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Home My WebLink AboutNCD980602163_19970310_Warren County PCB Landfill_SERB C_Methane Monitoring at the Landfill-OCRI State of North Carolina Department of Environment, Health and Natural Resources Division of Waste Management M, ~ -....-... ,, James B. Hunt, Jr., Governor Wayne McDevitt, Secretary William L. Meyer, Director MEMO TO: FROM: DATE: Mike Kelly Wendy Peacock March 10, 1997 DEHNR RE: Methane Monitoring at the Warren County Landfill BACKGROUND The Warren County landfill is similar to other landfills located within the state whereas it produces methane gas. Methane (CH4) is a colorless and odorless gas that is a by product of anaerobic decomposition. CH4 is lighter than air by volume and very volatile. If methane is in the 5 to 15% concentration range, a source of ignition will set off an explosion. Gas produced in the landfill move by two forces, diffusion and pressure gradient. Diffusion is the physical phenomenon that causes a gas to seek a uniform concentration. In other words, the gas will move away from areas of higher concentration towards areas of lower concentration. -The same is true for the pressure gradient. CH4 will move from higher zones of pressure to lower zones of pressure. Yet, changing barometric pressure, rainfall and frozen ground may also cause the gas to move in unpredictable or not previously observed directions. TESTING PROCEDURES Methane readings were conducted using the LANDTEC GA-90 gas analyzer. This instrument uses an infrared beam to analyze landfill specific gases such as methane, carbon dioxide and oxygen. A balance gas consisting of nitrogen and xylene with other atmospheric gases is also examined. The GA-90 gives a digital reading of landfill gases pumped through the machine to be analyzed. P.O. Box 29603, Raleigh, North Carolina 27611-9603 Telephon.e 919-733-4996 FAX 919-715-3605 An Equal Opportunity Affirmative Action Employer 50% Recycled/ 10'll, Post-Consume< Paper ,,. SAMPLING On January 29, 1997, during a routine inspection of the landfill, methane testing was conducted. This testing involved the use of the center vent as the methane source. Again the GA-90 was used as the measurement device. The data is located in Appendix A On January 13, 1997 the Warren County landfill was surveyed. The boundary of the plastic liner was identified and marked at 50' intervals and 12" deep bore holes were dug and capped for future evaluation. The testing was conducted on February 7, 1997. The results and location of the bore holes are located in Appendix B. Because of the previous rainfall some of the borehole were saturated with water, therefore a reading could not be conducted. Those locations are marked with an X. The last set of gas measurements were taken from the newly installed bore holes located on the south and north sides of the center vent. These wells were installed, on February 19 and 26, respectively, at a lower depth than the center vent. After each well was complete a methane reading was taken. A second reading was obtained after letting the well vent for 1 hour. The results of this sampling episode are located in Appendix C. APPENDIX A Code Time Date CH4 LEL CO2 02 Bal Atmospheric Pressure Temperature Depth % % % % % "Hg 0F Feet PCBOOCV 1:57 1/29/97 0.8 16 0.7 20.8 77.7 30 .4 42.7 24 PCBOOCV 2:01 1/29/97 1.1 22 0.7 20.8 77.4 30.4 48.3 24 APPENDIXB Code Time Date CH4 LEL CO2 02 Bal Atmospheric Pressure Temperature Depth % % % % % "Hg 0F Feet C0010001 10:11 2/7/97 0 0 0.7 18.6 80.7 29.8 approx47 1 C0010004 10:18 217197 0 0 0.1 20.3 79.6 29.8 1 C0010005 10:20 • 217197 0 0 0 20.5 79.5 29.8 1 C0010006 10:22 2/7/97 0 0 0.1 20.3 79.6 29.8 1 C0010007 10:24 217197 0 0 0.9 12.3 86.8 29.8 1 C0010008 10:27 2/7/97 0 0 0 20.5 79.5 29.8 1 C0010009 10:29 217197 0 0 0.4 20.1 79.5 29.8 1 C0010010 10:31 217/97 0 0 0 20.5 79.5 29.8 1 C0010011 10:32 2/7/97 0 0 0 20.5 79.5 29.8 1 C0010012 10:36 217197 0 0 1.3 18.4 80.3 29.8 1 C0010013 10:38 2/7/97 0 0 0 20.6 79.4 29.8 1 C0010015 10:42 217197 0 0 2.9 14.3 82.8 29.8 1 C0010016 10:44 217197 0 0 0 20.7 79.3 29.8 1 C0010017 10:46 217197 0 0 0 20.7 79.3 29.8 1 C0010018 10:48 217197 0 0 0 20.7 79.3 29.8 1 C0010022 10:52 217197 0 0 0 20.6 79.4 29.8 1 C0010024 10:55 217197 0 0 0 8.1 91.9 29.7 1 C0010025 10:57 217197 0 0 0.6 19.5 79.9 29.7 1 11 X 12 13 X 14 10 15 9 16 8 17 X=saturated 7 X 6 X X 5 X 4 18 3 X 2 19 1 22 X 21 X 20 APPENDIXC Code Time Date CH4 LEL CO2 02 Bal Atmospheric Pressure Temperature % % % % % "Hg 0F PCBMW1 1:46 2/19/97 32.7 654 12.4 8.7 46.2 29.6 PCB00CV 1:58 2/19/97 4.2 84 3.1 4.5 88.2 29.5 PCBMW2 9:05 2/27/97 64.5 1290 24.1 1.6 9.8 29.5 PCBMW1 10:49 2/27/97 44.1 882 14.3 7.8 33.8 29.4 PCBMW2 11 :02 2/27/97 35.3 706 13.4 10 41.3 29.4 PCB00CV 11 :29 2/27/97 0.1 2 0 20.7 79.2 29.4 Reference: To find PPM multiply %CfiJ by 10,000 CONCLUSION Methane gas concentrations are influenced by the barometric pressure and temperature. During the initial stages of testing the temperature ranged from the lower to mid 40's. As the testing increased through the month of February, temperatures did not change, although the barometric pressure was sparatic throughout the month. As the end of February approached, the normal North Carolina temperatures began to appear causing methane amounts to increase. As the monthly inspections continue, the methane ranges are expected to increase as temperatures increase. Methane production has a predicted life of 10 to 20 years during normal conditions. Using a plastic/synthetic liner limits the amount of water infiltration thus, reducing methane production. There appears to be sufficient water in the landfill such that gas production levels have not dropped significantly in the past 10 to 15 years. If the water were to be removed from the landfill, it is reasonable to predict that gas production would be significantly curtailed. cc: Bill Meyer Phil Prete Larry Rose Ed Mussier Depth Feet 28 24 29 29 28 24 State of North Carolina Department of Environment, Health and Natural Resources Division of Waste Management James B. Hunt, Jr., Governor Wayne McDavitt, Secretary William L. Meyer, Director MEMO DATE: TO: FROM: RE: October 6, 1997 Mike Kelly Wendy Peacock~ Methane Monitoring at the PCB Landfill Methane Monitoring was conducted at the PCB Landfill located in Warren County on Friday, October 3, 1997. Methane readings were taken using the LANDTEC GA-90 gas analyzer. The GA-90 uses an infrared beam to analyze the amount of methane, carbon dioxide and oxygen within landfill gas. As the monitoring plan indicated 12 inch bore holes were placed into the landfill surface using a bar punch probe. Each sample was taken in approximately 25 foot increments inside the landfill liner boundary. The results and locations for the bore holes are located in Appendix B. Additional readings were taken at the previously installed gas/water monitoring wells. TESTING PROCEDURES Monitoring began by taking readings from the installed monitoring wells, starting with the center vent and moving to the north and south areas. A reading was taken immediately after uncovering each well and then 2 hours later after venting. These readings are located in Appendix B. After recording the initial readings from the wells, the surface monitoring began. The four comers of the landfill cell boundary were approximately established, these are 116 feet from the center of the landfill on both the east and west side. The first bore hole and sample was made approximately 30 feet from the east side of the pump house. Then walking south, samples were taken every approximately 25' until the south cell boundary was reached (Line A: East side -PCBEA). Starting from the original bore hole a second line (Line EB) was established 35' east. Again samples were taken every 25' along the line. A final sample line (Line EC) was made 70' from the original bore hole and samples were taken every 25'. The same process was repeated on the west side of the pump house. (Line A: West side -PBCWA). A diagram of the sampling process can be found in Appendix A. P.O. Box 29603, Raleigh, North Carolina 27611-9603 Telephone 91~733-4996 FAX 91~715-3605 An Equal Opportunity Affirmative Action Em~!oyer 50% Recycled/ 10% Pos1-Consume< Paper RESULTS The temperature on the landfill was a consistent 67°F. Landfill conditions were overly very dry. This helped tremendously with obtaining accurate samples. The majority of the samples showed no amount of methane escaping through the surface of the landfill, especially on the west side. A few of the samples on the east side gave a low carbon dioxide reading along the surf ace. One east side sample showed a slight amount of methane (EB/1 ). After testing the rest of the line an additional bore hole was made from this location. No amount of methane gas was detected. This could be caused by not purging the system after each use. CONCLUSION Methane gas concentration are influenced by the temperature and barometric pressure. On the specific day of sampling the temperature and barometric pressure were constant throughout. Both cell boundary and random surface testing have not shown any amount of methane escaping through the landfill surf ace. Additional methane monitoring will continue on a monthly basis using the installed wells as a monitoring instrument. cc: Bill Meyer Phil Prete Larry Rose Ed Mussier r X X X X X X X X X South X X X X X X X X X X Code Time PCB -cent 12:03 PCB -north 12:10 PCB -south 12:14 PCB -cent 2:10 PCB -north 2:16 PCB -south 2:13 X X X X X X Appendix A X X X X X X X Center Vent X X X X X X * Orginal Bore Hole x Sample Taken Appendix B Gas Analyser Data: X X X X X X X Date CH4 CO2 02 % % 10/3/97 0 0 10/3/97 54.6 24.2 10/3/97 1.8 1.9 10/3/97 0 0 10/3/97 17.4 7.5 10/3/97 0.6 0.5 PCB Landfill Methane Monitoring % 20.6 3.5 18.2 20.5 14.6 19.3 X X X North X X X Bal Location % 79 .4 center vent 17.7 north well 78.1 south well 79.5 center vent 60.5 north well 79.6 south well EAST Code Time Date CH4 CO2 % % PCB EA/1 12:26 10/3/97 0 0 PCB EA/2 12:28 10/3/97 0 0 PCB EA/3 12:29 10/3/97 0 0 PCB EA/4 12:30 10/3/97 0 0 PCB EA/5 12:30 10/3/97 0 0.6 PCB EA/6 12:32 10/3/97 0 0 PCB EA/7 12:34 10/3/97 0 0 PCB EA/8 12:36 10/3/97 0 0 PCB EA/9 12:38 10/3/97 0 0 PCB EB/1 12:43 10/3/97 0.3 0 PCB EB/2 12:44 10/3/97 0 0 PCB EB/3 12:46 10/3/97 0 0 PCB EB/4 12:47 10/3/97 0 0.1 PCB EB/5 12:49 10/3/97 0 0 PCB EB/6 12:51 10/3/97 0 0 P,CB EB/7 12:52 10/3/97 0 0 PCB EB/8 12:54 10/3/97 0 0 PCB EB/9 12:56 10/3/97 0 0 PCB EB/10 12:58 10/3/97 0 0 PCB EC/1 1:03 10/3/97 0 0 PCB EC/2 1:05 10/3/97 0 0 PCB EC/3 1:07 10/3/97 0 0 PCB EC/4 1:09 10/3/97 0 0 PCB EC/5 1 :11 10/3/97 0 0 PCB EC/6 1 :13 10/3/97 0 0 PCB EC/7 1 :15 10/3/97 0 0 PCB EC/8 1 :16 10/3/97 0 0 PCB EC/9 1 :18 10/3/97 0 0.4 PCB EC/10 1 :19 10/3/97 0 0 02 Bal % % 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.4 79.3 20.6 79.4 20.6 79.4 20.5 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.6 79.4 20.1 79.5 20.6 79.4 Appendix B cont. PCB Landfill Methane Monitoring Code PCBWN1 PCBWN2 PCBWN3 PCBWN4 PCBWN5 PCBWN6 PCBWA/7 PCBWN8 PCBWN9 PCB WB/1 PCB WB/2 PCB WB/3 PCB WB/4 PCB WB/5 PCB WB/6 PCB WB/7 PCB WB/8 PCB WB/9 PCB WC/1 PCBWC/2 PCB WC/3 PCB WC/4 PCB WC/5 PCBWC/6 PCBWC/7 PCB WC/8 PCB WC/9 PCB WC/10 WEST Time Date CH4 CO2 02 Bal % % % % 1:26 10/3/97 0 0 20.6 79.4 1:27 10/3/97 0 0 20.6 79.4 1:29 10/3/97 0 0 20.6 79.4 1 :30 10/3/97 0 0 20.6 79.4 1:32 10/3/97 0 0 20.6 79.4 1:33 10/3/97 0 0 20.6 79.4 1:34 10/3/97 0 0 20.6 79.4 1:35 10/3/97 0 0 20.6 79.4 1:36 10/3/97 0 0 20.6 79.4 1:39 10/3/97 0 0 20.6 79.4 1:40 10/3/97 0 0 20.6 79.4 1:42 10/3/97 0 0 20.6 79.4 1:43 10/3/97 0 0 20.6 79.4 1:44 10/3/97 0 0 20.6 79.4 1:46 10/3/97 0 0 20.6 79.4 1:47 10/3/97 0 0 20.6 79.4 1:50 10/3/97 0 0 20.6 79.4 1:52 10/3/97 0 0 20.6 79.4 1:54 10/3/97 0 0 20.6 79.4 1 :55 10/3/97 0 0 20.6 79.4 1:57 10/3/97 0 0 20.6 79.4 1:58 10/3/97 0 0 20.6 79.4 1 :59 10/3/97 0 0 20.6 79.4 2:01 10/3/97 0 0 20.6 79.4 2:02 10/3/97 0 0 20.6 79.4 2:03 10/3/97 0 0 20.6 79.4 2:05 10/3/97 0 0 20.6 79.4 2:07 10/3/97 0 0 20.6 79.4