6403_NashCDLF_March2017_Q2CDGasMonitoringTransittal_20170519

1100 Crescent Green Drive, Suite 208 • Cary, North Carolina 27518 • O: 919-792-1900 • F: 866-311-7206
June 30, 2017 Mr. William W. Hill, Jr., M.P.H. - Health Director Nash County Health Department P. O. Box 849 Nashville, NC 27856
RE: Results of Landfill Gas Monitoring – March 2017 Nash County C&D Landfill Nashville, Nash County, North Carolina Permit # 64-03
Dear Mr. Hill:
This letter presents the results of landfill gas monitoring conducted at the site referenced above on
May 18, 2017. Landfill gas was monitored using a calibrated GEM-2000 landfill gas monitor at the 12
on-site gas monitoring probes. A site map showing the locations of the landfill gas monitoring probes
is attached as Figure 1. The results of monitoring at each of the gas monitoring probes are
summarized in the attached Landfill Gas Monitoring Data Forms.

The landfill gas reading at MM-7 was greater than 100% of the lower explosive limit (LEL). The
methane reading at MM-7 was 9.2%. The % LEL and methane reading measured at this gas
monitoring probe is indicative of soil gas conditions proximal to an extensive stockpile of land clearing
debris, and not believed to be associated with the C&D landfill. Moreover, access to the site in the
vicinity of this probe is restricted to trained landfill personnel who are aware of these conditions.
Landfill gas and methane were not detected at any of the remaining gas monitoring probes.

The results of the May 2017 landfill gas monitoring are consistent with previous monitoring events
completed at the site, with the exception of the reading taken at location MM-7. The March 2017
reading at MM-7 was the first detection of soil gas in any probe associated with the C&D landfill. The
May 2017 reading was the second detection of soil gas. Therefore, the March and May of 2017
readings at location MM-7 are inconclusive, and not necessarily indicative of landfill gas migrating
laterally away from the buried waste.

There were some wells not sampled (MM-10, MM-12) due to the steel casing hinges being inoperable.
Inoperable hinges, or otherwise inaccessible probes, will be rehabilitated during the next scheduled
sampling event.

The next quarterly landfill gas monitoring event is scheduled for August 2017. If you have any
questions or require further assistance regarding this matter, please do not hesitate to call me at
Mr. William Hill
June 30, 2017 Page 2 of 2
919-792-1904.

Sincerely,
Garrett & Moore, Inc.

Craig M. Fortner, P.E.
Cc: Jaclynne Drummond, NCDENR, Division of Waste Management, Solid Waste Section Ben Barnes – Solid Waste Director, Nash County

NC Division of Waste Management - Solid Waste Section
Landfill Gas Monitoring Data Form
Notice: This form and any information attached to it are "Public Records" as defined in NC General Statute 132-1. As such, these documents are available for inspection and examination by any person upon request (NC General Statute 132-6).
Facility Name: Nash County C&D Landfill Permit Number: 64-03

Sampling Date: 05/18/17 NC Landfill Rule (.0500 or .1600): .0500

Sample Collector Name & Position: Isaac Hardison, EIT

Gas Meter Type & Serial Number: GEM 2000+, GM08230-05 Gas Meter Calibration Date: 05/16/17
Field Calibration Date & Time: 05/18/17, 9:45 AM
Field Calibration Gas Type (15/15 or 35/50): 35/50 CO2 & CH4 ; 50/25 CO & H2S
Field Calibration Gas Canister Expiration Date: 08/31/19
Gas Meter Pump Rate: NA
Ambient Air Temperature: 76 ̊ F Barometric Pressure (in. or mm Hg): 29.95mm Weather Conditions: Partially Cloudy
Instructions: Under “Location or LFG Well”, list monitoring well # or describe monitoring location (e.g., inside field office). Attach a test location map or drawing. Report methane readings as both % LEL and % CH4 by volume. Convert % CH4 (by volume) to % LEL as follows: % methane (by volume)/20 = % LEL. *Hydrogen Sulfide (H2S) gas monitoring may be required for Construction & Demolition Landfills (CDLFs). See individual permit conditions and/or Facility LFG monitoring plan.
Location or
LFG Well ID
Sample
Tube
Purge

Time of Day
Time
Pumped
(sec)
Initial % LEL
Stabilized % LEL
% CH4 (volume)

% O2 (volume)

% CO2 (volume)

% H2S* (volume)

NOTES
MM-1 1 min 14:23 60 0 0 0 15.2 3.20 0
MM-2 1 min 14:26 60 0 0 0 12.9 5.90 0
MM-3 1 min 14:32 60 0 0 0 15.4 3.50 0
MM-4 1 min 14:37 60 0 0 0 15.5 3.80 0
MM-5 1 min 14:42 60 0 0 0 16.0 6.00 0
MM-6 1 min 14:51 60 0 0 0 13.6 3.50 0
MM-7 1 min 13:10 60 2 >>> 9.20 4.10 7.40 0
MM-8 1 min 12:58 60 0 0 0 8.40 8.80 0
MM-9 1 min 13:03 60 0 0 0 14.7 5.70 0
MM-10 Hinge not operable
MM-11 1min 14:01 60 0 0 0 19.2 7.70 0
MM-12 Hinge not operable
NOTE: If needed, attach additional data forms to include additional LFG monitoring data locations for the facility. ACTION LEVELS: Methane: >1.25% by volume (inside structures) AND >5% by volume (at facility boundary) Hydrogen Sulfide: >1% by volume (inside structures) AND >4% by volume (at facility boundary)

Certification To the best of my knowledge, the information reported and statements made on this data submittal and attachments are true and correct. I am aware that there are significant penalties for making any false statement, representation, or certification including the possibility of a fine and imprisonment.
Professional Engineer
SIGNATURE TITLE
Revised – May 19, 2017