Laserfiche WebLink
1 <br /> APPENDIX 1 <br /> GROUNDWATER MONITORING,SAMPLING, <br /> AND SAMPLE HANDING PROTOCOL <br /> 1. Notifications <br /> Prior to performing any field work,the client, regulatory agency, and property <br /> owner/manager withjunsdiction over the subject site are notified Notifications are made a <br /> mimmum of 48 hours prior to sampling, or as required by the client or regulator. <br /> 2. Water Level Measurements <br /> Prior to performing purge or no-purge sampling, water level measurements are collected <br /> according to the following procedures <br /> • All wells are checked for phase-separated hydrocarbons with an acrylic bailer or <br /> oil/water interface meter. <br /> • To avoid cross contamination, water levels are measured starting with the <br /> historically "cleanest"wells and proceeding to the historically "dirtiest " <br /> • Water levels within each well are measured to an accuracy of ±0 01 foot using an <br /> electric measuring device and are referenced to the surveyed datum(well cover or <br /> top of casing) When measuring to top of casing„ measurements are made to the <br /> notched(or otherwise marked)point on casing If no marking is visible,the <br /> lie measurement is made to the northern side of the casing <br /> • If possible,all wells are gauged within a short time interval on the same day to <br /> obtain accurate measurements of the potentiometric surface <br /> I • All measurements are reproduced to assure validity, and measuring equipment is <br /> decontaminated between wells <br /> I3. Phase Separated Hydrocarbon <br /> If phase-separated hydrocarbon (PSH) is encountered, its thickness in the well and the <br /> depth to the interface between the PSH and the water in the well are measured using one or both <br /> of the following methods <br /> • an electronic oil-water interface meter is used to measure the depths to the top of <br /> the PSH and to the top of the water, and/or <br /> • an electronic water level meter is used to measure the depth to the top of the water <br /> and a clear bailer is used to measure the PSH thickness <br /> The potentiometeric surface elevation is calculated as <br /> TOC - DTW + 0 74PT <br /> Where TOC=top-of-casing elevation, DTW=depth to water(interface), and PT=PSH <br /> thickness <br /> • <br />