ARCHIVED REPORTS XR0001845 - Laserfiche WebLink

Home Browse Search

GROUNDWATER MONITORING,SAMPLING, AND SAMPLE MANAGEMENT PROCEDURES L Notifications Prior to performing any field work,the client, regulatory agency,and property owner/manager with jurisdiction over the subject site are notified Notifications are made a minimum of 48 hours prior to sampling, or as required by the client or regulator 2. Water Level Measurements Prior to performing purge or no-purge sampling, water level measurements are collected according to the following procedures • All wells are checked for phase-separated hydrocarbons with an acrylic bailer or oil/water interface meter • To avoid cross contamination,water levels are measured starting with the historically "cleanest" wells and proceeding to the historically "dirtiest " • Water levels within each well are measured to an accuracy of =E0 01 foot using an electric measuring device and are referenced to the surveyed datum(well cover or top of casing) When measuring to top of casing, measurements are made to the notched (or otherwise marked)point on casing If no marking is visible,the measurement is made to the northern side of the casing • If possible, all wells are gauged within a short time interval on the same day to obtain accurate measurements of the potentiometric surface • All measurements are reproduced to assure validity, and measuring equipment is decontaminated between wells 3. Phase Separated Hydrocarbon If phase-separated hydrocarbon(PSH) is encountered, its thickness in the well ai)d the depth to the interface between the PSH and the water in the well are invasured using one or bpath of the following methods • an electronic oil-water interface meter is used to measure the depths to the top of the PSH and to the top of the water, and/or • an electronic water level meter is used to measure the depth to the top of the water and a clear bailer is used to measure the PSH thickness M=L D1EnvironmentW\PaznzarTexaco\Reporls\SAR1203 wpd