HomeMy WebLinkAbout16055-Loftis-Blythe-2017 Annual Methane Monitoring Report
2017 Annual Methane Monitoring Report
Loftis-Blythe Construction Site
(aka InnerLoop North Industrial Park)
5600 and 5518 David Cox Rd.
Charlotte, North Carolina
Brownfields Project No. 16055-12-060
H&H Job No. HTZ-001
February 23, 2018
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2017 Annual Methane Monitoring Report Loftis-Blythe Construction Site (aka InnerLoop North Industrial Park)
5600 and 5518 David Cox Rd.
Charlotte, North Carolina H&H Job No. HTZ-001
Table of Contents
Section Page No.
1.0 Introduction ................................................................................................................ 1
2.0 Background ................................................................................................................ 3
3.0 Quarterly Methane Monitoring, Alarms, and Annual System Testing ................ 5
3.1 Quarterly Methane Monitoring Results ................................................................... 5
3.2 Methane Warning System Alarm and Inspection .................................................... 6
4.0 Summary and Conclusions ........................................................................................ 8
List of Tables
Table 1 Methane Probe Monitoring Results
Table 2 Indoor Methane Monitoring Results
Table 3 Manhole & Trench Methane Monitoring Results
List of Figures
Figure 1 Site Location Map
Figure 2 Subsurface Methane Monitoring Probe Location Map
Figure 3 Indoor Methane Monitoring Location Map
Figure 4 Manhole & Trench Sample Location Map
Figure E2 Sensor Location Map
List of Appendices
Appendix A Equipment Calibration Documents
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2017 Annual Methane Monitoring Report Loftis-Blythe Construction Site (aka InnerLoop North Industrial Park)
5600 and 5518 David Cox Rd.
Charlotte, North Carolina H&H Job No. HTZ-001
1.0 Introduction
Hart & Hickman, PC (H&H), has prepared this Annual Methane Monitoring Report to document
quarterly methane monitoring and annual methane warning system inspection and testing
conducted at the Loftis-Blythe Construction Brownfields site (Brownfields Project No. 16055-
12-060) located at 5600 and 5518 David Cox Rd. in Charlotte, North Carolina. A site location
map is provided as Figure 1. The site consists of two industrial buildings (Building 1 and
Building 2) that were constructed in 2015 as part of redevelopment of the site. Building 1 (5600
David Cox Rd.) is located in the western portion of the site and is approximately 300,000 sq ft,
and Building 2 (5518 David Cox Rd.) is located in the eastern portion of the site and is
approximately 100,000 sq ft. A site layout is provided on Figure 2.
The methane monitoring and methane warning system inspection and testing were conducted in
accordance with the June 12, 2017 Methane Warning System Installation Report provided to the
Brownfields Program. The quarterly methane monitoring was conducted in June 2017,
September 2017, and December 2017 and included the collection of methane readings from four
subsurface methane monitoring probes, ambient air methane readings from Building 1 and
Building 2, and methane readings from sewer manholes and a drainage trench located in the
vicinity of Building 2. In addition, during the December 2017 quarterly methane monitoring
event, inspection and testing of the methane warning system installed in the western portion of
Building 2 was conducted. The western portion of Building 2 was occupied by JD Generators
until December 2017. JD Generators has moved out and the western portion of Building 2 is
currently vacant.
Additionally, the current landowner has elected to install methane vent wells within the footprint
of the landfill and adjacent to the building, in order to reduce the buildup of methane gas within
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the landfill, and reduce or eliminate the migration of such gas under the building slab. A work
plan detailing the proposed installation of six methane vent wells was submitted to the
Brownfields program on October 19, 2017 by Engineering Consulting Services (ECS). The work
plan was approved by the Brownfields program on December 12th, 2017 with the contingency of
the installation of a seventh vent well in the southern end of the footprint of the landfill. In
January 2018, ECS installed the methane vent wells at the site. Five methane vent wells were
installed within the footprint of the landfill and two vent wells are were installed between the
landfill and Building 2. Locations of the methane vent wells are shown on Figure 2.
A brief summary of the site background is provided in Section 2.0, and the results of the methane
monitoring and methane system inspection and testing are provided in Section 3.0.
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2.0 Background
Loftis Construction (also listed as Blythe Construction) previously occupied the property from
the 1970s to 1983 and operated a permitted land clearing and inert debris landfill in the central
portion of the site. The landfill was closed in 1984, and a notice was placed on the deed
indicating the location of the buried materials. The estimated extent of the landfilled materials
based upon the test pits is indicated in Figure 2. Results of test pits conducted as part of previous
assessment activities indicated that the materials present in the landfill consist of soil, rock, tires,
stumps, trees, woody debris, bricks, concrete, rebar, scrap metal, paper trash, and plastic.
In July 2013, H&H conducted Brownfields assessment activities at the site. As part of the
assessment activities, H&H conducted methane monitoring in and around the area of the former
landfill. The methane monitoring conducted during the Brownfields assessment included the
installation of 11 temporary methane probes. Five of the probes (MP-1, MP-6, MP-7, MP-10,
and MP-13) were installed within the landfill area (as identified by previous test pits), and six of
the sample locations (MP-2, MP-8, MP-9, MP-11, MP-12, and MP-14) were installed at
locations around the perimeter of the identified landfill area. The locations of the temporary
methane probes are shown on Figure 2.
The results of the initial methane monitoring indicated that MP-10 contained a concentration of
methane below the North Carolina Department of Environmental Quality (DEQ) Solid Waste
screening level of 100% of the LEL (5% methane) for property boundaries, but above the
screening level of 20% of the LEL (1.25% methane) for interior air. No other methane probes,
including methane probes surrounding MP-10, contained concentrations of methane above the
Regulation Level. The results of the methane monitoring in July 2013 are provided in Table 1.
Based on the results of the methane monitoring during the 2013 Brownfields assessment
activities, a methane monitoring plan was included in the Environmental Management Plan
(EMP) for the site to further evaluate subsurface methane concentrations as part of and after
construction activities. The methane monitoring plan included the installation and monitoring of
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four methane monitoring probes installed in the vicinity of previous methane monitoring probe
MP-10.
In accordance with the approved EMP, methane monitoring probes were installed in January
2015 and monitored approximately semi-annually (some events were delayed due to rainy
weather conditions preceding or on the planned sampling day) after completion of the
construction of the site buildings. The results of the methane monitoring indicated increasing
levels of methane in probes MP-15, MP-16, and MP-10R near Building 2 (Figure 2 and Table 1).
As shown on Figure 2, the highest concentrations of methane were measured in MP-16 located
closer to the center of the landfill area. Because of the elevated levels of methane detected in the
probes, H&H also measured methane in indoor air in both buildings during the last two
monitoring events (August 2016 and March 2017) to ensure that there was not an imminent
hazard, and no methane was detected.
Based on the results of the post-building construction methane monitoring, the property owner
at the time submitted a Methane Warning System Design Plan (Design Plan) for the western
portion of Building 2 to the Brownfields Program on May 16, 2017. In addition to the installation
of a methane warning system, the Design Plan included quarterly monitoring of subsurface
methane probes and possible methane accumulation areas (i.e. manholes and trenches), indoor
air monitoring for methane, and inspection and testing of the methane warning system.
Following approval of the Design Plan, the methane warning system was installed in the western
portion of Building 2 in May 2017. A report documenting the installation of the methane
warning system (Methane Warning System Installation Report) was provided to the Brownfields
Program on June 12, 2017. A summary of the quarterly methane monitoring and methane
warning system inspection and testing is included in the following section.
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3.0 Quarterly Methane Monitoring, Alarms, and Annual System Testing
In accordance with the approved Design Plan, H&H conducted quarterly monitoring of methane
probes MP-10R, MP-15, MP-16, and MP-17 and collected ambient air methane readings from
inside Building 1 and Building 2. Locations of the methane probes and ambient air samples are
shown on Figure 2 and Figure 3, respectively. During each quarterly visit, the sanitary sewer
manholes north of Building 2 and drainage trench south of Building 2 were also screened for
methane. Locations of the sewer manholes and drainage trench are shown on Figure 4. In
addition, as part of the monitoring, unpaved and paved areas were inspected for the presence of
settlement areas which could be locations of potential methane gas accumulation.
Quarterly monitoring events were conducted on June 30, 2017, September 28, 2017, and
December 27, 2017. Methane levels in the monitoring probes, ambient air samples, sewer
manholes, and drainage trench were collected utilizing a calibrated Landtec GEM 5000.
Equipment calibration documents for the Landtec GEM 5000 are provided as Appendix A. The
readings collected during monitoring included methane, carbon dioxide, and oxygen. During the
monitoring events, an in-line carbon filter was used. Prior to sampling, the carbon filter was
conditioned with methane in accordance with the manufacturer’s specifications prior to
monitoring.
During the quarterly methane monitoring event conducted on December 27, 2017, the annual
methane warning system inspection and testing was also performed. The inspection included
verifying communication of the sensors to the central control panel, testing a representative
number of sensors, and confirming that each sensor’s green “armed” light was illuminated at the
time of the inspection. The methane warning system layout is provided on Figure E2.
3.1 Quarterly Methane Monitoring Results
The results of methane monitoring conducted in June, September, and December 2017 indicated
the presence of methane in MP-16 (ranging from 36.1% to 40.3%), MP-10R (ranging from
13.5% to 15.5%), and MP-15 (ranging from 13.1% to 13.8%) above the most conservative
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methane screening level of 1.25% during each of the quarterly monitoring events. Methane was
also detected in MP-17 (ranging from 0.1% to 0.2%) during the quarterly monitoring events, but
the concentrations detected were below the most conservative methane screening level of
1.25%. In general, the methane concentrations detected were consistent with recent and previous
methane monitoring events conducted at the site and methane concentrations detected in the
subsurface monitoring points appear to be stable. A summary of the methane probe readings is
provided in Table 1.
Methane was not detected inside either of the two buildings at the site during the quarterly
methane monitoring events. In addition, methane was not detected in the sanitary sewer
manholes or trench drain during the quarterly methane sampling events except for a trace
detection (0.1%) detected in the two manholes in September 2017. The results of the site
inspections did not indicate the presence of settlement areas at the site that could result in
potential accumulation of methane gas. Results of indoor air methane monitoring conducted at
the site are provided as Table 2 and depicted on Figure 3. Results of manhole and trench
methane monitoring conducted at the site are summarized in Table 3 and depicted on Figure 4.
3.2 Methane Warning System Alarm and Inspection
On December 22 and 26, 2017, the methane alarm system installed in the western portion of
Building 2 was triggered and a notification was sent to the appropriate parties. The alarms
occurred while building tenant (JD Generators) was moving out and operating lifts and trucks
inside the space to transport the contents of the building. It was determined that the alarms were
likely triggered as a result of exhaust generated from the moving equipment and H&H confirmed
that methane was not present in the building during the December 27, 2017 monitoring event.
During the December 2017 quarterly methane monitoring event, the methane alarm system was
inspected by H&H in accordance with the Design Plan. The inspection included observing the
alarm system panel for faults, testing a representative number of methane sensors, and ensuring
that the green “armed” light was illuminated on each of the sensors.
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While checking the system panel, a “fault zone 8” message was observed on the display screen
of the panel. A diagnosis of the source of the fault in zone 8 was then performed by individually
triggering sensors in zone 8 by releasing small amounts of propane into the sensor. Two faulty
sensors were replaced as a result of the test and the system was reset. The sensors were then
tested a second time to ensure that the faulty sensors had been replaced with a passing result for
detectors in all 8 zones. The methane alarm system was then modified to send a message to the
appropriate parties in the event of a fault in any of the 8 zones.
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4.0 Summary and Conclusions
The results of the June, September, and December 2017 quarterly methane probe monitoring
events indicated concentrations of methane in MP-16, MP-10R, and MP-15 above the most
conservative methane screening level of 1.25%. Detected methane concentrations are consistent
with recent previous methane monitoring events conducted at the site and appear to be stable.
Methane was not detected in ambient air inside either of the two buildings at the site or the
trench drain near Building 2 during the quarterly methane monitoring events. Trace methane
(0.1%) was detected in two manholes near Building 2 in September 2017 only and is not
considered significant. In addition, settlement areas where methane gas could potentially
accumulate were not observed during the quarterly monitoring events.
To date, methane has not been observed in ambient air in either of the two on-site buildings or
potential receptors in the vicinity of the landfill area. However, as a precautionary measure, the
current landowner elected to install seven methane gas vent wells to assist with the ventilation
and migration of methane gas within and around the landfill area. A work plan detailing the
proposed installation of six methane gas vent wells was submitted to the Brownfields program on
October 19, 2017 by ECS. In January 2018 ECS installed the methane vent wells at the site. Five
methane vent wells were installed within the footprint of the landfill and two vent wells are were
installed between the landfill and Building 2.
The methane alarm system was triggered on two separate occasions in December 2017, but it
was determined that the sensors were likely triggered from the exhaust of equipment used by the
building tenants during move out of the building. H&H confirmed that methane was not present
in the building during the December 2017 quarterly monitoring event.
In accordance with the Design Plan, H&H conducted a methane warning system inspection in
December 2017. Two faulty sensors were replaced as a result of the test and the system was
reset. The sensors were then tested to ensure that the faulty sensors had been replaced with a
passing result for detectors in all 8 zones.
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In accordance with the Design Plan, H&H will continue quarterly monitoring and perform an
annual methane warning system inspection in 2018. Following the December 2018 sampling
event, H&H will provide the 2018 Annual Methane Monitoring Report. The report will include
the methods and results of the quarterly methane monitoring and annual methane warning system
inspection. In addition, the 2018 Annual Methane Monitoring Report will include
recommendations for continued methane monitoring (i.e. locations and sample frequency). The
next quarterly methane monitoring event is scheduled for March 2018.
TABLES
Table 1
Methane Probe Monitoring Results
Loftis-Blythe Construction Site
(aka Innerloop North Industrial Park)
5600 and 5518 David Cox Rd
H&H Job No. HTZ-001
Ambient 0.1 0.0 20.5 79.2
Subsurface 0.2 1.7 18.9 79.0
Ambient 0.0 0.0 20.6 79.1
Subsurface 0.2 0.2 20.5 79.2
Ambient 0.1 0.0 20.6 79.1
Subsurface 0.1 5.8 13.5 80.4
Ambient 0.1 0.0 20.6 79.1
Subsurface 0.1 2.2 17.1 80.3
Ambient 0.1 0.0 20.5 79.1
Subsurface 0.1 1.1 19.4 79.3
Ambient 0.1 0.1 20.5 79.3
Subsurface 0.1 1.5 19.5 79.2
Ambient 0.1 0.0 20.6 79.2
Subsurface 1.6 6.9 11.2 80.1
Ambient 0.1 0.1 20.5 79.1
Subsurface 0.2 2.3 18.0 79.4
Ambient 0.1 0.2 20.4 79.2
Subsurface 0.1 3.6 18.3 77.9
Ambient 0.1 0.0 20.6 79.1
Subsurface 0.2 2.1 18.3 79.3
Ambient 0.1 0.0 20.5 79.3
Subsurface 0.1 1.2 18.1 80.4Ambient 0.0 0.6 21.4 78.0Subsurface0.0 6.8 2.8 90.0
Ambient 0.0 0.1 20.9 78.8Subsurface4.2 9.7 0.2 85.0
Ambient 0.1 0.8 22.1 77.0Subsurface11.6 13.1 0.9 74.4
Ambient 0.0 0.1 20.8 79.1Subsurface16.0 10.8 0.5 72.6
Ambient 0.0 0.2 20.5 79.3Subsurface14.9 11.2 0.9 73.0
Ambient 0.0 0.2 19.8 80.0Subsurface13.5 12.7 0.7 73.1
Ambient 0.0 0.3 20.1 77.8Subsurface15.5 11.5 0.0 73.0
Ambient 0.0 0.9 21.2 78.0
Subsurface 0.0 6.9 2.1 78.0
Ambient 0.0 0.2 20.7 79.1
Subsurface 2.6 11.1 0.6 83.9
Ambient 0.0 0.2 22.1 77.7
Subsurface 8.7 23.3 0.2 67.8
Ambient 0.0 0.1 21.4 78.5Subsurface12.4 23.1 0.8 63.4
Ambient 0.0 0.6 20.5 78.9Subsurface13.8 21.7 0.4 63.9
Ambient 0.0 0.2 19.5 80.3Subsurface13.1 24.3 0.2 62.4
Ambient 0.0 0.2 19.9 78.7Subsurface13.8 22.8 1.5 63.2
Ambient 0.0 0.4 21.4 78.1
Subsurface 31.3 16.4 0.5 51.5
Ambient 0.0 0.1 20.9 79.0
Subsurface 34.6 14.7 0.4 48.9
Ambient 0.1 0.2 22.8 76.9
Subsurface 46.0 16.0 1.2 36.8
Ambient 0.0 0.1 20.4 79.5Subsurface36.2 22.0 0.3 41.5
Ambient 0.0 0.7 20.5 78.9Subsurface36.1 17.5 1.9 44.0
Ambient 0.0 0.3 19.4 80.3Subsurface40.3 20.5 0.2 39.5
Ambient 0.0 0.1 20.0 78.4Subsurface39.5 19.5 0.4 40.8
Ambient 0.0 1.8 14.6 83.7
Subsurface 0.0 0.3 21.5 78.2
Ambient 0.0 0.1 20.8 79.2
Subsurface 0.0 5.7 0.4 93.0
Ambient 0.0 0.4 22.1 77.5
Subsurface 0.4 12.2 0.1 87.3
Ambient 0.0 0.1 19.9 80.0Subsurface0.6 8.7 2.4 88.0
Ambient 0.0 0.2 20.6 79.2Subsurface0.1 10.6 0.1 89.2
Ambient 0.0 0.5 19.8 79.8Subsurface0.1 11.6 0.2 87.9
Ambient 0.0 0.2 20.6 79.2Subsurface0.2 9.3 0.4 89.9
<1.25
NotesBold indicates concentration exceeds screening level.
Screening level based upon DEQ Solid Waste Section regulations for
facility structures of 25% LEL (1.25% methane).
MP = Methane Probe
Ambient Measurements were taken adjacent to MP locations immediatley prior to subsurface reading.
Readings collected with a conditioned in-line charcoal filter.
DEQ Soild Waste Section Sceening Level
Well ID Sampling
Date Ambient/Subsurface Location
(Landfill/Perimeter)Methane (CH4)Carbon dioxide (CO₂)Oxygen (O2)BalancePercent (%)
MP-1 07/17/13 Landfill
MP-2 07/17/13 Perimeter
MP-6 07/17/13 Landfill
MP-7 07/17/13 Landfill
MP-8 07/17/13 Perimeter
MP-9 07/17/13 Perimeter
MP-10 07/17/13 Landfill
MP-11 07/17/13 Perimeter
MP-12 07/17/13 Perimeter
MP-13 07/17/13 Landfill
MP-14 07/17/13 Perimeter
04/02/15
11/17/15
LandfillMP-10R
12/27/17
03/08/17
08/04/16
Perimeter
06/30/17
09/28/17
03/08/17
11/17/15
08/04/16
04/02/15
11/17/15
08/04/16
06/30/17
MP-17
12/27/17
09/28/17
LandfillMP-16
12/27/17
06/30/17
06/30/17
09/28/17
09/28/17
MP-15 Perimeter
12/27/17
03/08/17
03/08/17
04/02/15
04/02/15
11/17/15
08/04/16
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Table 1
Hart & Hickman, PC
Table 2
Indoor Methane Monitoring Results
Loftis-Blythe Construction Site
(aka Innerloop North Industrial Park)
5600 and 5518 David Cox Rd
H&H Job No. HTZ-001
8/4/2016 0.0 0.4 22.5 77.1
3/8/2017 0.0 0.2 21.0 78.8
6/30/2017 0.0 0.2 20.6 79.1
9/28/2017 0.0 0.2 19.7 80.1
12/27/2017 0.0 0.4 19.9 78.5
8/4/2016 0.0 0.1 22.8 77.1
3/8/2017 0.0 0.1 21.1 78.8
6/30/2017 0.0 0.2 20.8 79.1
9/28/2017 0.0 0.2 19.6 80.2
12/27/2017 0.0 0.3 19.9 78.6
8/4/2016 0.0 0.1 22.8 77.1
3/8/2017 0.0 0.1 21.1 78.8
6/30/2017 0.0 0.2 20.7 79.1
9/28/2017 0.0 0.2 19.9 79.9
12/27/2017 0.0 0.2 20.0 78.8
8/4/2016 0.0 0.1 22.7 77.2
3/8/2017 0.0 0.1 21.1 78.8
6/30/2017 0.0 0.2 20.9 78.9
9/28/2017 0.0 0.2 19.7 80.1
12/27/2017 0.0 0.3 19.8 78.7
8/4/2016 0.0 0.1 23.0 76.9
3/8/2017 0.0 0.1 21.3 78.6
6/30/2017 0.0 0.3 20.7 79.0
9/28/2017 0.0 0.2 19.9 79.9
12/27/2017 0.0 0.2 19.9 78.1
8/4/2016 0.0 0.1 22.9 77.0
3/8/2017 0.0 0.1 21.3 78.6
6/30/2017 0.0 0.2 20.8 79.0
9/28/2017 0.0 0.2 19.9 79.9
12/27/2017 0.0 0.2 19.9 78.1
8/4/2016 0.0 0.1 23.1 76.8
3/8/2017 0.0 0.1 21.2 78.7
6/30/2017 0.0 0.2 20.8 79.0
9/28/2017 0.0 0.2 20.0 79.9
12/27/2017 0.0 0.3 19.8 78.0
8/4/2016 0.0 0.1 23.2 76.7
3/8/2017 0.0 0.1 21.3 78.6
6/30/2017 0.0 0.2 20.9 78.9
9/28/2017 0.0 0.1 20.0 79.9
12/27/2017 0.0 0.2 19.9 78.1
DEQ Soild Waste Section Sceening Level <1.25
Notes
Screening level based upon DEQ Solid Waste Section regulations for
facility structures of 25% LEL (1.25% methane).
Ambient Measurements were taken at breathing zone level from ground.
AMB = ambient air
Readings collected with a conditioned in-line charcoal filter.BalanceMethane (CH4)Carbon dioxide (CO₂)Oxygen (O2)Well ID Sampling
Date Location Percent (%)
AMB-1 Building 1
Building 1
Building 1
AMB-4
Building 2
Building 2
AMB-3
AMB-2
Building 1
Building 2
Building 2
AMB-8
AMB-6
AMB-7
AMB-5
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Table 2
Hart & Hickman, PC
Table 3
Manhole & Trench Methane Monitoring Results
Loftis-Blythe Construction Site
(aka Innerloop North Industrial Park)
5600 and 5518 David Cox Rd
H&H Job No. HTZ-001
Ambient 0.0 0.1 20.6 79.3Subsurface0.0 0.1 20.4 79.5
Ambient 0.0 0.1 19.6 80.3Subsurface0.0 0.1 19.7 80.2
Ambient 0.0 0.2 19.8 78.6Subsurface0.0 0.2 19.9 78.6
Ambient 0.0 0.1 20.2 79.7Subsurface0.0 0.1 20.0 79.9
Ambient 0.0 0.1 19.8 80.1Subsurface0.1 0.1 20.0 79.8
Ambient 0.0 0.1 20.0 78.4Subsurface0.0 0.2 19.9 78.5
Ambient 0.0 0.1 20.0 79.9Subsurface0.0 0.2 20.0 79.8
Ambient 0.1 0.1 20.1 79.7Subsurface0.1 0.1 20.2 79.6
Ambient 0.0 0.1 20.0 78.3Subsurface0.0 0.2 19.9 78.2
Ambient 0.0 0.2 20.8 79.0Subsurface0.0 0.1 20.8 79.0
Ambient 0.0 0.2 19.3 80.5Subsurface0.0 0.2 19.4 80.5
Ambient 0.0 0.2 19.8 77.9Subsurface0.0 0.1 20.0 78.2
DEQ Soild Waste Section Sceening Level <1.25
Notes
Bold indicates concentration exceeds screening level.
Screening level based upon DEQ Solid Waste Section regulations for
facility structures of 25% LEL (1.25% methane).
Ambient Measurements were taken adjacent to manhole/trench
locations immediatley prior to subsurface reading.
Readings collected with a conditioned in-line charcoal filter.
Manhole-2
Manhole-3
Trench Methane (CH4)06/30/17
09/28/17
12/27/17
06/30/17
09/28/17
12/27/17
06/30/17
09/28/17
12/27/17
06/30/17
09/28/17
12/27/17
Manhole-1 Carbon dioxide (CO₂)Oxygen (O2)BalanceWell ID Sampling
Date Ambient/Subsurface Percent (%)
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Table 3
Hart & Hickman, PC
FIGURES
0 2000 4000
APPROXIMATE
SCALE IN FEET
N
U.S.G.S. QUADRANGLE MAP
QUADRANGLE7.5 MINUTE SERIES (TOPOGRAPHIC)
TITLE
PROJECT
SITE LOCATION MAP
LOFTIS-BLYTHE CONSTRUCTION SITE
5600 AND 5518 DAVID COX ROAD CHARLOTTE, NORTH CAROLINA
DATE:
JOB NO:
REVISION NO:
FIGURE:
01-26-18 0
1HTZ-001
SITE
2923 S. Tryon Street, Suite 100
Charlotte, NC 28203
704.586.0007(p) 704.586.0373(f)DERITA, NC 1996
MP-16
MP-15
DAVID C
O
X
R
O
A
D
BUILDING 1
(5600 DAVID COX ROAD)OLD STATESVILLE ROADMP-17
MP-2
MP-14
MP-12 MP-10
MP-13 MP-7
MP-8
MP-9
MP-11
MP-6
MP-1
MP-10R
PAVED
AREA
PAVED
AREA
BUILDING 2
(5518 DAVID COX ROAD)
OFFICES
OFFICES
WAREHOUSE
(VACANT)
WAREHOUSE
(TIRE WHOLESALES)
OFFICES
WAREHOUSE
BATHROOMS
WAREHOUSE
MVW-6
MVW-7
MVW-5
MVW-4
MVW-3
MVW-8
MVW-2
MVW-1
LEGEND
SITE PROPERTY BOUNDARY
CHAINLINK FENCE
APPROXIMATE EXTENT OF
LANDFILL AREA
PERMANENT METHANE PROBE
LOCATION
TEMPORARY METHANE PROBE
LOCATION (JULY 2013)
APPROXIMATE LOCATION OF
METHANE VENT WELL
DUKE POWER RIGHT-OF-WAY
JOB NO. HTZ-001
REVISION NO. 0DATE: 2-20-18
FIGURE NO. 2
LOFTIS-BLYTHE CONSTRUCTION SITE
5600 DAVID COX ROAD
CHARLOTTE, NORTH CAROLINA
SUBSURFACE METHANE MONITORING
PROBE LOCATION MAP
NOTE:
BOLD CONCENTRATION INDICATES
EXCEEDANCE OF DEQ SOLID WASTE
SECTION SCREENING LEVEL OF 1.25%.
CONSTITUENT CONCENTRATION %
METHANE PROBE ID
MP-10R 4/2/15 11/17/15 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 4.2 11.6 16.0 14.9 13.5 15.5
MP-15 4/2/15 11/17/15 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 2.6 8.7 12.4 13.8 13.1 13.8
MP-17 4/2/15 11/17/15 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.4 0.6 0.1 0.1 0.2
SAMPLE DATE
PAVED
AREA
PAVED
AREA
PAVED
AREA
PAVED
AREA
PAVED
AREA
MP-10R 4/2/15 11/17/15 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 4.2 11.6 16.0 14.9 13.5 15.5
MP-16 4/2/15 11/17/15 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 31.3 34.6 46.0 36.2 36.1 40.3 39.5
2923 South Tryon Street-Suite 100
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f)
License # C-1269 / #C-245 Geology
\\hhfs01.harthickman.local\masterfiles\AAA-Master Projects\Loftis-Blythe Brownfields site (HTZ)\Figures\Site Map.dwg, FIG 2, 2/20/2018 11:06:47 AM, zbarlow
MP-16
MP-15
DAVID C
O
X
R
O
A
D
BUILDING 1
(5600 DAVID COX ROAD)OLD STATESVILLE ROADMP-17
MP-10R
PAVED
AREA
PAVED
AREA
BUILDING 2
(5518 DAVID COX ROAD)
OFFICES
OFFICES
WAREHOUSE
(VACANT)
WAREHOUSE
(TIRE WHOLESALES)
OFFICES
WAREHOUSE
BATHROOMS
WAREHOUSE
AMB-6
AMB-5
AMB-8
AMB-7
AMB-3
AMB-2
AMB-4
AMB-1
MVW-6
MVW-7
MVW-5
MVW-4
MVW-3
MVW-8
MVW-2
MVW-1
AMB-1 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
LEGEND
SITE PROPERTY BOUNDARY
CHAINLINK FENCE
APPROXIMATE EXTENT OF
LANDFILL AREA
PERMANENT METHANE PROBE
LOCATION
AMBIENT AIR SAMPLE
APPROXIMATE LOCATION OF
METHANE VENT WELL
DUKE POWER RIGHT-OF-WAY
JOB NO. HTZ-001
REVISION NO. 0DATE: 1-15-18
FIGURE NO. 3
LOFTIS-BLYTHE CONSTRUCTION SITE
5600 DAVID COX ROAD
CHARLOTTE, NORTH CAROLINA
INDOOR METHANE MONITORING LOCATION MAP
NOTE:
BOLD CONCENTRATION INDICATES
EXCEEDANCE OF DEQ SOLID WASTE
SECTION SCREENING LEVEL.
CONSTITUENT CONCENTRATION %
METHANE PROBE ID
SAMPLE DATE
PAVED
AREA
PAVED
AREA
PAVED
AREA
AMB-1 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
AMB-2 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
AMB-3 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
AMB-4 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
AMB-5 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
AMB-6 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
AMB-8 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
AMB-7 8/4/16 3/8/17 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0 0.0 0.0
2923 South Tryon Street-Suite 100
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f)
License # C-1269 / #C-245 Geology
\\hhfs01.harthickman.local\masterfiles\AAA-Master Projects\Loftis-Blythe Brownfields site (HTZ)\Figures\Site Map.dwg, FIG 3, 2/20/2018 11:06:53 AM, zbarlow
MP-16
MP-15
MP-10R
MANHOLE-2
MANHOLE-3
MANHOLE-1
TR
E
N
C
H
-
1
MVW-7
MVW-8
MVW-2
BUILDING 2
(5518 DAVID COX ROAD)
LEGEND
SITE PROPERTY BOUNDARY
DUKE POWER RIGHT-OF-WAY
TRENCH DRAIN
SANITARY SEWER MANHOLE
PERMANENT METHANE PROBE
LOCATION
APPROXIMATE LOCATION OF
METHANE VENT WELL
JOB NO. HTZ-001
REVISION NO. 0DATE: 2-20-18
FIGURE NO. 4
LOFTIS-BLYTHE CONSTRUCTION SITE
5600 AND 5518 DAVID COX ROAD
CHARLOTTE, NORTH CAROLINA
MANHOLE & TRENCH SAMPLE LOCATION MAP
PAVED
AREA
OFFICES
OFFICES
WAREHOUSE
(VACANT)
WAREHOUSE
(TIRE WHOLESALES)
2923 South Tryon Street-Suite 100
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f)
License # C-1269 / #C-245 Geology
CONSTITUENT CONCENTRATION %
SAMPLE ID
MANHOLE-2 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0
SAMPLE DATE
MANHOLE-2 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.1 0.0
MANHOLE-3 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.1 0.0
MANHOLE-1 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0
TRENCH-1 6/30/17 9/28/17 12/27/17
METHANE 0.0 0.0 0.0
\\hhfs01.harthickman.local\masterfiles\AAA-Master Projects\Loftis-Blythe Brownfields site (HTZ)\Figures\Sample Location Map.dwg, FIG 4, 2/20/2018 11:06:32 AM, zbarlow
<EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> <EXIT> GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG12345678910118910891089108877777766666612345123451234512345123451234511111111111111AAAG11G11G11G11G11G11LOCATE INCABINETLOCATEABOVECEILINGGGENERAL NOTES:(APPLY THIS DETAIL ONLY)1.THIS DETAIL SHOWS HOW GAS DETECTION DEVICES ARE CONNECTED TOTHE ALARM CONTROL PANEL. CONTRACTOR SHALL CONNECT ALL GASDETECTION DEVICES IN SERIES FOR EACH N.O. INITIATING CIRCUIT TO BECONNECTED TO THE ALARM CONTROL PANEL.KEYED NOTES:(APPLY THIS DETAIL ONLY)CONTRACTOR SHALL PROVIDE AND INSTALL ALARM CONTROL PANEL.LOCATE IN VICINITY OF FIRE ALARM CONTROL PANEL. FIELD VERIFYLOCATION. CONNECT ALARM CONTROL PANEL TO 120 VOLT CIRCUIT THATSERVES EXISTING FIRE ALARM SYSTEM. INSTALL SO THAT CELLULARCOMMUNICATOR FOR ALARM PANEL CALLS OUT TO THIRD-PARTY CENTRALMONITORING STATION WHICH SHALL BE A NATIONWIDE UL/FMA COMPANY.CELLULAR COMMUNICATOR SELECTED SHALL BE A TOTAL CONNECTSYSTEM ALLOWING IT TO CALL MULTIPLE CELLULAR DEVICES. THE TOTALCONNECT THIRD-PARTY CENTRAL MONITORING SYSTEM SHALL CALL THESITE AND THEN DISPATCH FIRE/EMERGENCY SERVICES. THE THIRD PARTYCENTRAL MONITORING COMPANY SHALL CONTACT THE "CALL LIST" TOENSURE AWARENESS AND ALSO NOTIFY THE "CALL LIST" WHICH ZONE THEALARM OCCURS. THE ALARM ZONE CAN ALSO BE READ FROM THE GASDETECTION CONTROL PANEL KEYPAD.1#1 GAS DETECTIONALARM CONTROLPANELGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGZONE 1ZONE 2ZONE 3ZONE 4ZONE 5ZONE 6ZONE 7ZONE 8ZONE 9ZONE 10(2) WIRES FOR POWER AND (2)WIRES FOR ALARM SIGNAL FOREACH ZONE CIRCUITGAS DETECTION UNIT(TYPICAL OF ALL)GENERAL NOTES:(APPLY THIS DETAIL ONLY)1.REFER TO DETAIL 2/THIS DRAWING FOR GAS DETECTION SYSTEM INSTALLATION DETAIL.2.EACH GAS DETECTION ZONE CIRCUIT WILL BE MONITORED BY THE GAS DETECTION ALARMCONTROL PANEL AND THIRD-PARTY CENTRAL MONITORING COMPANY. IN THE EVENT OF A ALARMSIGNAL FROM A DEVICE, AN INDICATOR LIGHT FOR THE ZONE IN ALARM WOULD ILLUMINATE ONTHE KEYPAD ON THE CONTROL PANEL TO NARROW DOWN WHICH DEVICE IS IN ALARM. THEINDICATOR LIGHT FOR THE DEVICE IN ALARM WOULD BE ILLUMINATED ON THE DEVICE ITSELF.GGGGGGZONE 11GGGGGGGGGG5518 DAVID COX ROAD
GAS DETECTOR LOCATIONS FOR:
JDNA
HUNTERSVILLE, NORTH CAROLINASHEET :SHEET TITLE :OFCopyright 2017 Engitecture PLLC17045Project Number:05/19/17ENGITECTURE,PLLCNC License No. P-16253940 Amyington DriveCharlotte, NC 28226704-287-21931FLOOR PLAN - GAS DETECTIONGSYMBOL LEGENDMACURCO 'GD-2A' COMBUSTIBLE GAS DETECTOR (LAYOUT BASED ONMANUFACTURER RECOMMENDED 900SF COVERAGE AREA)CONTRACTOR SHALL PROVIDE AND INSTALL. SURFACE MOUNT ORINSTALL DEVICE OVER A FOUR-INCH SQUARE OR DOUBLE GANGJUNCTION BOX. DEVICES SHALL BE MOUNTED AT APPROXIMATELY 32'AFF.THE NUMBER NEXT TO EACH DEVICE DENOTES THE INITIATING DEVICEZONE CIRCUIT ON THE ALARM CONTROL PANEL THAT THE DEVICESHALL BE CONNECTED TO. CONTRACTOR SHALL CONNECT DEVICESTOGETHER ON EACH INITIATING ZONE CIRCUIT PER THE WIRINGDIAGRAM SHOWN ON DRAWING 1/E3 AND ROUTE EACH CIRCUIT TO THEALARM CONTROL PANEL.3/32" = 1'-0"E2FLOOR PLAN -GAS DETECTIONAAUDIBLE/VISUAL ALARM. COORDINATE EXACT LOCATION WITHMANUFACTURER OF GAS DETECTION SYSTEM.
Appendix A
Equipment Calibration Documents