COMPLIANCE INFO - Laserfiche WebLink

Home Browse Search

Monitoring Well Installation Workplan Page 5 of 6 Our Project Number: LES080548 July 10, 2008 2.3 Equipment Decontamination Drilling equipment including, but not limited to, samplers, drop hammers, drill rods, plug, augers, etc., will be cleaned prior to use at the drilling location. 3.0 WELL DEVELOPMENT It is anticipated that the groundwater monitoring well will be developed by mechanical surging and pumping no sooner then forty-eight hours after completion of the monitoring wells. Well development will be accomplished with an air-lift, submersible pump using an oil-less air compressor. Development will continue until the well water is clear to the unaided eye and the sediment thickness remaining in the monitoring well is less then 5 percent of the screen length. The turbidity goal is 50 NTUs. No acids, disinfectants, dispersing agents or other chemical additives will be used or introduced to the monitoring wells at any time. The wells will be allowed to recover for a minimum of 48 hours before purging and sampling. A log of the following will be produced for each monitoring well: Date the well was developed. The depth to water within the well prior to development along with time of measurement. The total depth of the well. Field measurements of the monitoring well water will occur prior to, twice during, and once after development. Filed measurements will include pH, specific conductivity, temperature and turbidity. In addition, color, clarity and odor will be noted. The amount of water removed will be recorded and as a minimum 10 borehole volumes should be removed from the well as part of the development. All water generated during development shall be disposed of on site. If any of the monitoring wells are pumped down to the point that no water con be removed from the well with out waiting a period of time (dry). The development will stop for five minutes and field measurements of the water will be collected and compared to the goals stated above. If the turbidly is above 50 NTUs or the sediment thickness is greater then 5 percent, additional pumping may be needed prior to completion of the development. Water will only be added for development of a dry well after approval from the City. 4.0 REPORT OF WELL INSTALLATION A Monitoring Well Installation Report will be compiled based largely upon the on-site geologist's boring logs. No deviations from this work plan are anticipated. However, should field conditions warrant modification of well construction plans identified in this document, then the deviations shall be documented in the well installation report. The on-site geologist will ensure that all drilling and well construction activities are consistent with common practice in the A 902 Industrial Way • Lodi, CA 95240 • 209.367.3701 • Fax 209.369.4228 02008 Neil 0. Anderson & Associates, Inc