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1 <br /> (but not touching) the bottom of the well Small volumes of purgewater are often removed by hand <br /> balling with a disposable bailer <br /> PARAMETER STABILIZATION <br /> ' Well purging completion standards include minimum purge volumes, but additionally require <br /> stabilization of specific groundwater parameters prior to sample collection Typical groundwater <br /> parameters used to measure stability are electrical conductivity, pH, and temperature Instrument <br /> ' readings are obtained at regular intervals during the evacuation process (no less than once per case <br /> volume) <br /> ' Stabilization standards for routine quarterly monitoring of fuel sites include the following Temperature <br /> is considered to have stabilized when successive readings do not fluctuate more than {/- 1 degree <br /> Celsius Electrical conductivity is considered stable when successive readings are within 10% pH is <br /> ' considered to be stable when successive readings remain constant or vary no more than 0 2 of a pH unit <br /> DEWATERED WELLS <br /> ' Normal evacuation removes no less than three case volumes of water from the well However, less water <br /> may be removed in cases where the well dewaters and does not recharge <br /> ' Wells known to dewater are evacuated as early as possible during each site visit in order to allow for the <br /> greatest amount of recovering Any well that does not recharge to 80% of its original volume will be <br /> ' sampled prior to the departure of our personnel from the site in order to eliminate the need of a return <br /> visit <br /> In jurisdictions where a certain percentage of recovery is included in the local completion standard, our <br /> personnel follow the regulatory expectation <br /> ' PURGEWATER CONTAINMENT <br /> All non-hazardous purgewater evacuated from each groundwater monitoring well is captured and <br /> ' contained in on-board storage tanks on the Sampling Vehicle and/or special water hauling trailers <br /> Effluent from the decontamination of reusable apparatus (sounders, electric pumps and hoses etc), <br /> consisting of groundwater combined with dcionized water and non-phosphate soap, is also captured and <br /> ' pumped into effluent tanks <br /> Non hazardous purgewater is transported under standard Bill of Lading documentation to a Blaine Tech <br /> Services, Inc facility before being transported to an Exxon approved disposal facility (e g Romic <br /> Environmental Technologies Corporation in East Palo Alto,California) <br /> ' SAMPLE COLLECTION DEVICES <br /> All samples are collected using a disposable bailer <br /> SAMPLE CONTAINERS <br /> Sample material is decanted directly from the sampling bailer into sample containers provided by the <br /> laboratory,which will analyze the samples The transfer of sample material from the bailer to the sample <br /> container conforms to specifications contained In the USEPA T E G D The type of sample container, <br /> 1 <br /> Lrp005 865 <br />