ARCHIVED REPORTS_XR0006498 - Laserfiche WebLink

Home Browse Search

CLEARWATER GROUP,INC Groundwater Monitoring and Sampling Protocols Groundwater Morutp= Prior to beguuungg,,a decontauunabon area is established. Decontarrtanation procedures consist of scrubbing downhole equipment man Alconox®solution wash(wash solution is pumped through ii ty pursing pumps used),and unsung in a first ruse of potable water and a second nese of potable water or detoruzed water if tfie latter is required Any non- ded=ted down hole equipment is decontaminated prior to use Prior to purging and samplung a well,the static water level is measured to the nearest 0 01 feet with an eiecrroruc water sounder Depth to bottom is scally measured once per you,at the request of the prolect manager,and during Clearwater s first visit to a site If hutoncal analytical data are not available, with which to establish a reliable order of increasing well contau=atior%,the water sounder and tape will be decontavunated between each well If floating separate-phase h#rocatbons (SPH)are suspected or observed,SPH is collected using a clear,open-ended product bailer,and the thickness is measured to the nearest 0 01 feet in the bailer SPH may alternatively be measured with an electronic interface probe. Axty txtorutoring well contauung a measurable thickness of SPIT before or during purging is not additionally purged and no sample is collected from that well Wells contau ung a hydrocarbon sheen are sampled unless otherwise specified by the project manager Field observations such as well intepgriey as well as water level measurements and floating product tlucknesses are noted on the Gauging Data/Purge Calcuations farm. Well E==g Each monitoring well to be sampled is purged lasing either a PVC bailer ora submersible pump Physical parameters (pH,temperature and conductivity)of the purge water are.monitored d pu rgi.�g activities to assess Y the water sample collected is representative of the agtalfer If regtured,parameters s�as dissolved oxygen,turbidtty,saliru etc are also measured are considered represmtative if parameter stabtbty is schleve� Stability is defused as a change of less than 0 25 pH uruts, less than 10%change in conductivity in micro mhos,and less than 10 degree centigrade(1.8 degrees Fatuieit)change m temperature Parameters are measured in a discreet sample detaivted from the bailer separately from the rest of the pvuge water Parameters are meastued at least four times during purging, uufiaft and at volume intervals of one well volume Purging continues until three well casing volumes have been removed or tintil the well completely dewaters Wells wluch dewater or demonstrate a slow recharge,may be sampled after fewer than three well volumes have bemv removed Well purging information is recorded on the Purge Data sweet All meters used to measure parameters are calibrated daily Purge water is sealed, labeled, and stored on site in DO T-approved 55-gallon d ums After b:eiavg Anemically profiled,the water is removed to an appropriate disposal faolity by a licensed waste hauler Groundwater Sample Collection Groundwater samples are collected immediately after purging or,if ptugmS rate exceeds well recharge rate,when the well has rechar ed to at least 80% of its static water level If recharge is extremely slow,the well is allowed to recharge for at least two hours,if practicable,or until sufficient volume hat,accumulated for sampling The well is sampled within 24 hours of purging or repiuged Samples are collected using Polyethylene bailers,either dssposable or dedicated to the well Samples being analyzed for compounds most sensitive to volatilization are collected Eirst Water samples are placed in ap}�ropriate laboratory-supplied containers,labeled,documented on a chain of custody form and placed on ice in a cooler for transport to a state-certified asnalyhcal laboratory Analytical detection limits match or surpass standards required by relevant local or regional guidelines Quality Assurance-Procedures To prevent contamination of the samples,CGI personnel adhere to the following procedures in the field • A new,clean pair of latex gloves are put on prior to sampling each well • Wells are gauged,purged and groundwater saris fes are collected in the expected order of increasing degree of contar=atton based on historical analytical results • All purging equipment will be thoroughly decontanunated between each well,using the procedtmes previously described at the beginning of this section • During sample collections for volatile organic analysis,the amount of air passing through the sample is mmuntzeed Thus helps prevent the air from st nppmg the volatiles from the water Sample bottles are filled by slowly runrung the sample down the side of the bottle until there is a convex meniscus over the mouth of the bottle 'Ilse lid is carefully screwed'onto the bottle:such that no air bubbles are present within the bottle If a bubble is present,the cap is removed and additional water is added to the sarnnple container After resealing the sample container,if bubbles still are present Inside, the sample container is discarded and the procedure is repeated with a new container I I t , l C[EARwATERCROt1P INC. 1 V 96.2 I; '66.1r. ' S/17 d I I I E' ' I I I n I! , E I I dfiOZi`o d31t1M6k1313 WdS0-TT i 86.1 6T' wnf ' I,