth to groundwater
<br /> observations and procedures are noted SP G=Specific gravity unweathered gasoline=0 75,diesel -0 80
<br /> LHT=Measured liquid hydrocarbon thickness
<br /> The sampling equipment consists of a dean bailer,or stainless steel bladder pump
<br /> 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
<br /> bailer is usually "Teflon," but the bladder pump may be PVC with a detetrnened well reference elevation and either the depth to groundwater or the
<br /> polvpropylenc bladder Sample contamertype,preservation,and volume depends corrected depth to groundwater
<br /> on the intended analvses
<br /> The process of iowenng and raising the probe must be repeated several times to
<br /> The groundwater sample is decanted into each VOA vial in such a manner that ensure accurate measurements The DTW and DTP measurements are recorded
<br /> 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 probes
<br /> of the vial The vial is then inverted and gently tapped to see if air bubbles are response,a product bailer is lowered partially through the product-water interface
<br /> 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
<br /> under strict chain-of-custody, to the analytical laboratory Label information thickness particularly in cases where the product laver is quite thtn Either this
<br /> should include a unique sample identification number,lob identification number, measurement or the difference between DTW and DTP is recorded on the data
<br /> date time and the samplers mitrals sheet as"product thickness"
<br /> 1•0r quality control purposes,a duplicate water sample may be collected from a In order to avoid cross-contamination of welts during the liquid-level
<br /> well When required a trip blank is prepared at the laboratory and plaited in the measum tent process,wells are measured in the order of"clean"to"duty"(where
<br /> 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
<br /> 0unng transport,and is analyzed by the laboratory along with the groundwater with TSP or similar solution and thoroughly rinsed with deronued water before
<br /> 'amples In addition,a field blank may be prepared in the field when sampling use,between measurements in respective wells,and at the completion of the day s
<br /> equipment is not dedicated The field blank is prepared after a pump or bailer activities
<br /> has been either steam cleaned or properly washed,pnor to use in the next well,
<br /> and is analvzed along with the other samples The field blank analysts
<br /> Fugro
<br /> QMR SOPS 4 5 7 12JI994
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