11037_Double Oaks_Methane VMS Report Rev 1 20230109

Via Email

January 9, 2023

NCDEQ – Division of Waste Management
Brownfields Program
1646 Mail Service Center
Raleigh, NC 27699-1646

Attn: Ms. Carolyn Minnich

Re: Methane VIMS Inspection and O&M Report – Revision 1
Phase 8 Brightwalk Development
Double Oaks Brownfields Site
Charlotte, Mecklenburg County
Brownfields Project No. 11037-07-060
H&H Project No. CHP-041

Dear Carolyn:

On behalf of DreamKey Partners, LLC, Hart & Hickman, PC is providing the attached Methane
VIMS Inspection and O&M Report – Revision 1 prepared for the above-referenced Site in
Charlotte, Mecklenburg County, North Carolina. The attached report has been revised in
accordance with comments received from the Brownfields Program on November 2, 2022.

If you have any questions or comments, please do not hesitate to contact us.

Sincerely,
Hart & Hickman, PC

John Lopez, PG Matt Bramblett, PE
Project Manager Principal

Enclosures

cc: Mr. Fred Dodson

Attachment: Methane VIMS Inspection and O&M Report – Revision 1
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Methane VIMS Inspection and O&M
Brightwalk Development-Phase 8
Charlotte, North Carolina
Brownfields Project No. 11037-01-060
H&H Job No. CHP-041

Table of Contents

1.0 Introduction .............................................................................................................................1 
2.0 MVIMS Inspection and O&M ................................................................................................6 
2.1 MVIMS Status and Data .......................................................................................................6 
2.2 Subslab Monitoring in Garages ...........................................................................................10 
2.3 Pre-Regulatory Landfill Methane Probe Monitoring ...........................................................11 
3.0 Summary and Recommendations .........................................................................................12 

List of Tables

Table 1 Summary of Landfill Gas Probe Data

List of Figures

Figure 1 Site Location Map
Figure 2 Site Map
Figure 3 Methane Vapor Mitigation System Component Map

List of Appendices

Appendix A MVIMS Design Drawings
Appendix B MVIMS Inspection Forms (October 2021 to August 2022)
Appendix C Methane Monitor Specification Sheet
Appendix D Landfill Gas Meter Calibration Logs
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Methane VIMS Inspection and O&M
Brightwalk Development-Phase 8
Charlotte, North Carolina
Brownfields Project No. 11037-07-060
H&H Job No. CHP-041

1.0 Introduction

On behalf of DreamKey Partners, LLC (DreamKey) (formerly Charlotte-Mecklenburg Housing
Partnership), Hart & Hickman, PC (H&H) has prepared this report documenting inspection and
operations & maintenance (O&M) activities conducted on the methane vapor intrusion
mitigation systems (MVIMSs) installed in eight (8) single-family homes in the Brightwalk Phase
8 Development in Charlotte, North Carolina (Site). The Brightwalk Phase 8 development is part
of the Double Oaks Brownfields Project (Brownfields Project No. 11037-01-060). A Site
location map is provided as Figure 1.

The Double Oaks Brownfields property is developed with residential apartments, townhomes,
and single-family homes. The Phase 8 Development includes eight (8) single-family homes
located along Double Oaks Road which is near the former Double Oaks Landfill. The
approximate extent of the former landfill and eight Double Oaks single-family homes are shown
on Figure 2.

The former Double Oaks Landfill is managed in the North Carolina Department of
Environmental Quality (DEQ) Pre-Regulatory Landfill Program (Project No. NONCD0000806).
Previous assessment activities conducted in and around the former Double Oaks landfill
indicated the presence of elevated methane vapor concentrations in soil gas. The Pre-Regulatory
Landfill Program capped the former landfill in 2014.

Due to the proximity of the Phase 8 Development to the former Double Oaks Landfill and the
presence of elevated methane levels in soil gas, Geoscience Group, LLC (Geoscience) prepared
the Methane Vapor Mitigation System Design and Methane Vapor Mitigation Operation and
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Maintenance Plan (MVMP) dated May 26, 2017 for the proposed single-family residential
homes in the Phase 8 Development. The purpose of the MVMP was to mitigate potential
methane vapor intrusion in the homes constructed as part of the Phase 8 Development. The
MVMP was provided to DEQ and subsequently approved by the Brownfields Program in a letter
dated June 12, 2017. The MVIMSs were installed as part of the Phase 8 construction. The
addresses for the single-family homes with MVIMSs include: 2531, 2535, 2539, 2601, 2605,
2609, 2613, and 2617 Double Oaks Road (Double Oaks Homes). The Phase 8 construction was
completed in approximately December 2017/January 2018. Each property consists of a two-story
dwelling and detached garage. The detached garages are located in the rear of the property and
closest to the former Double Oaks Landfill (Figure 2).

As-built drawings or a construction completion report for the MVIMS installation was not
prepared by Geoscience. However, design drawings were included in the approved MVMP.
Design drawings for the approved MVMP prepared by Geoscience are provided in Appendix A.
According to the approved MVMP and design drawings in Appendix A, the primary components
of the MVIMSs include a minimum 4-inch-thick gravel sub-slab base, a single run of sub-slab
corrugated 4-inch diameter PVC piping connecting the home and detached garage, a 15-mil
vapor barrier, radial blower, and PVC exhaust vent stack. MVIMS monitoring equipment
includes a manometer installed on the radial blower, two (2) sub-slab monitoring points installed
in the living area of each home, and indoor methane sensors with audible alarms. Two (2)
methane sensors are installed in each home and one (1) methane sensor is installed in each
garage. The methane sensor is designed with an audible alert that is activated if methane is
detected at 25% of the lower explosive limit (LEL). The methane sensor is also equipped with
an LED screen that flashes red and displays “Gas / Evacuate” when the alarm is activated. The
specification sheet for the methane sensor is provided in Appendix C. Locations of the methane
sensors, MVIMS blower, and sub-slab sample ports are shown on Figure 3.

The approved MVMP also includes requirements for “Initial Performance Testing" (IPT)
following installation of the MVIMS. The IPT described in the MVMP included the collection of
differential pressure readings from the sub-slab sample ports installed in each home and the
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collection of sub-slab and indoor air samples for laboratory analysis of volatile organic
compounds (VOCs) by EPA Method TO-15 and methane by EPA Method 8015M or EPA
Method D1946. The IPT was conducted by Geosciences in December 2017 and January 2018.

Results of Geoscience’s IPT were provided to DEQ in H&H’s Methane VMS Inspection and
O&M Report, Revision 1, dated August 30, 2021 (2021 Methane VMS Inspection Report). In
summary, the results of Geoscience’s IPT indicated the presence of differential pressure below
the slab in each of the homes ranging from -0.85 inches of water column (WIC) to -1.12 WIC.
The differential pressures documented by Geosciences during the IPT exceed the DEQ minimum
sub-slab depressurization requirement of -0.016 WIC. Results of the differential pressure
measurements collected during the IPT indicated that the MVIMS was effective at mitigating
potential vapor intrusion at the time of MVIMS startup.

As indicated above, the IPT conducted by Geosciences in December 2018 and January 2019 also
included the collection of sub-slab soil gas and indoor air samples for VOCs and methane.
Laboratory analytical results of the methane analysis for sub-slab and co-located indoor air
samples collected from the homes did not indicate the presence of methane above laboratory
detection limits. VOCs were detected in the indoor air samples collected. However, as discussed
in H&H’s 2021 Methane VMS Inspection Report, VOC concentrations detected in indoor air did
not correlate with sub-slab vapor data. Further, indoor air constituent concentrations were higher
than sub-slab concentrations or were not detected in sub-slab samples. Because attenuation
occurs between sub-slab and indoor air during structural vapor intrusion, these data suggest an
alternate source for the indoor air compounds during the IPT conducted by Geoscience. As such,
the concentrations detected in the indoor air samples are attributed to background and/or indoor
sources, such as off-gassing building materials in the homes which were new at the time of
sampling.

In accordance with the approved MVMP, routine MVIMS inspections were required following
the IPT. On April 27, 2021, DreamKey was notified by DEQ that a report documenting the
installation of the MVIMS and results of routine inspections had not been received. Accordingly,
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DreamKey contacted H&H to inspect and confirm operation of the MVIMS. On May 14 and 17,
2021, H&H visited each of the Double Oaks Homes and confirmed that the MVIMS fans were
operational and inspected for the presence and functionality of methane monitors inside the
homes and garages.

Following H&H’s MVIMS inspection, DEQ personnel visited the Site on May 21, 2021 to meet
with DreamKey and H&H to observe MVIMS operation in select homes. During the DEQ Site
visit and at DEQ’s request, methane readings were also collected from three landfill gas probes
(LG-23, LG-24, and LG-25) installed along Woodward Avenue (Figure 2). Methane was not
detected above the 5% by volume (100% of the LEL) regulatory threshold for landfill property
boundaries. In addition, methane above 5% was not detected in these three monitoring points in
multiple monitoring events conducted by others in 2017 and 2018.

Results of the MVIMS inspection and DEQ Site visit were provided to DEQ in H&H’s 2021
Methane VMS Inspection Report. The 2021 Methane VMS Inspection Report also included the
following recommendations:

 conduct quarterly MVIMS O&M inspections,
 replace u-tube manometers installed on the MVIMS fans with differential pressure
gauges,
 open the MVIMS cleanout at each home and inspect for the presence of water in the
accessible MVIMS piping, and
 replace the methane sensors with audible alarms installed in each home prior to the end
of their 5-year service life.

The 2021 Methane VMS Inspection Report and associated recommendations were approved by
DEQ in an email dated October 13, 2021. The DEQ approval also included a request to collect
methane and differential pressure readings from the sub-slab sample ports inside the homes as
part of the inspection and O&M activities. The following report describes the results of the
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MVIMS activities conducted at the Site pursuant to H&H’s 2021 recommendations and DEQ’s
requests.
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2.0 MVIMS Inspection and O&M

2.1 MVIMS Status and Data

MVIMS inspections and O&M visits were conducted in October/November 2021, March 2022,
July/August 2022, and November 2022. The MVIMS visits included confirming MVIMS fan
operation, confirming the presence and operation of methane sensors, and the collection of
methane and sub-slab differential pressure readings from sample ports installed in the homes.
Differential pressure readings were collected utilizing a digital manometer capable of detecting
differential pressure equal to or greater than 0.001 WIC and methane readings were collected
utilizing a calibrated Landtec GEM 5000™. Calibration logs for the GEM 5000™ for each
O&M visit are provided in Appendix D.

The u-tube manometers on the systems were replaced with Dwyer Series 2-5005 Minihelic® II
differential pressure gauges during the October/November 2021 visit. Due to aging sensors, a
number of methane sensors in the homes were replaced during the July/August 2022 visit. The
methane sensors in each home now have at least two years remaining on their service life
(Appendix B).

During each Site visit, H&H completed a Methane and Vapor Intrusion Mitigation System
Inspection Form (Inspection Form) for each home. Inspection Forms completed by H&H
personnel during each MVIMS Inspection and O&M event are provided in Appendix B. A
summary of the O&M activities is provided below.

During the October/November 2021 inspection, H&H observed that the MVIMS blowers were
operational for each home and the exhaust vents were unobstructed. MVIMS blower operation
was verified by confirming the presence of a vacuum on the analog manometer installed on each
MVIMS blower. Although the MVIMS blowers were operational during the October/November
2021 Inspection and O&M visit, differential pressure readings collected from the sub-slab
sample ports installed in the homes did not indicate the presence of a differential pressure.
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Although a differential pressure was not present, methane was not detected in the sub-slab
sample ports installed in each home during the October 2021 MVIMS inspection.

To further evaluate the MVIMS system during the October/November 2021 Inspection and
O&M visit, H&H opened accessible sewer style piping cleanouts installed on the sub-slab
depressurization piping between the home and detached garage (Appendix A; Detail 3 Sheet
VM5.0). After opening the cleanout, H&H observed that MVIMS piping was filled with water to
approximately 6-inches below ground surface (bgs). Cleanouts were not accessible in three of the
eight properties in October 2021 (2617 Double Oaks, 2539 Double Oaks, and 2539 Double
Oaks) due to the installation of pavers, landscaping, or prior expansion of the concrete patio by
the homeowner. Because the cleanouts were not accessible, a contractor was subsequently hired
by the homeowner’s association (HOA) to make alterations to extend the sewer cleanouts to the
surface. The alterations and cleanout extensions were completed in February 2022, and water
was also confirmed to be present in MVIMS piping in these three homes following the
alterations. As indicated in the MVIMS design sheets in Appendix A, a low point is present in
the MVIMS piping between the home and garage. The low point accumulates water which
prevents the radial blower from creating a vacuum below the slab of the homes.

Once the cleanouts were accessible, H&H removed the water from the MVIMS piping at each
home on February 28, 2022 utilizing a shop vac. Following removal of the water, H&H
conducted a MVIMS O&M visit at the Site on March 16, 18, and 21, 2022. Although the water
was removed approximately two to three weeks prior to the MVIMS inspections, water had
again accumulated in MVIMS piping, and differential pressure was not observed in the sub-slab
sampling ports installed in the home. The results of the March 2022 Site inspections suggests
that water accumulates in the MVIMS piping over a short period of time.

The water in the MVIMS piping was removed during the March 2022 O&M event and
differential pressure and methane readings were collected from the sub-slab sample ports.
Differential pressure measurements collected from below the slab of the homes following
removal of the water from the MVIMS piping ranged from -0.222 to -2.213 (Appendix B) which
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exceeds the Brownfields Program sub-slab depressurization threshold for vapor intrusion of -
0.016 WIC. Methane was not detected below the slab of the homes during the March 2022
O&M visit.

Because water appears to accumulate in the MVIMS piping over a short period of time and
repeated removal of the water from the piping is not a practical long-term solution, H&H had a
conference call with the Brownfields Program on June 13, 2022 to discuss next steps for the Site.
During the call, it was determined that because methane was not detected below the slab of the
homes when a vacuum is not present, a risk for methane vapor intrusion may not be present and
modifications to the MVIMS may not be warranted. As such, H&H recommended continued
MVIMS inspections with sub-slab methane monitoring and the installation of a sub-slab sample
port in the garage to determine if differential pressure was present below the slab of the garage.
As indicated in the MVIMS design sheets and confirmed in the field by H&H, a sub-slab sample
had not been installed in the garages as part of the MVIMS installation by others.

Following the conference call with the Brownfields Program, a MVIMS Inspection and O&M
visit was subsequently conducted in July/August 2022. During the July/August 2022 Site visit,
differential pressure was not observed below the slab in six of the eight single-family homes
indicating that the MVIMS had filled with water since the March 2022 Site visit. However, the
system piping at homes located at 2539 Double Oaks and 2617 Double Oaks had not filled with
water, and differential pressures were observed below the slabs ranging from -0.700 WIC to -
0.743 WIC (2539 Double Oaks) and -2.241 WIC to -2.266 WIC (2617 Double Oaks). Although
the MVIMS piping was filled with water in six of the eight homes, methane was not detected in
the sub-slab monitoring points installed in the homes during the July/August 2022 MVIMS
activities.

Following the July/August 2022 Site visit, a Site visit was conducted in November 2022. During
the November 2022 Site visit, differential pressure was not observed below the slab in seven of
the eight single-family homes, indicating that the MVIMS piping in only one home (2539
Double Oaks Road) had not filled with water. The sub-slab differential pressure measured from
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the front (-0.643 WIC), rear (-0.670 WIC), and garage (-0.731 WIC) sample ports installed in
2539 Double Oaks exceed the Brownfields sub-slab depressurization goal of -0.016 WIC.
Methane was not detected below the slabs of 2539 Double Oaks Road or the remaining houses
during the November 2022 Site visit. Results of the differential pressure readings collected from
the garage sub-slab sample ports in installed in the eight garages during the November 2022 Site
visit ranged from -0.075 WIC to -2.594 WIC.

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2.2 Subslab Monitoring in Garages

As discussed with the Brownfields Program during the June 2022 conference call, H&H installed
subsurface monitoring points in the slab of the detached garage at each home as part of the
July/August 2022 MVIMS activities. The subsurface monitoring points were installed in the
central portion of the garage slab. Locations of the garage sub-slab sample ports are shown on
Figure 3. The purpose of the subsurface monitoring points was to determine if a vacuum is
present below the garage slab when the MVIMS piping is filled with water and determine if
elevated concentrations of methane were present below the slab of the garage. The garages are
situated between the former landfill and the homes, and the subslab vapor points in the garages
can serve as sentinel monitoring points. The sub-slab sample points were installed by advancing
a boring through the slab utilizing a hammer drill and installing a flush Cox Colvin vapor pin.

Following installation of the garage sub-slab sample ports, a helium leak check was utilized to
determine if leaks were present. The helium leak test was conducted by constructing a shroud
around the sub-slab sample port and saturating the air within the shroud with helium gas. A
sample was then collected from the sub-slab sample port and purged into a Tedlar bag utilizing a
three-way syringe. A helium detector was then utilized to measure for helium inside the Tedlar
bag to confirm that helium concentrations in the bag did not exceed 10% of the helium detected
in the shroud. Results of the leak testing at each sub-slab sample point did not indicate the
presence of helium in the shroud.

Following the successful leak check, a differential pressure reading and a methane reading were
collected from the garage sub-slab sample port. Methane was not detected below the garage
slabs. Differential pressure measurements collected below the garage slab indicate the presence
of differential pressure ranging from -0.680 WIC to -2.455 WIC. Differential pressure and
methane readings collected from below the slab in each garage in July/August 2022 and
November 2022 are provided on the MVIMS forms in Appendix B. Results of the July/August
O&M visit indicate that a differential pressure below the slab of the garage above the
Brownfields Program threshold of -0.016 WIC is present when the MVIMS piping is filled with
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water. As shown in the design drawings in Appendix A, the radial blower is located on the
exterior wall of the garage and is directly connected to the MVIMS depressurization piping
below the garage. Water accumulation in the MVIMS is limited to the low point between the
home and garage. Therefore, the garage portion of the MVIMS is not affected by water
accumulation.

2.3 Pre-Regulatory Landfill Methane Probe Monitoring

As indicated above, H&H collected methane readings from landfill gas probes LG-23, LG-24,
and LG-25 during the MVIMS activities. A summary of the methane readings collected from the
landfill gas probes is provided on Table 1. Consistent with the past three monitoring events,
methane was not detected in the landfill gas probes during the MVIMS activities. As part of the
November 2022 Site visit, static pressure readings were also collected from the landfill gas
probes. Results of the static pressure readings indicated a static pressure of -0.03 WIC (LG-23)
to 0.00 WIC (LG-25) indicating a lower pressure in the subsurface relative to ambient pressure.
Static pressure readings (in conjunction with methane readings) will continue to be collected
from LG-23, LG-24, and LG-25 during future O&M events.

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3.0 Summary and Recommendations

H&H conducted MVIMS Inspections and O&M visits in October/November 2021, March 2022,
and July/August 2022 at the eight (8) single-family homes in the Brightwalk Phase 8
development in Charlotte, North Carolina. The MVIMS inspection and O&M activities
conducted by H&H generally included confirming MVIMS fan operation, confirming the
presence and operation of methane sensors in the homes, and the collection of methane and sub-
slab differential pressure readings from sample ports installed in the homes and garages. As part
of the MVIMS inspection and O&M visits, methane readings were also collected from landfill
gas probes LF-23, LF-24, and LF-25.

During the October 2021 Site visit, differential pressure was not observed at the sub-slab sample
ports installed inside the homes. It was determined by H&H that the MVIMS piping between the
home and detached garage was filled with water due to a low point in the system piping design
prepared by Geoscience Group. The MVIMS piping between the home and detached garage is a
low point in the MVIMS system which accumulates water and prevents the radial blower from
creating a vacuum below the slab of the home.

The water was removed from the MVIMS piping in February 2022. However, the MVIMS
piping was observed to be filled with water during the subsequent March 2022 MVIMS
Inspection and O&M visit. H&H removed the water again in March 2022 and collected
differential pressure readings below the home. Results of the differential pressure readings
collected in March 2022 demonstrated that the MVIMS is effective at creating a negative
pressure below the slab of each home above the Brownfields threshold of -0.016 WIC for vapor
mitigation once the water is removed. However, because water accumulates in the MVIMS
piping over a short period of time, continued water removal is not a practical long-term solution.

On June 13, 2022, H&H had a conference call with the Brownfields Program to discuss MVIMS
operation and next steps for the Site. During the call, it was decided that because methane was
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not detected below the slab of the homes when a vacuum is not present, a risk for methane vapor
intrusion may not be present and modifications to the MVIMS may not be warranted.

To demonstrate that a risk for methane vapor intrusion may not be present in the homes, H&H
recommended continued MVIMS inspections with sub-slab methane monitoring and the
installation of a sub-slab sample port in the garage to determine if differential pressure and/or
methane was present below the slab of the garage. As part of the MVIMS inspection and O&M
visits, methane readings were also collected from landfill gas probes LF-23, LF-24, and LF-25
(Figure 2) utilizing the Landtec GEM 5000™.

A MVIMS Inspection and O&M visit was subsequently conducted in July/August 2022 and
November 2022. During the July/August 2022 Site visit, differential pressure was not observed
below the slab in 6 of the 8 single family homes indicating that the MVIMS piping had filled
with water since the March 2022 Site visit. Consistent with earlier MVIMS O&M Site visits,
although a differential pressure was not present, methane was also not detected below the homes.
Results of the differential pressure readings collected from the sub-slab sample ports installed
inside the garages indicated the presence of a differential pressure ranging from -0.680 WIC to -
2.455 WIC. Methane was not detected below the garage slabs.

During the November 2022 Site visit, differential pressure was not observed below the slab in 7
of the 8 single-family homes indicating that the MVIMS piping in only one home (2539 Double
Oaks Road) had not filled with water. The sub-slab differential pressure measured from the
front, rear, and garage sub-slab sample ports of 2539 Double Oaks exceed the Brownfields sub-
slab depressurization goal of -0.016 WIC.

Methane was not detected below the slab of 2539 Double Oaks Road or the remaining houses
during the November 2022 Site visit. Results of the differential pressure readings collected from
the garage sub-slab sample port during the November 2022 Site visit ranged from -0.075 WIC to
-2.594 WIC

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Recommendation
Based on the absence of methane below the homes or garages in the July/August and November
2022 monitoring events, the risk for methane vapor intrusion is low and modifications to the
MVIMS are not warranted at this time. To further demonstrate that the risk for methane vapor
intrusion is low, H&H recommends quarterly MVIMS O&M visits for a period of one year. The
MVIMS O&M visits will include:

 confirming MVIMS fan operation
 confirming the presence and operation of methane sensors in the home and garage
 collection of differential pressure and methane measurements from the sub-slab sample
ports in the home and garage
 collection of methane measurements from landfill gas probes LG-23, LG-24, and LG-25

Results of the proposed MVIMS O&M visits will be provided to DEQ on a quarterly basis. If
methane is not detected above the DEQ threshold of 1.25% for methane in buildings in the sub-
slab monitoring points during the 1-year monitoring period, the MVIMS Inspections and O&M
visits will be reduced to a semi-annual basis.

In addition, and per DEQ’s request, H&H will collect sub-slab samples from a representative
number of homes to evaluate for the presence of VOCs. The sub-slab samples will be collected
from the rear sub-slab sample port in a minimum of four of the eight single-family homes. The
option to collect sub-slab samples from remaining homes will be offered to the homeowners.
The sub-slab samples will be submitted for laboratory analysis of VOCs by EPA Method TO-15.
If the results of the sub-slab sampling indicate the potential for vapor intrusion above DEQ Risk
Thresholds, indoor air sampling will be conducted and modifications to the MVIMS may be
needed.
Table

Table 1
Summary of Landfill Gas Probe Data
Brightwalk Phase 8 Development
Charlotte, North Carolina
H&H Project No. CHP-041
Sample ID Sample Date CH4 (%)CO2 (%)O2 (%)CO (ppm)H2S (ppm)Static Pressure
(in. H2O)
5/21/2021 0.0 5.7 11.6 NM NM NM
10/1/21 0.0 4.4 9.2 NM NM NM
3/1/22 0.0 3.8 8.8 NM NM NM
7/25/22 0.0 9.4 10.7 NM NM NM
11/18/2022*0.0 1.8 20.0 0.0 0.0 -0.03
5/21/21 0.0 9.4 10.5 NM NM NM
10/1/21 0.0 10.1 10.8 NM NM NM
3/1/22 0.0 11.3 11.1 NM NM NM
7/25/22 0.0 15.3 6.2 NM NM NM
11/16/22 0.0 11.1 10.5 0.0 0.0 -0.01
5/21/21 0.0 10.8 2.9 NM NM NM
10/1/21 0.0 11.8 3.1 NM NM NM
3/1/22 0.0 12.2 3.2 NM NM NM
7/25/22 0.0 14.9 3.4 NM NM NM
11/16/22 0.0 14.8 7.4 0.0 0.0 0.00
Notes:
Landfilll gas probes installed by URS in August 2015
The North Carolina Landfill Gas Monitoring Regulation is 5% methane (100% LEL) at the landfill property line.
*Water was removed from LG-23 on November 16, 2022 and sampled on November 18, 2022.
Measurements were collected by H&H using a calibrated LANDTEC GEM 5000
Negative static pressure values indicate that subsurface pressure is lower than ambient air pressure
CH4 = methane; O2 = oxygen; CO2 = carbon dioxide; CO = carbon monoxide; H2S = hydrogen sulfide;
in H₂O = inches of water; % = percent by volume of air; ppm = parts per million; NM = not measured
LG-25
LG-24
LG-23
S:\AAA-Master Projects\Charlotte Mecklenburg Housing Partnership - CHP\CHP-041 Double Oaks Methane\Report\Aug-22
Table 1 (Page 1 of 1)
Hart & Hickman, PC
Figures

0 2000 4000
APPROXIMATE
SCALE IN FEET
N
U.S.G.S. QUADRANGLE MAP
QUADRANGLE
7.5 MINUTE SERIES (TOPOGRAPHIC)
NORTH: DERITA, NC 1996
SOUTH: CHARLOTTE EAST, NC 1991
TITLE
PROJECT
SITE LOCATION MAP
BRIGHTWALK PHASE 8
BROWNFIELDS PROJECT 11037-01-060
CHARLOTTE, NORTH CAROLINA
DATE:
JOB NO:
REVISION NO:
FIGURE:
06-04-2021 0
1CHP-041
SITE
LG-24
LG-23
LG-25
REVISION NO. 0
JOB NO. CHP-041
DATE: 12-8-22
FIGURE NO. 2
DREAMKEY PARTNERS BRIGHTWALK PHASE 8
DOUBLE OAKS ROAD
CHARLOTTE, NORTH CAROLINA
SITE MAP
LEGEND
PARCEL BOUNDARY
LANDFILL GAS PROBE
BRIGHTWALK PHASE 8 DEVELOPMENT
PROPERTY ID
2923 South Tryon Street-Suite 100
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f)
License # C-1269 / #C-245 Geology
NOTES:
1.AERIAL IMAGERY OBTAINED FROM MECKLENBURG
COUNTY GIS (2022).IRWIN CREEKINTERSTATE-77DOUBLE OAKS ROADMOSS LANEWO
O
D
W
A
R
D

A
V
E
N
U
E
MOS
S

L
A
N
E
CLOSED/CAPPED
LANDFILL AREA
PROPERTY ID ADDRESS
1 2531 DOUBLE OAKS ROAD
2 2535 DOUBLE OAKS ROAD
3 2539 DOUBLE OAKS ROAD
4 2601 DOUBLE OAKS ROAD
5 2605 DOUBLE OAKS ROAD
6 2609 DOUBLE OAKS ROAD
7 2613 DOUBLE OAKS ROAD
8 2617 DOUBLE OAKS ROAD
S:\AAA-Master Projects\Charlotte Mecklenburg Housing Partnership - CHP\CHP-041 Double Oaks Methane\Report\2022 MVIMS O&M Report\Figures\CHP.041_20221208.dwg, FIG 2, 12/8/2022 10:00:50 AM, shaynes
REVISION NO. 0
JOB NO. CHP-041
DATE: 12-8-22
FIGURE NO. 3
DREAMKEY PARTNERS BRIGHTWALK PHASE 8
DOUBLE OAKS ROAD
CHARLOTTE, NORTH CAROLINA
METHANE VAPOR MITIGATION
SYSTEM COMPONENT MAP
LEGEND
PARCEL BOUNDARY
BRIGHTWALK PHASE 8 DEVELOPMENT
PROPERTY ID
SUB-SLAB SAMPLE PORT
UPPER LEVEL METHANE SENSOR
LOWER LEVEL METHANE SENSOR
METHANE VAPOR MITIGATION FAN
AND EXHAUST
2923 South Tryon Street-Suite 100
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f)
License # C-1269 / #C-245 Geology
NOTES:
1.AERIAL IMAGERY OBTAINED FROM MECKLENBURG
COUNTY GIS (2022).DOUBLE OAKS ROADMOSS LANEMOS
S

L
A
N
E
CLOSED/CAPPED
LANDFILL AREA
PROPERTY ID ADDRESS
1 2531 DOUBLE OAKS ROAD
2 2535 DOUBLE OAKS ROAD
3 2539 DOUBLE OAKS ROAD
4 2601 DOUBLE OAKS ROAD
5 2605 DOUBLE OAKS ROAD
6 2609 DOUBLE OAKS ROAD
7 2613 DOUBLE OAKS ROAD
8 2617 DOUBLE OAKS ROAD
S:\AAA-Master Projects\Charlotte Mecklenburg Housing Partnership - CHP\CHP-041 Double Oaks Methane\Report\2022 MVIMS O&M Report\Figures\CHP.041_20221208.dwg, FIG 3, 12/8/2022 10:03:39 AM, shaynes
Appendix A
MVIMS Design Drawings

F-0585
500-K Clanton Road
Charlotte, NC 28217
Phone: [phone]
Fax: [phone]
www.geosciencegroup.comP:\Work Files\ENV\2015\014 -Brightwalk\CAD\all fslab plans6.2.17.dwg, 6/13/2017 11:08:09 AM, 1:1
F-0585
500-K Clanton Road
Charlotte, NC 28217
Phone: [phone]
Fax: [phone]
www.geosciencegroup.comP:\Work Files\ENV\2015\014 -Brightwalk\CAD\all fslab plans6.2.17.dwg, 6/13/2017 11:34:58 AM, 1:1
F-0585
500-K Clanton Road
Charlotte, NC 28217
Phone: [phone]
Fax: [phone]
www.geosciencegroup.comP:\Work Files\ENV\2015\014 -Brightwalk\CAD\all fslab plans6.2.17.dwg, 6/13/2017 11:33:17 AM, 1:1
F-0585500-K Clanton RoadCharlotte, NC 28217Phone: [phone]Fax: [phone]www.geosciencegroup.comP:\Work Files\ENV\2015\014 -Brightwalk\CAD\fslab Garages6.2.17.dwg, 6/13/2017 11:31:00 AM, 1:1
F-0585500-K Clanton RoadCharlotte, NC 28217Phone: [phone]Fax: [phone]www.geosciencegroup.comP:\Work Files\ENV\2015\014 -Brightwalk\CAD\6.2.17Details.dwg, 6/13/2017 11:29:05 AM, 1:1
Appendix B
MVIMS Inspection Forms (October 2021 to August 2022)

Inspection Date and Time _______________________
HouseAddress_________________________________
H&HPersonel__________________________________
Isthesystemoperationalonarrival?(Yes/No)
SystemDifferentialPressure__________"H2O
Isdischargepiping(exhaust)visiblyobstructed?(Yes/No)
Aretherevisiblegapsorcracksintheslabpresentinaccessibleareasofthegroundfloor?(Yes/No)
Ifyes,describe_________________________________________________________________________
_______________________________________________________________________________________
MethaneDetectors:
Detector1:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector2:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector3:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
MethaneandDifferentialPressureReadings:
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
IndoorsDownstairs:
IndoorsUpstairs:
GaragĞ:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
SubͲslabPort(Front)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Anyrepairsormodificationstothehomeorgaragesincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Doesthehomeowner/occupantreportanymethanealarmssincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Notes:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
MVMSInspectionForm
DoubleOaksBrownfieldsSite(BrownfieldsNo.11037Ͳ07Ͳ60)
BrightwalksPhase8
DoubleOaksRoadCharlotte,NC
H&HJobNo.CHP.041
S:\AAAͲMasterProjects\CharlotteMecklenburgHousingPartnershipͲCHP\CHPͲ041DoubleOaksMethane\MVIMSO Hart Hickman, PC
SubͲslabPort(Rear)
Sub-slab Port ('ĂƌĂŐĞ)CH4:______ O2:_______CO:_______H2S:_______CO2:_______Bal:_______Diff:ͲϮ͘ϱϵϰ
Yes /
/No)
/No)
(Yes/
(Yes/
(Yes/
11/17/22 @ 0930
2531 Double Oaks Road
JSH
2.8
Front Hallway Apr 2021
Upstairs Behind Couch Dec 2021
Garage Apr 2022
0.0 21.2 0 00.278.6
0.0 21.2 1 00.178.7
0.0 21.4 1 00.178.5
0.0 21.2 0 00.278.6 0.003
0.0 19.9 0 00.679.5 0.046
No
No
Inspection Date and Time _______________________
HouseAddress_________________________________
H&HPersonel__________________________________
Isthesystemoperationalonarrival?(Yes/No)
SystemDifferentialPressure__________"H2O
Isdischargepiping(exhaust)visiblyobstructed?(Yes/No)
Aretherevisiblegapsorcracksintheslabpresentinaccessibleareasofthegroundfloor?(Yes/No)
Ifyes,describe_________________________________________________________________________
_______________________________________________________________________________________
MethaneDetectors:
Detector1:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector2:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector3:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
MethaneandDifferentialPressureReadings:
IndoorsDownstairs:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
IndoorsUpstairs:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
Garage:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
SubͲslabPort(Front)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
SubͲslabPort(Rear)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Anyrepairsormodificationstothehomeorgaragesincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Doesthehomeowner/occupantreportanymethanealarmssincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Notes:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
MVMSInspectionForm
DoubleOaksBrownfieldsSite(BrownfieldsNo.11037Ͳ07Ͳ60)
BrightwalksPhase8
DoubleOaksRoadCharlotte,NC
H&HJobNo.CHP.041
S:\AAAͲMasterProjects\CharlotteMecklenburgHousingPartnershipͲCHP\CHPͲ041DoubleOaksMethane\MVIMSO Hart Hickman, PC
O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______

(Yes /
/No)
(Yes/
(Yes/
(Yes/
Sub-slab Port (Garage) CH4 :______
11/16/22 @ 0945
2535 Double Oaks Road
JSH
0.8
Kitchen June 2022
Upstairs Hall Dec 2021
Garage June 2022
0.0 21.3 0 00.178.6
0.0 21.4 0 00.178.5
0.0 21.4 0 00.178.5
0.0 21.1 0 00.478.5 0.000
0.0 21.0 0 00.478.7 0.000
No
No
Gas range in kitchen
Inspection Date and Time _______________________
HouseAddress_________________________________
H&HPersonel__________________________________
Isthesystemoperationalonarrival?(Yes/No)
SystemDifferentialPressure__________"H2O
Isdischargepiping(exhaust)visiblyobstructed?(Yes/No)
Aretherevisiblegapsorcracksintheslabpresentinaccessibleareasofthegroundfloor?(Yes/No)
Ifyes,describe_________________________________________________________________________
_______________________________________________________________________________________
MethaneDetectors:
Detector1:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector2:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector3:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
MethaneandDifferentialPressureReadings:
IndoorsDownstairs:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
IndoorsUpstairs:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
Garage:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
SubͲslabPort(Front)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Anyrepairsormodificationstothehomeorgaragesincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Doesthehomeowner/occupantreportanymethanealarmssincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Notes:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
MVMSInspectionForm
DoubleOaksBrownfieldsSite(BrownfieldsNo.11037Ͳ07Ͳ60)
BrightwalksPhase8
DoubleOaksRoadCharlotte,NC
H&HJobNo.CHP.041
S:\AAAͲMasterProjects\CharlotteMecklenburgHousingPartnershipͲCHP\CHPͲ041DoubleOaksMethane\MVIMSO Hart Hickman, PC
SubͲslabPort(Rear)
Sub-Slab Port (Garage)CH4:______O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______

Yes /
/No)
/No)
(Yes/
(Yes/
(Yes/
11/28/22 @ 0940
2539 Double Oaks Road
JSH
0.6
Kitchen Jan 2021
Upstairs Hallway* April 2022
Garage Jan 2021
0.0 21.0 1 00.178.8
0.0 21.2 0 00.078.7
0.0 21.3 0 00.178.7
0.0 21.1 0 00.178.8 -0.643
0.0 21.1 0 00.178.8 -0.670
No
No
*Methane Sensor (Detector 2) in upstairs hallway missing during November 28, 2022 O&M visit.
Detector 2 replaced on November 29, 2022. Manufacturer date April 2022.
Inspection Date and Time _______________________
HouseAddress_________________________________
H&HPersonel__________________________________
Isthesystemoperationalonarrival?(Yes/No)
SystemDifferentialPressure__________"H2O
Isdischargepiping(exhaust)visiblyobstructed?(Yes/No)
Aretherevisiblegapsorcracksintheslabpresentinaccessibleareasofthegroundfloor?(Yes/No)
Ifyes,describe_________________________________________________________________________
_______________________________________________________________________________________
MethaneDetectors:
Detector1:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector2:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector3:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
MethaneandDifferentialPressureReadings:
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
IndoorsDownstairs:
IndoorsUpstairs:
Garage:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
SubͲslabPort(Front)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
SubͲslabPort(Rear)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Anyrepairsormodificationstothehomeorgaragesincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Doesthehomeowner/occupantreportanymethanealarmssincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Notes:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
MVMSInspectionForm
DoubleOaksBrownfieldsSite(BrownfieldsNo.11037Ͳ07Ͳ60)
BrightwalksPhase8
DoubleOaksRoadCharlotte,NC
H&HJobNo.CHP.041
S:\AAAͲMasterProjects\CharlotteMecklenburgHousingPartnershipͲCHP\CHPͲ041DoubleOaksMethane\MVIMSO Hart Hickman, PC
Sub-slab Port (Garage)CH4:______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______O2 19:_____
Yes /
/No)
/No)
(Yes/
(Yes/
(Yes/
11/17/22 @ 1130
2601 Double Oaks Road
JSH
2.3
Front Hall Behind Bench March 2022
Upstairs hall March 2022
Garage Behind Shelf Jan 2021
0.0 20.8 0.1 0079.1
0.0 21.2 0 00.178.7
0.0 21.5 0 00.178.0
0.0 20.2 0 00.579.5 0.007
0.0 20.0 0 00.679.5 0.010
No
No
Gas stove in kitchen
Inspection Date and Time _______________________
HouseAddress_________________________________
H&HPersonel__________________________________
Isthesystemoperationalonarrival?(Yes/No)
SystemDifferentialPressure__________"H2O
Isdischargepiping(exhaust)visiblyobstructed?(Yes/No)
Aretherevisiblegapsorcracksintheslabpresentinaccessibleareasofthegroundfloor?(Yes/No)
Ifyes,describe_________________________________________________________________________
_______________________________________________________________________________________
MethaneDetectors:
Detector1:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector2:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector3:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
MethaneandDifferentialPressureReadings:
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
IndoorsDownstairs:
IndoorsUpstairs:
GaragĞ:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
SubͲslabPort(Front)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
CH4:______O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Anyrepairsormodificationstothehomeorgaragesincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Doesthehomeowner/occupantreportanymethanealarmssincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Notes:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
MVMSInspectionForm
DoubleOaksBrownfieldsSite(BrownfieldsNo.11037Ͳ07Ͳ60)
BrightwalksPhase8
DoubleOaksRoadCharlotte,NC
H&HJobNo.CHP.041
S:\AAAͲMasterProjects\CharlotteMecklenburgHousingPartnershipͲCHP\CHPͲ041DoubleOaksMethane\MVIMSO Hart Hickman, PC
SubͲslabPort(Rear)
Sub-Slab Port (Garage) CH4:______O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______

Yes /
/No)
(Yes/
(Yes/
(Yes/
/No)
11/29/22 @ 1400
2605 Double Oaks Road
JSH
1.4
Kitchen Island March 2020
Upstairs Hallway March 2020
Garage* Feb 2022
0.0 21.2 0 00.178.7
0.0 21.2 0 00.178.7
0.0 21.2 0 00.178.7
0.0 20.8 0 10.279.0 0.005
0.0 20.8 0 00.179.1 0.003
No
No
*Replaced battery in detector 3
Gas kitchen range
Inspection Date and Time _______________________
HouseAddress_________________________________
H&HPersonel__________________________________
Isthesystemoperationalonarrival?(Yes/No)
SystemDifferentialPressure__________"H2O
Isdischargepiping(exhaust)visiblyobstructed?(Yes/No)
Aretherevisiblegapsorcracksintheslabpresentinaccessibleareasofthegroundfloor?(Yes/No)
Ifyes,describe_________________________________________________________________________
_______________________________________________________________________________________
MethaneDetectors:
Detector1:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector2:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector3:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
MethaneandDifferentialPressureReadings:
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
IndoorsDownstairs:
IndoorsUpstairs:
GaragĞ:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
SubͲslabPort(Front)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
CH4:______O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Anyrepairsormodificationstothehomeorgaragesincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Doesthehomeowner/occupantreportanymethanealarmssincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Notes:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
MVMSInspectionForm
DoubleOaksBrownfieldsSite(BrownfieldsNo.11037Ͳ07Ͳ60)
BrightwalksPhase8
DoubleOaksRoadCharlotte,NC
H&HJobNo.CHP.041
S:\AAAͲMasterProjects\CharlotteMecklenburgHousingPartnershipͲCHP\CHPͲ041DoubleOaksMethane\MVIMSO Hart Hickman, PC
SubͲslabPort(Rear)
Sub-slab Port (Garage)CH4:______O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Yes /
/No)
(Yes/
(Yes/
(Yes/
11/18/22 @ 0930
2609 Double Oaks Road
JSH
1.0
Kitchen April 2022
Upstairs Feb 2021
Garage Dec 2021
0.0 20.8 0 00.179.1
0.0 21.1 1 00.178.8
0.0 21.3 1 00.178.6
0.0 20.8 0 00.179.1 0.006
0.0 21.0 0 00.178.9 0.005
No
No
Gas range
Inspection Date and Time _______________________
HouseAddress_________________________________
H&HPersonel__________________________________
Isthesystemoperationalonarrival?(Yes/No)
SystemDifferentialPressure__________"H2O
Isdischargepiping(exhaust)visiblyobstructed?(Yes/No)
Aretherevisiblegapsorcracksintheslabpresentinaccessibleareasofthegroundfloor?(Yes/No)
Ifyes,describe_________________________________________________________________________
_______________________________________________________________________________________
MethaneDetectors:
Detector1:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector2:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector3:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
MethaneandDifferentialPressureReadings:
IndoorsDownstairs:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
IndoorsUpstairs:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
Garage:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
SubͲslabPort(Front)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
SubͲslabPort(Rear)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Anyrepairsormodificationstothehomeorgaragesincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Doesthehomeowner/occupantreportanymethanealarmssincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Notes:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
MVMSInspectionForm
DoubleOaksBrownfieldsSite(BrownfieldsNo.11037Ͳ07Ͳ60)
BrightwalksPhase8
DoubleOaksRoadCharlotte,NC
H&HJobNo.CHP.041
S:\AAAͲMasterProjects\CharlotteMecklenburgHousingPartnershipͲCHP\CHPͲ041DoubleOaksMethane\MVIMSO Hart Hickman, PC
Sub-slab Port (Garage)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
(Y
/No)
(Yes/
(Yes/
(Yes/
11/18/22 @ 1045
2613 Double Oaks Road
JSH
1.0
Living Room* Apr 2022
2nd Level Behind Couch Mar 2022
Garage Apr 2022
0.0 21.7 1 00.178.2
0.0 21.5 1 00.178.4
0.0 21.7 1 00.178.2
0.0 21.6 0 00.278.2 0.000
0.0 21.3 0 00.278.5 0.000
No
No
*Battery backup replaced
Gas Range
Inspection Date and Time _______________________
HouseAddress_________________________________
H&HPersonel__________________________________
Isthesystemoperationalonarrival?(Yes/No)
SystemDifferentialPressure__________"H2O
Isdischargepiping(exhaust)visiblyobstructed?(Yes/No)
Aretherevisiblegapsorcracksintheslabpresentinaccessibleareasofthegroundfloor?(Yes/No)
Ifyes,describe_________________________________________________________________________
_______________________________________________________________________________________
MethaneDetectors:
Detector1:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector2:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
Detector3:Location:_______________;Functioning?(Yes/No)Manufacturedate_____________
MethaneandDifferentialPressureReadings:
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
IndoorsDownstairs:
IndoorsUpstairs:
GaragĞ:CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______
SubͲslabPort(Front)CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
CH4:______O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
Anyrepairsormodificationstothehomeorgaragesincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Doesthehomeowner/occupantreportanymethanealarmssincelastvisit?
_________________________________________________________________________________________
_________________________________________________________________________________________
Notes:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
MVMSInspectionForm
DoubleOaksBrownfieldsSite(BrownfieldsNo.11037Ͳ07Ͳ60)
BrightwalksPhase8
DoubleOaksRoadCharlotte,NC
H&HJobNo.CHP.041
S:\AAAͲMasterProjects\CharlotteMecklenburgHousingPartnershipͲCHP\CHPͲ041DoubleOaksMethane\MVIMSO Hart Hickman, PC
SubͲslabPort(Rear)
'ĂƌĂŐĞ^^CH4:______ O2:_______CO:_______H2S:_______ CO2:_______Bal:_______ Diff:_______
  
Yes /
/No)
(Yes/
(Yes/
(Yes/
11/18/22 @ 1200
2617 Double Oaks Road
JSH
4.4
Front Hall by SS Port Feb 2022
Upstairs July 2021
*Garage Mar 2022
0.0 21.9 1 00.178.0
0.0 21.5 2 00.178.4
0.0 21.8 0 00.178.1
0.0 21.4 0 00.478.2 0.000
0.0 21.3 0 00.278.5 0.000
No
No
Gas range
*Sensor unplugged upon arrival. Battery replaced and sensor plugged back in.
Appendix C
Methane Monitor Specification Sheet

1 2 3 4 5 6
Printed in Mexico M08-0123-013 K1 5/16
© 2016 BRK Brands, Inc. All rights reserved. Distributed by BRK Brands, Inc. • First Alert® is registered trademark of The First Alert Trust 3901 Liberty Street Road, Aurora, IL 60504-8122 Consumer Affairs: [phone] • www.firstalert.com • www.brkelectronics.com
BASIC SAFETY INFORMATION
• Dangers, Warnings, and Cautions alert you to important operating instructions
or to potentially hazardous situatons. Pay special attention to these items.
• This combination Explosive Gas/Carbon Monoxide Alarm has two separate alarms. The CO Alarm is not designed to detect fire or any other gas. It will only indicate the presence of carbon monoxide gas at the sensor. Carbon monoxide gas may be present in other areas. The Explosive Gas Alarm will only indicate the presence of explosive gas that reaches the sensor. The Explosive Gas Alarm is not designed to sense smoke, heat or flames.
• Do not stand too close to the unit when the alarm is sounding. It is loud to wake you in an emergency. Exposure to the horn at close range may harm your hearing.
• Do not paint over the unit. Paint may clog the openings to the sensing chambers and prevent the unit from operating properly.
• This unit must be powered by a 24-hour circuit. Be sure the circuit cannot be turned off by a switch, dimmer, or ground fault circuit interrupter. Failure to connect this unit to a 24-hour circuit may prevent it from providing constant protection.
• This Alarm must have AC or battery power to operate. If AC power fails and the battery is dead or missing, the alarm cannot operate.
• The Alarm will check for the presence of explosive gas at the sensor less frequently when powered by the back-up battery. Explosive gas could be present during the period between checks without going into alarm, especially during a condition that results in a rapid buildup of explosive gas.
• Test the Alarm once a week. If the Alarm ever fails to test correctly, have it replaced immediately! If the Alarm is not working properly, it cannot alert you to a problem.
• This combination Carbon Monoxide and Explosive Gas Alarm is
intended for residential use and is not suitable for use in hazardous
locations as defined in the National Electrical Code.
• This product is intended for use in ordinary indoor locations of family living units. It is not designed to measure CO levels in compliance with Occupational Safety and Health Administration (OSHA) commercial or industrial standards. Individuals with medical conditions that may make them more sensitive to carbon monoxide may consider using warning devices which provide audible and visual signals for carbon monoxide concentrations under 30 ppm. For additional information on carbon monoxide and your medical condition contact your physician.
FCC Compliance
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that the interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that of the receiver.
• Consult the dealer or an experienced radio or TV technician for help.
Warning: Changes or modifications to the product, not expressly approved by First Alert / BRK Brands, Inc., could void the user’s authority to operate the equipment.
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two
conditions: (1) this device may not cause harmful interference, and (2) this device must accept
any interference received, including interference that may cause undesired operation.
PLUG-IN EXPLOSIVE GAS AND CARBON MONOXIDE ALARM
WITH BATTERY BACK-UP AND SILENCE FEATURE
USER’S MANUAL
INSTALLATION
WHERE TO INSTALL THIS ALARM
For Gas Alarms, mounting depends on the type of explosive gas you intend to detect.
Natural Gas (methane) is typically supplied through a main utility line connected to your home. If you do not live in a rural area you are likely to be a user of natural gas. Natural gas is a fossil fuel consisting mainly of Methane. Methane is much lighter than air and will rise rapidly in air. If you are a user of natural gas, the Alarm should be mounted between 6 and 12 inches (152mm and 305 mm) away from the ceiling (using cord feature) to ensure the earliest opportunity to detect a leak.
Propane is typically supplied to homes by delivery truck in liquid form and stored near the home in propane tanks. Propane is used by homes in rural areas that do not have natural gas
service. Since propane is the most commonly used Liquefied Petroleum Gas (LPG), propane and LP-Gas are often used synonymously. Unlike natural gas, propane is heavier than air and will collect at lower levels. If you are a user of propane, the Alarm should be mounted near the floor (using the direct plug-in feature) to ensure the earliest opportunity to detect a leak.
Both propane and natural gas are colorless and odorless. For safety reasons, an ordorant (Mercaptan) is added so that any leak can be detected by smell. The common detection threshold for smelling the gases is around 20% of the Lower Explosion Limit (LEL). This can vary greatly depending on the individuals sense of smell and how long they have been exposed to it. The LEL of each of these gases defines the bottom range of flammability for the gas. Your Alarm is calibrated to sound before 25% of the LEL of either gas detected.
Therefore, it is possible that you may smell gas before the Alarm is activated. If you are not sure which gas your home uses, contact your utility company.
For CO Alarms, the National Fire Protection Association (NFPA) recommends that
a CO Alarm should be centrally located outside of each separate sleeping area in
the immediate vicinity of the bedrooms. For added protection, install additional
CO Alarms in each separate bedroom, and on every level of your home.
In general, install combination Explosive Gas and Carbon Monoxide Alarms:
• WHERE YOU CAN HEAR THE ALARM FROM ALL SLEEPING AREAS
• In or near bedrooms and living areas or wherever you suspect a gas or CO exposure is likely.
• On each level of a multi-level home.

Improper location can affect the sensitive electronic components in this Alarm. Please see “Where this Alarm Should Not Be Installed”.
Recommended Placement
DINING ROOM KITCHEN BEDROOM BEDROOM
BEDROOMLIVING ROOM
See “Avoiding Dead Air Spaces” for more information.
NOTE: For any location, make sure no door or other obstruction could keep carbon monoxide or gas from reaching the Alarm.
This unit should receive continuous electrical power. (The battery is meant for emergency back-up only). Choose an outlet where it can’t be accidentally unplugged or switched off by children. Keep small children away from the unit. Teach them not to play with it or unplug it. Explain what the alarms mean.
120VAC ~ 60Hz, 0.25 A
IMPORTANT! PLEASE READ CAREFULLY AND SAVE.
This user’s manual contains important information about your Smoke Alarm’s operation. If you are installing this Smoke Alarm for use by others, you must leave this manual—or a copy of it—with the end user.
Model GC01CONFORMS TO UL STD
1484 and UL STD 2034
Printed in Mexico
M08-0123-013 K1 5/16
3.875 inches
3.875 inchesMounting Guide Template
3 7/8 inches (98mm)
WHAT TO DO IF EXPLOSIVE GAS IS DETECTED
If you hear the alarm horn sound one beep per second, gas has been detected. The word GAS will be displayed. Evacuate everyone from the building.
1. Leave the house immediately, opening doors and windows as you leave.
2. Do not use your telephone or appliances. Do not turn any light switches off or on. Any spark or flame could ignite the gas.
3. Call 911 and your gas company from a phone that is away from your home.
4. Do not re-enter the area until the source of the leak is found and corrected.
• If the unit alarms and you are not testing the unit, it is warning you of a potentially dangerous situation that requires your immediate attention. NEVER ignore any alarm. Ignoring the alarm may result in injury or death.
• Never disconnect the power to quiet an unwanted alarm. Disconnecting
the power disables the Alarm. This will remove your protection.
Alarms have various limitations. See “General Limitations of Explosive Gas/CO Alarms” for details.
IF THE CO ALARM SOUNDS:
1. Operate the Test/Silence button.
2. Call your emergency services, fire department or 911. Write down the number of your local emergency service here: _______________________________________________________________
3. Immediately move to fresh air—outdoors or by an open door or window. Do a head count to check that all persons are accounted for. Do not re-enter the premises, or move away from the open door or window until the emergency services responder has arrived, the premises have been aired out, and your CO Alarm remains in its normal condition.
4. After following steps 1-3, if your CO Alarm reactivates within a 24-hour period, repeat steps 1-3 and call a qualified appliance technician to investigate for sources of CO from fuel-burning equipment and appliances, and inspect for proper operation of this equipment. If problems are identified during this inspection have the equipment serviced immediately. Note any combustion equipment not inspected by the technician, and consult the manufacturers’ instructions, or contact the manufacturers directly, for more information about CO safety and this equipment. Make sure that motor vehicles are not, and have not, been operating in an attached garage or adjacent to the residence. Write down the number of a qualified appliance technician here: _______________________________________________________________
IF YOUR GAS/CO ALARM SOUNDS
WHAT TO DO IF CARBON MONOXIDE IS DETECTED
Actuation of your CO Alarm indicates the presence of carbon monoxide (CO) which can kill you. In other words, when your CO Alarm sounds, you must not ignore it!
USING THE SILENCE FEATURES
NEVER disconnect the power to your Alarm to silence the horn—use the Silence Feature. Disconnecting the Alarm removes your protection!
• The Silence Feature is intended to temporarily silence the horn
while you identify and correct the problem.
• To use the Silence Feature, press the Test/Silence button until the horn is silent.
• If the Test/Silence button is pressed while the Alarm is in the silence mode, the alarm will start sounding again.
When the GAS Alarm is silenced...
The Alarm will remain silent for approximately 2 minutes and then return to normal operation. If the gas has not cleared within the silence period, the unit will go back into alarm.
When the CO Alarm is silenced...
The CO Alarm will remain silent for up to 4 minutes. While the Alarm is silenced, it will continue to monitor the air for CO. After 4 minutes, if CO levels remain potentially dangerous the horn will start sounding again.
The Silence Feature is intended to temporarily silence the Alarm horn. It will not correct a CO or gas problem.
SILENCING THE LOW BATTERY WARNING
This Silence Feature can temporarily quiet the low battery warning “chirp” for up to 8 hours if AC
power is present. You can silence the low battery warning “chirp” by pressing the Test/Silence
button on the Alarm cover until you see the Green LED flicker, acknowledging the button-press.
The display will flash “SILENCE” for 8 hours while the low battery warning “chirp” silence feature is activated. After 8 hours, the low battery “chirp” will resume. The
Alarm will continue to operate as long as AC power is supplied. However, replace the
battery as soon as possible, to maintain protection in event of a power outage.
USING THE PEAK CO MEMORYThe CO Memory Feature lets you check the highest level of CO recorded.
To check CO Memory:
1. Press the Display button until the peak CO level is displayed.
To clear CO Memory:
1. Automatically resets after 24 hours.
2. a. While checking CO memory, press or hold the Display button until “CLEAR” is displayed. b. Press or hold the Display button until the CO Memory is cleared.
3. Remove all power; unplug the Alarm and remove the battery.
NOTE: The highest CO level will be saved for 24 hours. DO NOT clear the CO Memory reading if you plan to call someone to investigate a CO problem! Clear the CO Memory reading only after the investigator has checked your home. If the investigator will not arrive within the 24 hour time period before the unit automatically resets, be sure to write down the peak level.
SILENCING THE END OF LIFE SIGNAL
This silence feature can temporarily quiet the End of Life warning “chirp” for up to 2 days.
You can silence the End of Life warning “chirp” by pressing the Test/Silence button. The
horn will chirp, acknowledging that the End of Life silence feature has been activated.
After approximately 2 days, the End of Life “chirp” will resume.
POTENTIAL SOURCES OF CO IN THE HOME
Fuel-burning appliances like: portable heater, gas or wood burning
fireplace, gas kitchen range or cooktop, gas clothes dryer.
Damaged or insufficient venting: corroded or disconnected water heater vent pipe, leaking chimney pipe or flue, or cracked heat exchanger, blocked or clogged chimney opening.
Improper use of appliance/ device: operating a barbecue grill or vehicle in an enclosed area (like a garage or screened porch).
Transient CO Problems: “transient” or on-again-off-again CO problems can
be caused by outdoor conditions and other special circumstances.
The following conditions can result in transient CO situations:
1. Excessive spillage or reverse venting of fuel appliances caused by outdoor conditions such as:
• Wind direction and/or velocity, including high, gusty winds. Heavy air in the vent pipes (cold/humid air with extended periods between cycles).
• Negative pressure differential resulting from the use of exhaust fans.
• Several appliances running at the same time competing for limited fresh air.
• Vent pipe connections vibrating loose from clothes dryers, furnaces, or water heaters.
• Obstructions in or unconventional vent pipe designs
which can amplify the above situations.
2. Extended operation of unvented fuel burning devices (range, oven, fireplace).
3. Temperature inversions, which can trap exhaust close to the ground.
4. Car idling in an open or closed attached garage, or near a home.
These conditions are dangerous because they can trap exhaust in your home. Since these
conditions can come and go, they are also hard to recreate during a CO investigation.
HOW CAN I PROTECT MY FAMILY FROM CO POISONING?A Gas/CO Alarm is an excellent means of protection. It monitors the air and sounds a loud alarm before Carbon Monoxide levels become threatening for average, healthy adults.
A Gas/CO Alarm is not a substitute for proper maintenance of home appliances.
To help prevent CO problems and reduce the risk of CO poisoning:
• Clean chimneys and flues yearly. Keep them free of debris, leaves, and nests for proper air flow. Also, have a professional check for rust and corrosion, cracks, or separations. These conditions can prevent proper air movement and cause backdrafting. Never “cap” or cover a chimney in any way that would block air flow.
• Test and maintain all fuel-burning equipment annually. Many local gas or oil
companies and HVAC companies offer appliance inspections for a nominal fee.
• Make regular visual inspections of all fuel-burning appliances. Check appliances for excessive rust and scaling. Also check the flame on the burner and pilot lights. The flame should be blue. A yellow flame means fuel is not being burned completely and CO may be present. Keep the blower door on the furnace closed. Use vents or fans when they are available on all fuel-burning appliances. Make sure appliances are vented to the outside. Do not grill or barbecue indoors, or in garages or on screen porches.
• Check for exhaust backflow from CO sources. Check the draft hood on an operating furnace for a backdraft. Look for cracks on furnace heat exchangers.
• Check the house or garage on the other side of shared wall.
• Keep windows and doors open slightly. If you suspect that CO is escaping into your home, open a window or a door. Opening windows and doors can significantly decrease CO levels.
In addition, familiarize yourself with all enclosed materials. Read this manual in its
entirety, and make sure you understand what to do if your Gas/CO Alarm sounds.
UNDERSTANDING THE LIGHT, HORN, AND DISPLAY PATTERNS
Condition LED Horn Display
NORMAL AC POWER LED is Green Silent All segments of display are turned on for a short time upon initial power. Then the battery level icon is displayed.
BATTERY BACK-UP POWER LED is Off, flashing Green once every 45 seconds Silent All segments of display are turned On for a short time upon initial power. Then the battery level icon is displayed flashing.
DURING TESTING LED flashes Red in sync with the horn, simulating an Alarm condition: first gas then CO
First, the horn pattern for gas alarm (1 beep every second) is issued, and then the CO alarm horn pattern (4 beeps, pause, 4 beeps) is issued.
During the simulated gas alarm, “GAS” is displayed along with a full alarm level.
During the simulated CO alarm, “CO” is displayed along with a full alarm level.
Several ppm CO levels are also displayed and the alarm level is shown increasing.
LOW OR MISSING BATTERY Normal A chirp is issued about every minute.Battery icon will show either 1 bar or an empty icon.
GAS ALARM CONDITION LED flashes Red in sync with horn Repeating 1 beep every second “GAS”, a full level, and “EVACUATE”
CARBON MONOXIDE ALARM LED flashes Red in sync with horn Repeating 4 beeps, pause “CO” alternating with the ppm number, a full level, and “EVACUATE”.
PRE-ALARM CONDITION CO IS PRESENT
Normal Normal “CO” alternating with the ppm number. The level will indicate relative CO exposure level.
MALFUNCTION LED flashing Green 3 times in sync with 3 chirps 3 chirps every minute “Err” is displayed.
LOW BATTERY SILENCE LED is Green Silent “bat” and “SILENCE” are displayed.
END OF LIFE LED flashing Green 5 times in sync with 5 chirps 5 chirps every minute “End” is displayed.
WHERE THIS ALARM SHOULD NOT BE INSTALLED
To avoid causing damage to the unit, to provide optimum protection, and to prevent unnecessary alarms, Do NOT locate this Alarm:
• In garages, kitchens, crawl spaces and unfinished attics. Avoid extremely dusty, dirty or greasy areas. Installation in these areas could lead to nuisance alarms, may expose the sensor to substances that could damage or contaminate it, or the Alarm may not be heard by persons in other areas of the home, especially if they are sleeping.
• In the garage, vehicle exhaust can contain some carbon monoxide. These levels are higher when the engine is first started. Within hours of starting a vehicle and backing it out of the garage, the levels present over time can activate the Alarm and become a nuisance.
• In the kitchen, some gas appliances can emit a short burst of CO or gas upon start-up. This is normal. If your Explosive Gas/CO Alarm is installed too close to these appliances, it may alarm often and become a nuisance.
• Keep units at least 20 feet (6 meters) from the sources of combustion particles (stove, furnace, water heater, space heater) if possible. In areas where a 20-foot (6m) distance is not possible – in modular, mobile, or smaller homes, for example – it is recommended the Alarm be placed as far from these fuel-burning sources as possible. The placement recommendations are intended to keep these Alarms at a reasonable distance from a fuel-burning source, and thus reduce “unwanted” alarms. Unwanted alarms can occur if an Alarm is placed directly next to a
fuel-burning source. Ventilate these areas as much as possible. If you must install the Alarm
near a cooking or heating appliance, install at least 5 feet (1.5 meters) from appliance.
• In extremely humid areas. This Alarm should be at least 10 feet (3 meters) from a shower, sauna,
humidifier, vaporizer, dishwasher, laundry room, utility room, or other source of high humidity.
• In direct sunlight.
• In turbulent air, like near ceiling fans or open windows. Blowing air may prevent CO or gas from reaching the sensors.
• In areas where temperature is colder than 40˚ F (4.4˚ C) or hotter than 100˚ F (37.8˚ C). These areas include non-airconditioned crawl spaces, unfinished attics, uninsulated or poorly insulated ceilings, porches, and garages.
• Less than 12 inches (305 mm) away from fluorescent lights. Electrical “noise” can interfere with the sensor.
• In “dead air” spaces. See “Avoiding Dead Air Spaces”.
AVOIDING DEAD AIR SPACES
“Dead air” spaces may prevent gas from reaching the Alarm. To avoid
dead air spaces, follow installation recommendations below.
On ceilings, install Alarms as close to the center of the ceiling as possible. If this is not possible, install the Alarm at least 4 inches (102 mm) from the wall or corner.
For wall mounting, the top edge of Alarms should be placed between 6 inches (152 mm) and 12 inches (305 mm) from the wall/ceiling line.
On a peaked, gabled, or cathedral ceiling, install Alarm within 3 feet
(0.9 meters) of the peak of the ceiling, measured horizontally.
BEFORE YOU BEGIN INSTALLATIONSince CO generally mixes well with air, mounting the Alarm will depend on the type of explosive gas you intend to detect. If you are not certain which type of gas you are using in your home, please read about natural gas and propane in “Where to Install this Alarm”.
• Make sure the alarm is not receiving excessively noisy power. Examples of noisy power could be major appliances on the same circuit, power from a generator or solar power, light dimmer on the same circuit or mounted near fluorescent lighting. Excessively noisy power may cause damage to your Alarm.
Find the pair of self-adhesive labels included with this Gas/CO Alarm.
• On each label write in the phone number of your emergency responder (like 911) and a qualified appliance technician.
• Place one label near the Gas/CO Alarm, and the other label in the “fresh air” location you plan to go if the alarm sounds.
HOW TO INSTALL THIS GAS/CO ALARMIMPORTANT! Read all instructions before using this product.
Tools you will need: Screwdriver, drill.
1. Determine the best location for your Gas/CO Alarm.
2. Your Alarm is equipped to be mounted as a corded unit (recommended for natural gas detection), a direct plug unit (recommended for propane gas detection). The unit can be plugged directly into a wall outlet. If your outlets are mounted horizontally, refer to “If Outlet is Mounted Horizontally (Sideways)” If the adapter is taken out of the unit, the Alarm can be installed high on the wall, while the adapter is plugged into a wall outlet. The explosive gas you use will determine if the Alarm should be installed high on the wall (AC cord option) or low on the wall (direct plug option).
ACTIVATING THE BATTERY BACK-UP

Activate the battery back-up by installing the battery. The battery is for back-up only and is
not intended to power the Alarm for an extended period of time in the absence of AC.
The Alarm will light-up the display briefly to indicate the unit is receiving power.
DIRECT PLUG ALARM INTO AN OUTLET (FOR PROPANE DETECTION)
This Alarm can be plugged directly into a wall outlet located close to the floor. This is the recommended configuration for detecting propane.
1. Choose a standard UNSWITCHED 120V AC outlet.
2. Plug Alarm in.
IF OUTLET IS MOUNTED HORIZONTALLY (SIDEWAYS)`
If you are going to use your Alarm as a direct plug into an outlet that is mounted
horizontally (sideways), you may want to rotate the adapter 90º, as follows:
1. With back of unit facing you (AC blades on your left), place your left thumb on adapter release and grab AC blades with your right hand to release the left side.
2. Repeat for the other side adapter thumb release. This will allow adapter to slide out.
3. Remove adapter.
4. Rotate the adapter 90º and snap firmly back into place.
5. Plug Alarm into AC outlet.
SECURING THE POWER CORD TO AN OUTLET
DISCONNECT POWER TO THE OUTLET TO AVOID ELECTRICAL SHOCK.
1. Remove the wallplate screw from the outlet and hold the wallplate in position.
2. Plug the power cord into the wall outlet so that the screw hole lines up with the wallplate screw hole.
3. Insert the screw through the power cord screw hole and into the wallplate screw hole.
4. Tighten screw in place and restore power to the outlet.
WALL MOUNTED ALARM (FOR NATURAL GAS DETECTION)

Installation tips for power cord models: The power cord option provides more flexibility in
mounting locations and allows the Alarm to be easily installed at or above eye level.
NOTE: If you mount the Alarm high on a wall, make sure it is between 6 to 12 inches
(152-305 mm) down from the ceiling. Any higher than this, it will be in “dead air” space and carbon monoxide or natural gas may not reach the sensors.
NOTE: Do not cover the Alarm with a curtain.
To install for a wall-mount, you will need to pull out the removable adapter and power cord, as follows:
1. 1. Repeat steps 1 to 3 as described above in “to rotate the adapter”.
2. With adapter out, pull out power cord and unwrap it.
3. Insert the screws provided until head is approx. 1/8 inch (3 mm) from wall (if mounting in plaster board or drywall, drill 3/16 inch (5 mm) hole and use plastic anchor provided). Use mounting guide template to locate holes as shown in diagram below.
4. Hook the Alarm over the screw onto the keyhole in back of unit.
5. Plug power cord into AC outlet.
TEST THE ALARM
1. Make sure the Alarm is receiving AC power. Under normal operation, the Green indicator light will shine continuously. If the Green power indicator light does not light, recheck connections. If connections are correct and the Green power indicator still does not light, the unit should be replaced immediately.
2. Press and hold the test button until the alarm sounds. You will hear the signal that indicates the
presence of explosive gas followed by the signal for carbon monoxide.

When testing the Alarm, have someone else check that the Alarm can be heard easily from
the sleeping areas. The unit should be located where it can wake you if it alarms at night.
1. Test/Silence Button: Press and hold to activate test, or to silence the alarm.
2. POWER Light (GREEN)
3. Display
4. (Behind the Cover) Alarm Horn: 85 dB audible alarm for test, alarm, and unit malfunction warning.
5. Display Button: Press to recall highest CO level recorded
6. Battery Compartment
23
4
1
5
6
HOW YOUR ALARM WORKS
THE COVER OF YOUR ALARM
REGULAR MAINTENANCE
This unit has been designed to be as maintenance-free as possible, but there
are a few simple things you must do to keep it working properly:
• Test it at least once a week.
• Clean the Alarm at least once a month; gently vacuum the outside of the Alarm using your household vacuum’s soft brush attachment. Test the Alarm. Never use water, cleaners or solvents since they may damage the unit.
• Relocate the unit if it sounds frequent unwanted alarms. See “Where This Alarm Should Not Be Installed” for details.
• When the battery back-up becomes weak, the Alarm will “chirp” about once a minute (the low battery warning). You should replace the battery immediately to continue your protection.
This Alarm must have AC or battery power to operate. If AC power fails, and the battery is dead or missing, the Alarm cannot operate.
DO NOT spray cleaning chemicals or insect sprays directly on or near the Alarm. DO NOT paint over the Alarm. Doing so may permanently damage the Alarm.
CHOOSING A REPLACEMENT BATTERY:
Your Alarm requires one standard 9V alkaline battery. The following batteries
are acceptable as replacements: Duracell #MN1604, (Ultra) #MX1604; Eveready
(Energizer) #522. These batteries are available at many local retail stores.
• Always use the exact batteries specified by this User’s Manual. DO NOT use rechargeable batteries. Clean the battery contacts and also those of the device prior to battery installation. Install batteries correctly with regard to polarity (+ and -).
• Please dispose of or recycle used batteries properly, following any local regulations. Consult your local waste management authority or recycling organization to find an electronics recycling facility in your area. DO NOT DISPOSE OF BATTERIES IN FIRE. BATTERIES MAY EXPLODE OR LEAK.
• Keep battery out of reach of children. In the event a battery is swallowed,
immediately contact your poison control center, your physician, or the National
Battery Ingestion hotline at 202-625-3333 as serious injury may occur.
Actual battery service life depends on the Alarm and the environment in which it is installed. All the batteries specified above are acceptable replacement batteries for this unit. Regardless of the manufacturer’s suggested battery life, you MUST replace the battery immediately once the unit starts “chirping” (the “low battery warning”).
WHAT YOU NEED TO KNOW ABOUT CO
WHAT IS CO?CO is an invisible, odorless, tasteless gas produced when fossil fuels do not burn completely, or are exposed to heat (usually fire). Electrical appliances typically do not produce CO.
These fuels include: Wood, coal, charcoal, oil, natural gas, gasoline, kerosene, and propane.
Common appliances are often sources of CO. If they are not properly maintained, are improperly ventilated, or malfunction, CO levels can rise quickly. CO is a real danger now that homes are more energy efficient. “Air-tight” homes with added insulation, sealed windows, and other weatherproofing can “trap” CO inside.
SYMPTOMS OF CO POISONINGThese symptoms are related to CO POISONING and should be discussed with ALL household members.
Mild Exposure: Slight headache, nausea, vomiting, fatigue (“flu-like” symptoms).
Medium Exposure: Throbbing headache, drowsiness, confusion, fast heart rate.
Extreme Exposure: Convulsions, unconsciousness, heart and lung failure. Exposure to Carbon Monoxide can cause brain damage, death.

Some individuals are more sensitive to CO than others, including people with cardiac or
respiratory problems, infants, unborn babies, pregnant mothers, or elderly people can be
more quickly and severely affected by CO. Members of sensitive populations should consult
their doctors for advice on taking additional precautions.

FINDING THE SOURCE OF CO AFTER AN ALARMCarbon monoxide is an odorless, invisible gas, which often makes it difficult to locate the source of CO after an alarm. These are a few of the factors that can make it difficult to locate sources of CO:
• House well ventilated before the investigator arrives.
• Problem caused by “backdrafting.”
• Transient CO problem caused by special circumstances.
Because CO may dissipate by the time an investigator arrives, it may be difficult to locate the source of CO. BRK Brands, Inc. shall not be obligated to pay for any carbon monoxide investigation or service call.
REGULATORY INFORMATION FOR EXPLOSIVE GAS/CO ALARMS
REGULATORY INFORMATION FOR CO ALARMS
UNDERWRITERS LABORATORIES INC. UL2034
WHAT LEVELS OF CO CAUSE AN ALARM?
Underwriters Laboratories Inc. Standard UL2034 requires residential CO Alarms to sound when exposed to levels of CO and exposure times as described below. They are measured in parts per million (ppm) of CO over time (in minutes).
UL2034 Required Alarm Points*:
• If the alarm is exposed to 400 ppm of CO, IT MUST ALARM BETWEEN 4 and 15 MINUTES.
• If the alarm is exposed to 150 ppm of CO, IT MUST ALARM BETWEEN 10 and 50 MINUTES.
• If the alarm is exposed to 70 ppm if CO, IT MUST ALARM BETWEEN 60 and 240 MINUTES.
Approximately 10% COHb exposure at levels of 10% to 95% Relative Humidity (RH).
The unit is designed not to alarm when exposed to a constant level of 30 ppm for 30 days.
CO Alarms are designed to alarm before there is an immediate life threat. Since you cannot see or smell CO, never assume it’s not present.• An exposure to 100 ppm of CO for 20 minutes may not affect average, healthy adults, but after 4 hours the same level may cause headaches.
• An exposure to 400 ppm of CO may cause headaches in average, healthy adults after 35 minutes, but can cause death after 2 hours.
This CO Alarm measures exposure to CO over time. It alarms if CO levels are extremely high in a short period of time, or if CO levels reach a certain minimum over a long period of time. The CO Alarm generally sounds an alarm before the onset of symptoms in average, healthy adults.Why is this important? Because you need to be warned of a potential CO problem while you can still react in time. In many reported cases of CO exposure, victims may be aware that they are not feeling well, but become disoriented and can no longer react well enough to exit the building or get help. Also, young children and pets may be the first affected. The average healthy adult might not feel any symptoms when the CO Alarm sounds. However, people with cardiac or respiratory problems, infants, unborn babies, pregnant mothers, or elderly people can be more quickly and severely affected by CO. If you experience even mild symptoms of CO poisoning, consult your doctor immediately!
Standards: Underwriters Laboratories Inc. Single and Multiple
Station carbon monoxide alarms UL2034.
According to Underwriters Laboratories Inc. UL2034, Section 1-1.2: “Carbon monoxide alarms covered by these requirements are intended to respond to the presence of carbon monoxide from sources such as, but not limited to, exhaust from internal-combustion engines, abnormal operation of fuel-fired appliances, and fireplaces. CO Alarms are intended to alarm at carbon monoxide levels below those that could cause a loss of ability to react to the dangers of Carbon Monoxide exposure.” This CO Alarm monitors the air at the Alarm, and is designed to alarm before CO levels become life threatening. This allows you precious time to leave the house and correct the problem. This is only possible if Alarms are located, installed, and maintained as described in this manual.
Gas Detection at Typical Temperature and Humidity Ranges: The CO Alarm is not formulated
to detect CO levels below 30 ppm typically. UL tested for false alarm resistance to Methane (500
ppm), Butane (300 ppm), Heptane (500 ppm), Ethyl Acetate (200 ppm), Isopropyl Alcohol (200 ppm)
and Carbon Dioxide (5000 ppm). Values measure gas and vapor concentrations in parts per million.
Audible Alarm: 85 dB minimum at 10 feet (3 meters).
REGULATORY INFORMATION FOR EXPLOSIVE GAS ALARMS
Standards: Underwriters Laboratories Inc. UL1484.
According to Underwriters Laboratories Inc. UL1484, this unit meets the alarm response time for gas as follows: This unit shall alarm before 25% of the LEL of either natural gas or propane is detected. In all cases, the unit will detect gas as a priority over carbon monoxide. If the device is detecting CO, then detects an amount of gas to cause an alarm, the device will stop alarming for CO and begin to alarm for gas.
GENERAL LIMITATIONS OF EXPLOSIVE GAS/CO ALARMS
This Gas/CO Alarm is intended for residential use. It is not intended for use in industrial applications
where Occupational Safety and Health Administration (OSHA) requirements for Carbon Monoxide
Alarms must be met. This device is not intended to alert hearing impaired residents.
Gas/CO Alarms may not waken all individuals. If children or others do not readily waken to the sound of the Gas/CO Alarm, or if there are infants or family members with mobility
limitations, make sure that someone is assigned to assist them in the event of an emergency.
This Gas/CO Alarm will not sense gas or CO that does not reach the sensors. It will
only sense gas or CO at the sensor. Gas or CO may be present in other areas. Doors or
other obstructions may affect the rate at which CO or gas reaches the sensors.
Gas/CO Alarms may not be heard. The alarm horn loudness meets or exceeds current UL standards of 85 dB at 10 feet (3 meters). However, if the Gas/CO Alarm is installed outside the bedroom, it may not wake up a sound sleeper or one who has recently used drugs or has been drinking alcoholic beverages. This is especially true if the door is closed or only partly open. Even persons who are awake may not hear the alarm horn if the sound is blocked by distance or closed doors. Noise from traffic, stereo, radio, television, air conditioner, or other appliances may also prevent alert persons from hearing the alarm horn. This Gas/CO Alarm is not intended for people who are hearing impaired.
This Gas/CO Alarm is not a substitute for life insurance. Though this Gas/CO Alarm warns against increasing CO levels or the presence of gas, BRK Brands, Inc. does not warrant or imply in any way that they will protect lives. Homeowners and renters must still insure their lives.
This Gas/CO Alarm is not foolproof. Like all other electronic devices, this Gas/CO Alarm has
limitations. It can only detect gas or CO that reaches the sensors. It may not give early warning
of the source of gas or CO is in a remote part of the home, away from the alarm device.
This Gas/CO Alarm has a limited life. Although this Gas/CO Alarm and all of its parts have passed many stringent tests and are designed to be as reliable as possible, any of these parts could fail at any time. Therefore, you must test this device weekly. The unit should be replaced immediately if it is not operating properly.
LIMITED WARRANTY
BRK Brands, Inc., (“BRK”) the maker of First Alert® brand and BRK® brand products, warrants that for a period of ten years from the date of purchase, this product will be free from defects in material and workmanship. BRK, at its option, will repair or replace this product or any component of the product found to be defective during the warranty period. Replacement will be made with a new or remanufactured product or component. If the product is no longer available, replacement may be made with a similar product of equal or greater value. This is your exclusive warranty.
This warranty is valid for the original retail purchaser from the date of initial retail purchase and is not transferable. Keep the original sales receipt. Proof of purchase is required to obtain warranty performance. BRK dealers, service centers, or retail stores selling BRK products do not have the right to alter, modify or any way change the terms and conditions of this warranty.
This warranty does not cover normal wear of parts or damage resulting from any of the following: negligent use or misuse of the product, use on improper voltage or current, use contrary to the operating instructions, disassembly, repair or alteration by anyone other than BRK or an authorized service center. Further, the warranty does not cover Acts of God, such as fire, flood, hurricanes and tornadoes or any batteries that are included with this unit.
BRK shall not be liable for any incidental or consequential damages caused by the breach of any express or implied warranty. Except to the extent prohibited by applicable law, any implied warranty of merchantability or fitness for a particular purpose is limited in duration to the duration of the above warranty. Some states, provinces or jurisdictions do not allow the exclusion or limitation of incidental or consequential damages or limitations on how long an implied warranty lasts, so the above limitations or exclusion may not apply to you. This warranty gives you specific legal rights, and you may also have other rights that vary from state to state or province to province.
How to Obtain Warranty Service
Service: If service is required, do not return the product to your retailer. In order to obtain warranty service, contact the Consumer Affairs Division at 1-800-323-9005. To assist us in serving you, please have the model number and date of purchase available when calling.
For Warranty Service return to: BRK Brands, Inc., 1301 Joe Battle, El Paso, TX 79936
Battery: BRK Brands, Inc. make no warranty, express or implied, written or oral, including that of merchantability or fitness for any particular purpose with respect to battery.
Visit www.firstalert.com for more information.
For your records, please record:
Date Purchased: _______________________________
Where Purchased: ____________________________________________
Date Installed: ____________/____________Month/Year
Replace alarm 5 years after installation. Please write the date in the space provided:
_____________/____________Month/Year
The alarm will also provide an audible End-of-Life Signal approximately 5 years after installation to remind you to replace the unit.
The End-of-Life Signal can be silenced for up to 2 days. Do not unplug
the alarm or remove the batteries until you get replacement.
vv TROUBLESHOOTING GUIDE
If your Alarm does this..., It means...It means...You should...
Green light is OFF. Unit will not alarm when you press the Test/Silence button.Unit may not be receiving any power.Check the AC power supply. Make sure a fresh 9V
battery is installed to power the battery back-up.
Green light flashes ON, once a minute (horn is silent).Alarm is not receiving AC power. Unit is operating on battery back-up.Check the AC power supply.
The horn “chirps” once a minute.Low battery warning. Battery is low or missing.Replace the battery. Avoid interrupting AC power.
v Once a minute, the alarm sounds 3 “chirps”, and the green light flashes three times.MALFUNCTION SIGNAL. Based on its Self Test diagnostics, the unit has detected a malfunction. The unit needs to be replaced.Units under warranty should be returned to manufacturer for replacement. See “Limited Warranty” for details.
The light flashes (Green) and the horn sounds 5 “chirps” every minute.END OF LIFE SIGNAL. Alarm needs to be replaced Immediately replace the Alarm.
The horn sounds constantly with no pattern and cannot be silenced,Unit malfunction. Unit needs to be replaced.Units under warranty should be returned to manufacturer for replacement. See “Limited Warranty” for details.
Alarm goes back into alarm after you pressed the Test/Silence button to silence an alarm.Gas and/or CO levels are still potentially dangerous.Refer to “If Your Gas/CO Alarm Sounds” for details on how to respond to an alarm. If anyone is feeling ill, EVACUATE your home immediately and call 911.
Alarm sounds frequently even though no high levels of gas or CO are revealed in an investigation.Alarm sounds frequently even though no high levels of gas or CO are revealed in an investigation.Relocate your alarm. If frequent alarms continue, have home rechecked for potential problems. You may be experiencing an intermittent gas or CO problem.
*For a list of acceptable replacement batteries, see “Regular Maintenance.”
If you have any questions that cannot be answered by reading this manual, call Consumer Affairs: 1-800-323-9005.
Appendix D
Landfill Gas Meter Calibration Logs
CALIBRATION LOG
LANDTEC - GEM 5000+
ES # 1255
Instrument: LANDTEC Serial Number: G502512
Calibrated materials required:
Lot:304-402130279-1 Lot:304-402229328-1
Exp:6/7/2025 Exp:10/7/2025
Lot:304-402229330-1 Lot:304-402342277-1
Exp:10/7/2025 Exp:2/2/2026
Lot:304-402229329-1 Lot:304-402229326-1
Exp:10/7/2025 Exp:10/7/2023
.
Carbon Filter Saturation (CH4) - Condition: PASS
Gas Calibration Check Performed at Room Temperature
GEM 5000+ (FRESH AIR CALIBRATION)
SENSOR Initial Reading CAL Reading Tolerance Comments
CH4 (%)0.0 0.0 +/- 0.5%
CO (ppm)0.0 0.0 +/- 5 ppm
H2S (ppm)0.0 0.0 +/- 5 ppm
H2 (%)0.0 0.0 +/- 1.5%
METHANE HIGH CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance CommentsCH4 (%)46.5 50.0 +/- 0.5%C02 (%)32.5 35.0 +/- 1.5%O2 (%)-0.3 0.0 +/- 1.5%
METHANE LOW CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance CommentsCH4 (%)10.4 10.0 +/- 0.5%C02 (%)10.3 10.0 +/- 1.5%
O2 (%)0.0 0.0 +/- 1.5%
OXYGEN HIGH CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance Comments
O2 (%)20.9 20.9 +/- 0.5%
OXYGEN LOW CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance Comments
O2 (%)3.9 4.0 +/- 0.5%
CARBON MONOXIDE CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance Comments
CO (ppm)1011 1000 +/- 50 ppm
HYDROGEN SULFIDE CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance Comments
H2S (ppm)180 200 +/- 10 ppm
Signature: fz Date: 07/08/2022
METHANE HIGH OXYGEN LOW
METHANE LOW CARBON MONOXIDE
OXYGEN HIGH HYDROGEN SULFIDE
CALIBRATION LOG
LANDTEC - GEM 5000+
ES # 1255
Instrument: LANDTEC Serial Number: G502512
Calibrated materials required:
Lot:304-402130279-1 Lot:304-402229328-1
Exp:6/7/2025 Exp:10/7/2025
Lot:304-402229330-1 Lot:304-402342277-1
Exp:10/7/2025 Exp:2/2/2026
Lot:304-402229329-1 Lot:304-402229326-1
Exp:10/7/2025 Exp:10/7/2023
.
Carbon Filter Saturation (CH4) - Condition: PASS
Gas Calibration Check Performed at Room Temperature
GEM 5000+ (FRESH AIR CALIBRATION)
SENSOR Initial Reading CAL Reading Tolerance Comments
CH4 (%)0.0 0.0 +/- 0.5%
CO (ppm)0.0 0.0 +/- 5 ppm
H2S (ppm)0.0 0.0 +/- 5 ppm
H2 (%)-10.0 0.0 +/- 1.5%
METHANE HIGH CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance CommentsCH4 (%)49.9 50.0 +/- 0.5%C02 (%)35.0 35.0 +/- 1.5%O2 (%)0.0 0.0 +/- 1.5%
METHANE LOW CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance CommentsCH4 (%)10.6 10.0 +/- 0.5%C02 (%)10.4 10.0 +/- 1.5%
O2 (%)-0.1 0.0 +/- 1.5%
OXYGEN HIGH CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance Comments
O2 (%)21.5 20.9 +/- 0.5%
OXYGEN LOW CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance Comments
O2 (%)4.4 4.0 +/- 0.5%
CARBON MONOXIDE CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance Comments
CO (ppm)1001 1000 +/- 50 ppm
HYDROGEN SULFIDE CALIBRATION
SENSOR Initial Reading CAL Reading Tolerance Comments
H2S (ppm)206 200 +/- 10 ppm
Signature: RQA Date: 08/04/2022
METHANE HIGH OXYGEN LOW
METHANE LOW CARBON MONOXIDE
OXYGEN HIGH HYDROGEN SULFIDE