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Home My WebLink About0601_AveryCountyMSWLF_LFG_DIN28179_20161027 November 21st, 2016 Ms. Jaclynne Drummond NCDENR DWM Solid Waste Section 2090 U.S. 70 Highway Swannanoa, North Carolina 28778-8211 RE: Operations, Monitoring, and Maintenance Report –Oct 2016 Avery County Closed MSW Landfill Spruce Pine, North Carolina Dear Ms. Drummond: Smith Gardner, Inc. (S+G) is pleased to present this report concerning the operation and maintenance (O&M) of the Avery County Closed MSW Landfill (Permit No. 06-01) Landfill Gas Collection and Control System (LFGCCS) and monitoring of the on- and off-site landfill gas probes for the October 2016 monitoring period. Mr. Spencer Holloman with S+G performed the site visit on October 27th, 2016. Site visit details are provided below. LFG EXTRACTION WELL MONITORING PROGRAM Monthly monitoring of the LFGCCS will continue and shall include the following items:  CH4, O2, CO2, and pressure monitoring at each extraction well head;  CH4, O2, CO2, and pressure monitoring at the flare station; and  Adjustment of the LFGCCS to balance recovery and ensure safe system operation. The County will maintain this LFGCCS and will continue to evaluate the effectiveness of increased LFG recovery from the waste mass in alleviating off-site LFG migration. Results from monthly monitoring events will be reported in accordance with the approved LFG Monitoring Plan. LFG EXTRACTION WELL MONITORING ACTIVITIES S+G personnel performed the flare station and well field monitoring on October 27th, 2016. Initial measurements indicated there was approximately 34 inches of available vacuum average throughout the well field, ranging from approximately 31 to 37 inches of available vacuum at each of the LFG wells across the well field. The results from this event are summarized below. Recommended actions are underlined. Well field data and flare station data are provided in the attached Table 1. Ms. Drummond November 21, 2016 Page 2 of 3 LFG Extraction Well Field  W-1 through W-10: S+G performed methane (CH4), oxygen (O2), carbon dioxide (CO2), and pressure monitoring. Valves on extraction Wells W3 through W9 were opened slightly.  Orifice Plates: S+G continues to evaluate orifice plate sizes at wells W5, W7, W9, and W10 during each site visit. As LFG flow potential at these locations remains stable, the correct orifice plate sizes are currently installed. Flare Station  Condensate Tank: The condensate tank was observed during this site visit; the liquid was at an acceptable level. S+G will continue to monitor the liquid level of the condensate tank.  Filter Tank: The filter tank was observed during the October 2016 site visit and the liquid level was found to be at an acceptable level. S+G will continue to monitor the liquid level of the filter tank.  Flare operation: Due to low concentrations of methane measured at the flare combustion not observed. The spark generator was however, operational. The flare was not able to be ignited prior to S+G leaving the site. S+G will continue to adjust the system to optimize gas flow and quality. LFG MONITORING WELL (PERIMETER) MONITORING PROGRAM Mr. Holloman performed monitoring of the perimeter LFG monitoring network during this event. Monitoring wells P-2, P-3 and P-7 exhibited methane concentrations of 25.7%, 10.5% and 9.9% respectively. Monitoring Well P-13 exhibited .1% methane (2% LEL). All other wells, monitored during this event, had no detectable concentrations of CH4. Results of this monitoring event are included in Attachment 1. Attachment 2 provides a CH4 concentration graph over time for monitoring wells that have historically had methane present. The current well network will continue to be monitored and data will be reported to NCDEQ and the County. CONCLUSIONS The site has been generally characterized (since recent system improvements) by a trend of consistently decreasing LFG concentrations. Elevated methane concentrations were observed in a select few wells during this monitoring event. These detections may be attributable to the extremely dry conditions currently present. We will continue to monitor the CH4 concentrations at the site monthly. Ms. Drummond November 21, 2016 Page 3 of 3 The next routine monitoring event is scheduled for November 2016. If you have any questions, or require additional information, please contact us at your earliest convenience at 919-828-0577 or by e-mail (address below). Sincerely, SMITH GARDNER, INC. Britt Ransom Madeline German, P.G. Project Manager, ext. 301 Project Geologist ext. 222 britt@smithgardnerinc.com madeline@smithgardnerinc.com Attachments cc: Eric Foster – Avery County Deb Aja – NCDENR file H:\Projects\Avery County (NC)\Avery-15-1 (LFG Sys Ops)\2016 LFG Monitoring\10 October 2016\Avery Co MSW LFG Monitoring Rpt Oct 2016.docx This page intentionally left blank. FIGURE This page intentionally left blank. 0 2 0 0 ' 4 0 0 ' 123 456 4 G:\CAD\Avery County\Avery 13-6\sheets\AVERY-B0216.dwg - 12/3/2013 11:03 AM Th i s P a g e I n t e n t i o n a l l y L e f t B l a n k TABLE This page intentionally left blank. DATE: BY:SWH Date/Time CH4 CO2 O2 Balance Init. Temperature Init. Static Pressure Adj. Static Pressure Adj. Diff. Pressure*Init. Flow Adj. Flow System Pressure mm/dd/yyyy %%%%deg F in H2O in H2O in H2O Scfm Scfm in H2O AVERY-W1 10/27/2016 16:34 73.1 26.3 0.5 0.1 NR -36.9 -36.9 0.0 0.0 0.0 -36.5 AVERY-W2 10/27/2016 16:39 48.9 25.9 0.5 24.4 NR -37.6 -37.7 0.0 0.0 0.0 -37.8 AVERY-W3 10/27/2016 16:52 66.7 27.4 1.0 4.7 NR -25.4 -25.5 0.1 8.0 8.0 -32.0 AVERY-W4 10/27/2016 16:43 27.7 22.7 2.9 50.5 NR -32.5 -32.3 0.2 18.0 15.0 -34.6 AVERY-W5 10/27/2016 17:04 28.3 23.7 0.6 47.4 NR -34.5 -34.4 0.1 3.5 3.4 -35.7 AVERY-W6 10/27/2016 17:00 8.9 18.9 2.7 69.4 NR -6.4 -6.2 0.2 18.0 20.0 -32.3 AVERY-W7 10/27/2016 16:57 9.3 20.8 0.8 63.8 NR -2.1 -2.0 0.1 0.8 0.8 -31.1 AVERY-W8 10/27/2016 17:09 15.6 20.7 2.9 60.9 NR -15.4 -14.8 0.6 16.0 19.0 -30.7 AVERY-W9 10/27/2016 16:29 10.1 18.3 4.8 66.6 NR -35.8 -35.7 0.1 0.7 0.7 0.3 AVERY-W10 10/27/2016 16:48 43.7 22.4 6.6 26.9 NR -36.7 -36.7 0.0 0.4 0.4 -36.5 Av-Flare 10/27/2016 17:15 12.9 9.7 12.6 64.7 NR NR NR NR NR NR NR NR= not recorded Landfill Gas Collection and Control System Monitoring October 2016 *The differential pressure measurement should be positive. A negative differential pressure may indicate no gas flow. Negative differential pressure can be the result of dirt or water obstructing the pitot tube perforations. Overpulling by adjacent extraction wells may also result in negative pressure being displayed. October 31, 2016 Avery County Closed MSW Landfill TABLE 1 Device ID Attachment 1 This page intentionally left blank. Attachment 2 This page intentionally left blank. By:DMM Updated by:BPR Date:11/18/2016 Methane Concetrations Between May 2011 and October 2016 Landfill Gas Monitoring Well Network Avery County MSW Landfill 0 10 20 30 40 50 60 70 80 Ma y - 1 1 Ju n - 1 1 Ju l - 1 1 Au g - 1 1 Se p - 1 1 Oc t - 1 1 No v - 1 1 De c - 1 1 Ja n - 1 2 Fe b - 1 2 Ma r - 1 2 Ap r - 1 2 Ma y - 1 2 Ju n - 1 2 Ju l - 1 2 Au g - 1 2 Se p - 1 2 Oc t - 1 2 No v - 1 2 De c - 1 2 Ja n - 1 3 Fe b - 1 3 Ma r - 1 3 Ap r - 1 3 Ma y - 1 3 Ju n - 1 3 Ju l - 1 3 Au g - 1 3 Se p - 1 3 Oc t - 1 3 No v - 1 3 De c - 1 3 Ja n - 1 4 Fe b - 1 4 Ma r - 1 4 Ap r - 1 4 Ma y - 1 4 Ju n - 1 4 Ju l - 1 4 Au g - 1 4 Se p - 1 4 Oc t - 1 4 No v - 1 4 De c - 1 4 Ja n - 1 5 Fe b - 1 5 Ma r - 1 5 Ap r - 1 5 Ma y - 1 5 Ju n - 1 5 Ju l - 1 5 Au g - 1 5 Se p - 1 5 Oc t - 1 5 No v - 1 5 De c - 1 5 Ja n - 1 6 Fe b - 1 6 Ma r - 1 6 Ap r - 1 6 Ma y - 1 6 Ju n - 1 6 Ju l - 1 6 Au g - 1 6 Se p - 1 6 Oc t - 1 6 P1 P3 P7 P11 P12 P13 P2 Well % CH4 by Installation of W9 and W10 (April 30, 2013) Installation of W9/P3 Connection (September 11, 2014 Installation of P7/W8 and P1/W10 Connection (September 3, 2015)