HomeMy WebLinkAbout2021-08-12 Nantucket Landfill Quarterly Gas Monitoring Report - June 2021
REPORT
Quarterly Landfill Gas
Monitoring – June 2021
Nantucket Landfill
Nantucket, Massachusetts
August 2021
75 State Street, Suite 701
Boston, Massachusetts 02109
tel: 617 452-6000
August 12, 2021
Mr. Mark Dakers
Massachusetts Department of Environmental Protection
Southeast Regional Office
20 Riverside Drive
Lakeville, Massachusetts 02347
Subject: Quarterly Landfill Gas Monitoring – June 2021
June 2021
Nantucket Landfill
Nantucket, Massachusetts
Dear Mr. Dakers:
On behalf of the Town of Nantucket, CDM Smith Inc. (CDM Smith) collected field analyzed landfill gas
samples on June 3, 2021 at the Nantucket Landfill located on Madaket Road in Nantucket,
Massachusetts. The quarterly landfill gas sampling was conducted to satisfy the monitoring
requirements of the Massachusetts Solid Waste Management Regulations (310 CMR 19.132) and was
conducted in accordance with the Environmental Monitoring Plan (EMP) for the Nantucket Landfill,
prepared by SECOR International Inc. in July 1999. This report presents the results of the June 2021
quarterly landfill gas monitoring.
Landfill Gas Monitoring
On June 3, 2021, CDM Smith sampled thirteen (13) landfill gas monitoring wells identified as LGW-1
through LGW-13 including two landfill gas probes identified as Probe-1 and Probe-2 for the presence of
landfill gas. The landfill gas probe locations are shown on the Site Plan. The landfill gas monitoring
program is conducted to confirm that landfill gas is not migrating off site.
For all landfill gas locations sampled, concentrations of methane (CH4), carbon dioxide (CO2), oxygen
(O2), hydrogen sulfide (H2S), and atmospheric pressure were obtained using a Landtec GEM 5000 Gas
Analyzer. The lower explosive limit (LEL) for methane was calculated based on the methane
concentration reading from the GEM 5000. VOC concentrations were obtained using a photoionization
detector (PID). Landfill gas wells and temporary landfill gas probes were purged for 10 minutes with the
Landtec Gas Analyzer prior to collection of final readings. The results of the landfill perimeter gas
monitoring are summarized in Table 1.
Mr. Mark Dakers
August 12, 2021
Page 2
Methane was not detected at any landfill gas well except for LGW-9 during the June 2021 landfill gas
monitoring round. At the start (initial), methane was detected at 440% of the LEL and upon completion
of purging (final), methane was detected at 376% of the LEL. Since methane was detected at LGW-9,
landfill gas probe-1 and probe -2 were installed and sampled approximately 10 feet and 20 feet to the
south of LGW-9, respectively. Methane was not detected at the two landfill gas probe locations.
In accordance with 310 CMR 19.132(4)(h), the MassDEP Southeast Regional Office (SERO) Solid Waste
Division was notified of the exceedance of the regulatory limit of 25% of the LEL at the property
boundary at landfill gas well LGW-9 in an email dated June 4, 2021. A copy of the notification email is
attached.
Hydrogen sulfide and VOCs were not detected at any landfill gas sampling locations during this
monitoring round. Carbon dioxide was detected at all landfill gas sampling locations, with
concentrations ranging from 0.2 to 9.2 percent volume. The results suggest that landfill gas is not
migrating off-site including the area adjacent to Massasoit Road where LWG-9 is located.
Conclusions and Recommendations
Results of the June 2021 landfill gas monitoring are consistent with historical results. The next quarterly
landfill gas monitoring round will be conducted in September 2021.
In accordance with 310 CMR 19.011 of the Massachusetts Solid Waste Regulations, please find the
attached certification of this report by the appropriate responsible official for the Nantucket Landfill in
Nantucket, Massachusetts.
Please contact Mary Mancini at (617) 452-6635 or Nicholas Castonguay at (617) 452-6721 if you have
any questions or require any additional information.
Very truly yours,
Mary Mancini, P.E. Nicholas Castonguay, P.G.
CDM Smith Inc. CDM Smith Inc.
Enclosures
cc: Elizabeth C. Gibson, Nantucket Town Manager
Table 1
Nantucket Landfill
Nantucket, Massachusetts
Landfill Gas Sampling Summary - June 2021
LEL (%)
Initial Final Initial Final Initial Final Initial Final Initial Final Initial Final
LGW-1 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.8 0.9 20.3 20.1 30.15
LGW-2 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.0 1.2 19.9 20.0 30.15
LGW-3 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.6 1.7 19.0 18.9 30.15
LGW-4 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.3 20.5 20.2 30.15
LGW-5 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 6.0 6.1 7.8 7.1 30.11
LGW-6 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 9.8 10.1 8.4 8.0 30.14
LGW-7 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 4.1 4.8 15.8 14.1 30.15
LGW-8 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.3 0.0 20.7 20.9 30.14
LGW-9 Well 6/3/2021 0.0 0.0 0.0 0.0 22 18.8 440 376 14.8 12.4 9.5 11.5 30.14
LGW-10 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.8 0.9 20.0 19.9 30.15
LGW-11 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.0 0.2 19.3 20.0 30.15
LGW-12 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.2 2.3 19.0 18.6 30.15
LGW-13 Well 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 20.9 20.9 30.14
Probe-1 Probe 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.0 1.9 19.2 19.2 30.14
Probe-2 Probe 6/3/2021 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.6 2.6 17.5 17.4 30.14
Notes:
(1) Landfill gas well and gas probes were purged for approximately 10 minutes before final readings were recorded.
(2) Methane (CH4), carbon dioxide (CO2), oxygen (O2) and hydrogen sulfide (H2S) were measured with GEM-5000 combustible gas meter.
(3) Volatile Organic Compounds (VOCs) measured with a Photoionization Detector (PID), lamp eV 10.6.
(4) Landfill gas probe 1 and probe 2 monitor gas migration at LGW-9; LGP-1 is approx 10 feet away from LGW-9; LGP-2 is approximately 20 feet away from LGW-9.
(5) Shaded values indicate that the results exceeds MassDEP limit of 25% LEL of methane.
LEL = Lower Explosive Limit
Hg = Mercury
Gas Monitoring Locations
H2S (ppm)CH4 (% by Vol.)CO2 (%)Barometric
Pressure (In.
Hg)
O2 (%)VOCs (ppmv)
Type Date
1
Castonguay, Nicholas J.
From:Castonguay, Nicholas J.
Sent:Friday, June 04, 2021 7:56 PM
To:Dakers, Mark (DEP); Ferguson, Colleen (DEP)
Cc:Robert McNeil; Graeme Durovich; Mancini, Mary; Santoro Jr, Frederic
Subject:Nantucket LF - June 2021 Landfill Gas Exceedance Notification
Attachments:Nantucket Landfill Environmental Monitoring Plan 3-13-13.pdf
In accordance with 310 CMR 19.132(5)(h), CDM Smith on behalf of the Town of Nantucket hereby notifies MassDEP that
during landfill gas monitoring on June 3, 2021, the concentration of methane gas exceeded 25% of the Lower Explosive
Limit (LEL) at one landfill gas well location (LGW-9) in southeast area of the landfill property. The location of the landfill
gas well locations are shown on the attached figure.
The concentrations of methane and LEL measured at LGW-9 are as follows:
Location Initial
Methane Initial LEL Final
Methane Final LEL
LGW-9 22.0% 440% 18.8% 376%
The LEL concentration is similar in range to previous landfill gas detections at this location. Landfill gas probes (LGP-1,
LGP-2, LGP-3) located adjacent to the property line were also installed as shown on the attached figure. Methane was
not detected at the three gas probe locations (LGP-1, LGP-2, LGP-3) nor any other gas sampling location during the June
2021 monitoring round.
Based on this information, it appears that the detected landfill gas remains limited to a small area at the southeast
corner of the landfill property adjacent to the composting pad and does not appear to be migrating off-site across
Massasoit Road where LWG-9 is located.
Please let me know if you have any questions or require anything further
Nick
Nicholas J. Castonguay, P.G.
CDM Smith
75 State Street
Boston, MA 02109
ph/fx: 617-452-6721
cell: 617-301-1763
email: castonguaynj@cdmsmith.com