Appendix I-2.2 Compliance Monitoring Well Status and New Well Installations

Transcription

1 Appendix I-2.2 Compliance Monitoring Well Status and New Well Installations

2 Appendix I-2 Groundwater Monitoring Network 2008/2009 Annual Groundwater Report, Clean Harbors Lambton Facility Landfill Appendix I-2.2 Compliance Monitoring Well Status and New Installations No new compliance monitoring wells were installed in the period from September 1 st, 2008 to August 31 st, Well Development Each well has been equipped with a dedicated Waterra inertial lift pump assemblage (i.e., high density polyethylene tubing with a foot valve connected to the down hole end). Newly installed wells are typically developed to remove any sediment and drill water introduced during drilling and well installation. The water used in drilling the wells is enriched in sulphate and depleted in sodium and chloride with respect to the bedrock formation water. Thus drill water is deemed to have been removed from the formation when sulphate decreased and stabilized to less than 5 mg/l, and the concentrations of sodium and chloride increases and typically stabilizes at values exceeding about 200 mg/l. Staff from Clean Harbors Canada, Inc. completes well development with assistance from AES staff. The development water is typically collected in calibrated containers and the water volume removed recorded. Water samples are periodically collected during well development and analyzed at the Lambton Facility on-site laboratory for ph, electrical conductivity, chloride, sodium, sulphate and fluoride. No compliance monitoring wells were undergoing well development between September 1, 2008 and August 31, J0008-T4 I-2.2-1

3 Appendix I-2 Groundwater Monitoring Network 2008/2009 Annual Groundwater Report, Clean Harbors Lambton Facility Landfill 1.2 Hydraulic Conductivity Testing A summary of the hydraulic conductivity results for wells installed between 1999 and 2005 are contained in Table I No additional compliance monitoring wells underwent hydraulic conductivity testing during the 2008/2009 monitoring period. The hydraulic conductivity across the screened zone of these wells was estimated using the Bouwer-Rice method. Hydraulic conductivity testing on interface aquifer wells completed in 1994 and 2005, have resulted in hydraulic conductivity values ranging from 1 x 10-4 m/s to 8.1x10-10 m/s with an average value of 2x10-7 m/s. Figure I presents a summary of hydraulic conductivity measurements in interface aquifer and shale aquitard wells and interpreted zones of higher hydraulic conductivity. A zone showing hydraulic conductivity of greater than 1x10-6 m/s was identified through the Purge Well Demonstration program, presented in the 2000/2001 Annual Landfill Report. In general, a zone of high hydraulic conductivity has been identified to extend in a north-south direction across the site. The interconnected zone of high hydraulic conductivity appears to extend off-site north of Sub-cell 3, Cell 18, south of the Pre-1986 Landfill and east of the East Reservoir. J0008-T4 I-2.2-2

4 Table I-2.2-1: Hydraulic Conductivity Results on Series Compliance Monitoring Wells Well Date Terminal Monitored Zone Hydraulic Testing General Comments Designation Installed Depth (mbgs) Progress HC (m/s) TW22-99D February 16, Interface Aquifer Completed 3.2 x 10-7 Artesian well. Water chemistry is representative of Shale Aquitard. TW30-99D March 4, Interface Aquifer Completed 6.8 x 10-5 Produces gas when purged. TW39-99S February 24, Clay Berm Fill Completed 3.2 x Slow recovery. TW39-99I February 24, Active Aquitard Completed > 1 x Very slow recovery. TW39-99D February 18, Interface Aquifer Completed 4.7 x 10-8 TW40-99S March 2, Active Aquitard Completed 1.2 x 10-9 TW40-99D February 26, Interface Aquifer Completed 7.8 x 10-7 TW41-99S March 10, Active Aquitard Completed 4.1 x Slow recovery. TW41-99D March 9, Interface Aquifer Completed 7.2 x 10-5 Produces gas when purged. TW42-99S March 11, Active Aquitard Completed > 1 x Very slow recovery. TW42-99D March 11, Interface Aquifer/Shale Aquitard Completed 2.2 x 10-9 Slow Recovery. Water chemistry is representative of Shale Aquitard. TW43-99S March 16, Active Aquitard Completed 2.2 x Slow recovery. TW43-99D March 16, Interface Aquifer Completed 3.2 x 10-6 Produces gas when purged. TW44-99S March 18, Active Aquitard Completed > 1 x Very slow recovery. TW44-99D March 18, Interface Aquifer/Shale Aquitard Not Completed Very slow recovery. Decommissioned on June 14, 2000 and replaced with well TW48-00D. TW45-99S March 12, Active Aquitard Completed 7.1 x 10-9 TW45-99D March 12, Active Aquitard/Shale Aquitard Completed 3.7 x 10-9 Slow recovery. TW46-99S August 9, Clay Berm Fill Completed 3.9 x Slow recovery. TW46-99I August 9, Active Aquitard Completed 7.7 x Slow recovery. TW46-99D August 9, Interface Aquifer Completed 8.4 x 10-7 TW47-00D June 22, Interface Aquifer Completed 3.2 x 10-7 Replacement well for TW21-94-I(D). TW48-00D June 16, Interface Aquifer Completed 8.1 x Slow recovery. Replacement well for TW44-99(D) TW49-00D June 20, Interface Aquifer Completed 1.4 x 10-9 Slow recovery. Replacement well for TW42-99(D) TW53-03S February 17, Active Aquitard Completed 1.2 x 10-9 TW53-03D February 17, Interface Aquifer Completed 7.2 x 10-6 OW35-05D February 2, Interface Aquifer Completed 1.4 x 10-6 Notes: (1) mbgs meters below ground surface (2) HC Hydraulic Conductivity

5 LEACHATE PETROLIA LINE CELL 18 CELL 17 RESERVOIRS TELFER ROAD CELL 16 EQUALIZATION RESERVOIR WEST RESERVOIR PRE LANDFILL AREA EAST RESERVOIR A SIZE 216 x 279 mm LEGEND OW1-92 3E-5 MONITORING WELL AND MEASURED HYDRAULIC CONDUCTIVITY TEST 3 3E-6 TEST WELL AND MEASURED HYDRAULIC CONDUCTIVITY K > 1E-6 m/s K = 1E-6 TO 1E-7 m/s K < 1E-7 m/s NOTES: 1. BASEMAP PROVIDED BY INSPEC-SOL INC. (2009). 2. AIRPHOTO PRODUCED BY FIRST BASE SOLUTIONS, (2006) m SCALE CLEAN HARBORS CANADA INC., LAMBTON FACILITY LANDFILL HYDRAULIC CONDUCTIVITY DISTRIBUTION IN THE INTERFACE AQUIFER PROJECT NUMBER J00008 DRAWING NUMBER I ISSUE/REVISION FILE: I dwg DATE PLOTTED: 18-Sep-09 DRAWN BY: TFB

6 Appendix I-2.3 Compliance Monitoring Well Construction Details