10002_Rea_ Building 5-VMI Letter 2012_12_21

Certification of Vapor Mitigation Installation-Building 5 S&ME Project Number 1353-12-060
Silos, Charlotte, NC (Brownfields Site No. 11009-07-60) December 21, 2012
______________________________________________________________________________________
2
Vapor Mitigation System
As approved in the Notification letter, the vapor mitigation system for Building 5
consisted of an active venting system as well as a spray-applied (Geo-Seal®) seamless
membrane located beneath the building’s concrete slab and above the ground surface.
The active venting system consists of a Geo-Seal Vapor Vent piping system incorporated
within the gravel subgrade that is piped from below the building slab, through the
building walls to centrifugal fans (blowers) located on the roof. The membrane consists
of a bottom layer of Geo-Seal Base, then the spray-applied 60-mil (minimum thickness)
Geo-Seal Core, and topped with a Geo-Seal Bond layer. The installation of the vapor
mitigation system was generally installed per the design specified in the approved April
12, 2012 Notification letter and appended Technical Specifications for Vapor Barrier And
Active Venting System, Silos Community (Technical Specifications) dated April 11, 2012
prepared by WSP-Sells. The only deviation from these specifications was the August 24,
2012, NCDENR-approved reduction in specified curing time of the spray-applied barrier
(Geo-Seal Core) prior to collecting thickness measurements. This reduced curing time
was based on information and specifications provided to the NCDENR by the
manufacturer.
Installation Dates
The installation of the vapor vent and barrier systems below Building 5 was done in
multiple stages due to construction logistical scheduling, weather delays, etc. Installation
activities began on August 24, 2012 at the Building 5 elevator pit only. Installation of the
Vapor Vent piping began on October 26, 2012 and was completed on October 27, 2012
for the rest of the building. Application of the overlying vapor barrier began in October
27 and was completed on December 11, 2012. S&ME was present and observed the
installation and conducted the specified Quality Assurance/Quality Control (QA/QC)
testing on the dates listed on Table 1.Figure 4 indicates the approximate location of the
various QA/QC thickness test locations.
QA/QC Testing
As specified in the approved Notification and Technical Specifications, S&ME conducted
and/or observed the following QA/QC testing during membrane installation:
Observed the ground surface for sharp objects prior to installing the barrier
system;
Observed and documented the installation of the Geo-Seal Vapor Vent system;
Observed and documented the installation of the Geo-Seal Base;
Observed and documented the installation of the spray-applied Geo-Seal Core;
Observed the sealing of penetrations (i.e., piping, wiring conduits, etc.);
Collected two samples per approximate 1,000 square feet of the Geo-Seal Base
and Geo-Seal Core after application and measured for thickness;
FIGURES
Scale: AS SHOWN
Checked by:DAH
Drawn by: RAS
Date:11/1/12
USGS Topographic Map
Silos Site
121 Lancaster Street
Charlotte, North Carolina
Figure
1S&ME Project No.: 1353-12-060
Site Area
Charlotte West USGS Quadrangle dated 1993 and Charlotte East USGS Quadrangle dated 1967 and Photorevised in 1988.
Scale: AS SHOWN
Checked by: DAH
Drawn by: RAS
Date:11/1/12
2009 Aerial Photographic Map
Silos Site
121 Lancaster Street
Charlotte, North Carolina
Figure
2S&ME Project No.: 1353-12-060
Base Map obtained from Mecklenburg County GIS Website
Site Boundary
Light Rail
Corridor
South
Boulevard
Youngblood
Street
Fairwood
Avenue
Griffith
Street
Lancaster
Street
Remount
Road
Approximate
Scale: 1” = 186’
Silos
SILOS (EXISTING)SILOS (EXISTING)SILOS (EXISTING)
POOL AREA
S I T E C O N C E P T U A L P L A N
P R O P O S E D W O O D F I E L D S I L O S C O M M U N I T Y
L A N C A S T E R S T R E E T & Y O U N G B L O O D S T R E E T
C H A R L O T T E , N O R T H C A R O L I N A
3
1 3 5 4 -1 1 -1 9 8
1 " = 8 0
D D H
1 -1 1 -2 0 1 2
R A S
FIGURE NO.
S C A L E :
P R O J E C T N O :
D A T E :
D R A W N B Y :
C H E C K E D B Y :
W W W .S M E I N C .C O M
REFERENCE:BASE MAP PROVIDED BY DESIGN RESOURCE GROUP, PA. PLEASE NOTE THIS MAP IS FOR INFORMATIONAL PURPOSES ONLY. IT IS NOTMEANT FOR DESIGN, LEGAL, OR ANY OTHER USES. THERE ARE NO GUARANTEES ABOUT ITS ACCURACY. S&ME, INC. ASSUMES NORESPONSIBILITY FOR ANY DECISION MADE OR ANY ACTIONS TAKEN BY THE USER BASED UPON THIS INFORMATION.
0 80 160
Feet ±
h h
h h
1
2
3
4
4A
5
5A
6
6A
7
8
9 10
11
12
12A
131414A
15
15A 16
17
18
18A
R1 R2
12
B U I L D I N G 5 V A P O R B A R R I E R
T H I C K N E S S S A M P L E L O C A T I O N S
W O O D F I E L D S I L O S C O M M U N I T Y
L A N C A S T E R S T R E E T & Y O U N G B L O O D S T R E E T
C H A R L O T T E , N O R T H C A R O L I N A
4
1 3 5 3 -1 2 -0 6 0
D D H
1 2 .1 9 .2 0 1 2
D A H
FIGURE NO.
S C A L E :
P R O J E C T N O .
D A T E :
D R A W N B Y :
C H E C K E D B Y :
W W W .S M E I N C .C O M
REFERENCE:BASE DRAWING PROVIDED BY WSP SELLS. PLEASE NOTE THIS MAP IS FOR INFORMATIONALPURPOSES ONLY. IT IS NOT MEANT FOR DESIGN, LEGAL, OR ANY OTHER USES. THERE ARE NOGUARANTEES ABOUT ITS ACCURACY. S&ME, INC. ASSUMES NO RESPONSIBILITY FOR ANYDECISION MADE OR ANY ACTIONS TAKEN BY THE USER BASED UPON THIS INFORMATION.
0 20 40
Feet
±
1 " = 2 0 '
F -0 1 7 6
E N G I N E E R I N G L I C E N S E N O .
Q :\1 3 5 3 \2 0 1 2 \0 6 0 S i l o s \f i g 4 _V a p o r B a r r i e r S a m p l e s B l d g 5 .m x d
h Approximate Exhaust Line
Approximate Vapor Vent Piping
Approximate Sample Locations
Vapor Barrier Installation Dates:
8/24/2012
11/2/2012
12/11/2012
TABLE
Table 1
Summary of QA/QC Testing Results
Observe
Installation?
Generally
Installed per
Specifications?
Sample
ID
Average
Thickness1
Pass/
Fail2
1 0.1420 Pass
2 0.1193 Pass
10/27/2012 Observe installation of Vapor Vent
System within gravel
Building 5-
Remainder of
Building
Yes Yes No N/A N/A N/A No N/A
1 0.1158 Pass
2 0.1105 Pass
3 0.0963 Pass
4 0.0681 Fail
5 0.0625 Fail
6 0.0640 Fail
7 0.0886 Pass
8 0.0791 Pass
9 0.0958 Pass
10 0.0646 Fail Not retested, but passed smoke test
11 0.0826 Pass
12 0.0646 Fail
13 0.0951 Pass
14 0.0616 Fail
15 0.0535 Fail
16 0.0910 Pass
17 0.1020 Pass
18 0.0550 Fail
4A 0.0940 Pass Retest of sample #4 after reapplication
5A 0.0876 Pass Retest of sample #5 after reapplication
6A 0.0800 Pass Retest of sample #6 after reapplication
12A 0.1068 Pass Retest of sample #12 after reapplication
14A 0.1233 Pass Retest of sample #14 after reapplication
15A 0.0975 Pass Retest of sample #15 after reapplication
18A 0.8383 Pass Retest of sample #18 after reapplication
R1 0.0977 Pass
R2 0.1401 Pass
Notes:
N/A = Not Applicable
Vapor Vent Installation
Yes
N/A
NCDENR Brownfields Project No. 11009-07-60
2 Thickness measurement required to be a minimum of 74 mil (0.074") for 14 mil thickGeo-Seal Base layer and 60 mil thickGeo-Seal Core layer in order to meet specification requirement of 60 mil forGeo-Seal Core layer.
Yes after
additional
application
in some
areas
10/26/2012 Observe installation of Vapor Vent
System within gravel
Building 5,
South side
Building No. 5 - Silos Community
Poindexter Drive & Griffith Street
Charlotte, Mecklenburg County, North Carolina
S&ME Project No. 1353-12-060
Date Activity Location
Thickness
Measured?
Thickness Measurements Smoke
Testing
Conducted?
Smoke
Testing
Pass?
Comment
11/1 & 2/2012
Observe Vapor Vent system after
installation; observe installation of Base,
spray-applied Core layer; collect
thickness samples, and observe smoke
testing.
Building 5 Yes YesNo
Yes
1 Thickness measured with pre-calibrated calipers.
3 On August 17, 2012, NCDENR verbally approved a reduction in required curing time that reduced the time between application of spray-on barrier (Core layer) and thickness testing from >24 hrs to same day as application. An email
written approval was sent from the NCDENR on August 24, 2012.
No N/A N/A N/A No N/A
Yes Yes
As indicated above, Sample 10 collected and measured on Nov. 2, 2012 failed the thickness measurement at an average thickness of 0.0646 mil and the area was resprayed but follow up thickness samples were not collected. However,
the area passed smoke testing.
12/11/2012
Observe installation of Base, spray-
applied Core layer, collect thickness
samples and smoke test. (Vapor vent
system installation of this area observed
on 11/2/12)
Building 5
Ramp Yes Yes Yes
Yes Yes8/24/2012
Observe installation of Base, spray-
applied Core, collected thickness
samples, and smoke tested.
Building 5,
Elevator Pit
No N/A Yes
SITE PHOTOGRAPHS
Silos Community Site
121 Lancaster Street, Charlotte, NC
Project #: 1353-12-060
Sheet 1 of 5
9751 Southern Pine Blvd.
Charlotte, NC 28273
Photo 1
D a t e :
0 8 /2 4 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks Subsurface below elevator pit prior to vapor barrier installation.
Photo 2
D a t e :
0 8 /2 4 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks Installing Geo-Seal Base upon subsurface and piles in elevator pit.
Pile
PilePiles
PilePilesPilePilesPiles
Silos Community Site
121 Lancaster Street, Charlotte, NC
Project #: 1353-12-060
Sheet 2 of 5
9751 Southern Pine Blvd.
Charlotte, NC 28273
Photo 3
D a t e :
0 8 /2 4 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks Patching above piles and spray-applying Geo-Seal Core barrier (black color)
above Geo-Seal Base (gray color) in elevator pit.
Photo 4
D a t e :
1 0 /2 6 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks Building 5 during installation of Geo-Seal Vapor Vent piping within stone.
Silos Community Site
121 Lancaster Street, Charlotte, NC
Project #: 1353-12-060
Sheet 3 of 5
9751 Southern Pine Blvd.
Charlotte, NC 28273
Photo 5
D a t e :
1 0 /2 4 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks Unrolling and installing Geo-Seal Vapor Vent within stone.
Photo 6
D a t e :
1 0 /1 5 /2 0 1 2
P h o t o g r a p h e r .
J i m m y
G o s n e l l
Location Silos Community – Building No. 5
Remarks Geo-Seal Vapor Vent piping being installed in stone.
Vapor
Vent
Silos Community Site
121 Lancaster Street, Charlotte, NC
Project #: 1353-12-060
Sheet 4 of 5
9751 Southern Pine Blvd.
Charlotte, NC 28273
Photo 7
D a t e :
1 0 /2 6 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks Installing Geo-Seal Vapor Vent prior to covering with stone.
Photo 8
D a t e :
1 0 /2 7 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks Piping connection between different sections of Geo-Seal Vapor Vent prior to
covering.
Silos Community Site
121 Lancaster Street, Charlotte, NC
Project #: 1353-12-060
Sheet 5 of 5
9751 Southern Pine Blvd.
Charlotte, NC 28273
Photo 9
D a t e :
1 1 /0 1 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks After installation of Geo-Seal Base and spray-applied Core above stone
containing Vapor Vent, prior to covering with Geo-Seal Bond.
Photo 10
D a t e :
1 1 /0 1 /2 0 1 2
P h o t o g r a p h e r .
B r i a n
W i l s o n
Location Silos Community – Building No. 5
Remarks Building 5 pad after installation of Geo-Seal Vapor Vent piping, Base, thickness
measurements, smoke testing but before covering with Geo-Seal Bond.
Vapor
Vent