No. KT-88-007(R)
EVALUATION OF U-TUBE
UNDERGROUND TANK SYSTEMS
FOR SOIL VAPOR TESTING
Suffolk County, New York
Revised March 1988
-------
-------
,V..:Rep6rt No. KT-88-007(R)
REPORT
EVALUATION OF U-TUBE
UNDERGROUND TANK MONITORING SYSTEMS
FOR SOIL VAPOR TESTING
Suffolk County, New York
Revised March 1988
Submitted to:
Midwest Research Institute
5201 Leesburg Pike
Suite 209
Falls Church, Virginia
22041
By:
Kaman Tempo
816 State Street
Santa Barbara, California
93101
(805)963-6479
-------
-------
Section
TABLE OF CONTENTS
1 INTRODUCTION
4 CONCLUSIONS AND RECOMMENDATIONS
APPENDICES
2 INVESTIGATIVE METHODS ......... . ................... 2'1
2.1 Description of Sites ......................... 2-1
2.2 Testing Methods .................. ...... • ..... z'3
3 RESULTS ...... ". ........................... • ........ 3"1
3.1 Discussion of Total Concentration .......... .. 3-1
3.2 Variation in Chemical Composition ............ 3-6
4.1 Background Concentration ...................... 4-1
4.2 Methodology .................................. 4"2
4.3 Construction Design and
Installation Quality ......................... 4-<*
A Calculation of Relative Detector Sensitivities
for Isobutylene, Benzene, Toluene and Xylene ....... A-l
B Calculations of Concentrations from Photovac
10S30 Peak Areas ................................... B~1
-------
-------
','".. ' LIST Of, FIGURES , :...;;.:| -..:•: ":':'::
Figure ""'"* ^ : £^i
1-1 Schematic Diagram of U-Tube Monitoring System
for Underground Storage Tanks 1-2
1-2 Location Map of Underground Storage Tank Sites . ... 1-4
3-1 Pumping Time Versus Concentration Plots for
Known or Suspected Leak Sites 3'3
3-2 Pumping Time Versus Concentration Plots for Non-Leak
Non-Leak Sites with Moderate Soil-Gas
3-3
3-4
3-5
3-6
•3 7
o— /
3-8
3-9
Pumping Time Versus Concentration Plots for Non-Leak
Qi+nc un-nh i nw 9ni1-fia^ Rarkaround Concentrations
Scattergrams Comparing Performance of Photovac
Depth to Groundwater and Soil-Gas Concentration
Site Age Versus Soil -Gas Background Concentration
Variation in Soil-Gas Chroma tog raphic Signatures
Variation in Soil-Gas Chromatographic Signatures
at Non-Leak Si tes ,
3-4
3-5
3-7
3-8
3-9
3-10
3-12
3-13
-------
-------
'/.;;.- ,. : \ LIST OH TABLES : ...^:* =.-••-• : • :;
Table Page
2-1 Summary of Site Characteristics 2-2
2-2 U-Tube Characteristics and Test Parameters 2-4
3-1 Summary of Background Concentration in U-Tubes 3-2
4-1 Isolated Sites Show the Lowest Background
Concentrations 4-3
-------
-------
SECTION 1
INTRODUCTION
This report is a summary and evaluation of the methodology and results of
background soil vapor concentrations measured in underground storage tank
(LIST) U-tube vapor monitoring devices. Kaman Tempo performed this study under
subcontract to Midwest Research Institute as a contribution to the EPA UST
Federal Guidelines and Regulations.
The study was conducted in'Suffolk County, New York, where a large number
of UST sites with U-tubes have been installed under tight County regulatory
control. The County regulation most relevant to this study is the tank
registration program which provides an identification number, historical use
data, and construction records for each tank.
U-tubes, originally intended for leak detection by liquid interception
rather than vapor monitoring, have been installed beneath hundreds of UST's
since 1980. A schematic U-tube construction diagram is presented in Figure
1-1. The U-tubes consist of an inclined PVC pipe with perforations only in
the upper half placed lengthwise beneath the tank. The up-slope end of the
perforated pipe is connected by a 90° elbow to a vertical riser pipe. The
lower end is connected by a tee to a sump and riser pipe. All parts are
generally of Schedule 40 4-inch PVC. Risers are generally 10 feet long and
inclined sections average 25 feet in length.
The dual purpose of the study was to develop a method for soil background
measurements using U-tubes and to collect a background concentration database
for the study area. In developing the testing method, the usefulness, style
and quality of U-tube installations were also evaluated. The motivating
objective for the soil vapor concentration background database is the regu-
latory need to assign a threshold concentration alarm level for automatic
vapor monitoring systems and periodic manual monitoring programs.
1-1
-------
Sump Riser Elbow Riser
f«al»
-------
••''••'•••' All the sites were selected direttly from the tanfc•Registry with the aid
of additional information provided by Cdunty Health Department •'official s.
Several site criteria were considered in the selection process. For logistic
reasons all sites were selected within a five mile radius. An attempt was
made to select sites with a variety of tank products, tank construction
materials, site leak histories, depth-to-groundwater, and site ages. The
selected locations are presented in Figure 1-2.
Kaman Tempo would like to thank Mr. James Pirn and staff of Suffolk County
Department of Health Services, Bureau of Hazardous Materials, for their
cooperation and assistance in conducting this study.
1-3
-------
Sunken Meadow Pkwy
Northern State Pkwy
Approximate Seal* In Mllaa
#8265
EXPLANATION
Location of underground Storage Tank Site
Showing Identification Number
Figure 1-2. Location Map of Underground Storage Tank Sites.
1-4
-------
SECTION 2
ilWESTIGATIVEf* METHODS
2.1 DESCRIPTION OF SITES
Twenty U-tubes at nine sites were visited during the week of July 20,
1987. The characteristics of each site and tank are summarized in Table 2-1.
Each U-tube and corresponding underground tank is identified in the table by a
Suffolk County tank tax identification number followed by a number designating
the chronological order of testing at a particular site. The three sites
having a suspected or known history of leaks (5036, 8020 and 8037) according
to Suffolk County officials are designated by bold face identification
numbers.
All the tanks tested contained petroleum fuel products including gaso-
line, diesel, and kerosene as well as heating, lubrication, and waste oil.
Diesel was the only product believed to have leaked from visited on-site
tanks; however, measurements were made at Site 8043 of trichloroethylene (TCE)
from a groundwater contamination plume having an off-site source according to
Suffolk County officials. Groundwater concentrations of TCE in the area are
reportedly on the order of several thousand micrograms per liter (ppb).
Groundwater depths ranged from 27 to 161 feet below ground surface and
are bimodally distributed between levels shallower and deeper than 50 feet.
Based upon the number of years that underground storage tanks have been
present, the sites ranged from 7 to 75 years in age. Because the first
U-tubes were installed in Suffolk County in 1980, the tanks tested were no
more than 7 years of age. Tank types were either fiberglass or STIP-3 cathod-
ically protected. No plain steel or buff-hide tanks were available for
testing. Two of the sites were greater than 600 feet distant from any other
underground storage tank, contained only one tank, and therefore are desig-
nated as "isolated" sites.
2-1
-------
Table 2-1. Summary of Site Characteristics.
u-
Tube#
M\
' II
1079
5036-1*
5036-2*
8020-1*
8020-2*
8020-3*
8020-4*
8037-1*
8037-2*
8043-1
8052-1
8052-2
-
8265
Address
nppr nark A ClaremonttNE cort
Islip & Blacker(NW cor)
347 + Terry(NW cor)
25 +Terry(SE cor)
Crooked Hill+495+Vanderbilt+
Saatikos Pkwv
Commerce Dr+Adams Ave
Plymouth Blvd+25(NW cor)
Oser Ave+Pkwy Dr S Serv Rd
25A+Thompfinn Hill RdfNW cort
, Product
In Tank
(2]
SU
D
SU
R
D
U
U
SU
R
U
SU
R
D
R
D
U
SU
R
U
u
Products
on Site
G.W
G.D.K
G,D
G.H.W
G,D,H,L.W
D
G,H,W
U
G.D.W
Leaks
on Record
N
D/86
Suspected
Y
Offsite TCE
(51
N
N
N
N
Depth to
Ground-
water(3)
27.0
39.5
20.0
20.9
92.0
110.0
35.0
161.0
112.0
Depth to
Ground-
water^
shallow_
shallow
shallow
shallow
deep
deep
shallow
deep
deep
Site
Age
(vrsl
15
25
27
28
7
7
15
7
75
Date
Old tanks
Installed
1972
1962
1960
1959
1980
1980
1972
1980
1912
Date
New Tanks
Installed
1981
1983
1984
1984
1980
1980
1981
1980
1985
Tank
Type
Fiber
Fiber
Fiber
Fiber
Fiber
Fiber
Fiber
Fiber
Fiber
STIP 3
STIP 3
STIP 3
Fiber
Fiber
STIP 3
Fiber
Fiber
Fiber
STIP 3
Fiber
Isolated
Tank?
N
N "
N
N
N
N
N
N
N
N
;-,-; N
N
N
N
Y
N
N
•» N
;•.. Y
:. N
(1) Known or suspected leak sites denoted by asterisk
(2) Key: G=Gasoline
R=Regular
U=Unleaded
SU=Super Unleaded
D=Diesel
K=Kerosene
H=Heating Oil
L=Lube Oil
W=Waste Oil
(3) Depth to groundwater in feet below land surface.
(4) Groundwater deeper than 50 feet is designated as "deep".
(5) Suffolk County Officials report offsite release of
trichloroethylene (TCE) to groundwater in vicinity
of site 8043.
-------
"2.2 TESTING METHODS •'.-**• ,,,^-'' -:-'' ' ' '"
Background total hydrocarbon concentrations were measured in the U-tubes
by three methods. In order of performance these methods include a top-of-
casing measurement, downhole measurement, and time-domain concentration
measurement while pumping at a high discharge rate. The primary analytical
equipment used was a Photovac Model 10S30 dual-column gas chromatograph. For
comparative evaluation of the instruments themselves, a Photovac TIP and HNu
Model PI-101 were also used in each method. The chromatograph was not used
for the top of casing measurement.
The construction characteristics of the U-tube and pumping times and
volumes for each U-tube are presented in Table 2-2. The style and quality of
installations varied, including one site with water-flooded 2-inch diameter
steel risers (#1072), two uncapped risers and one riser (#8037-1 and #8037-2)
constructed of perforated casing (#8052-3).
Downhole Background Measurement Method
The procedures for downhole measurement of background soil vapor concen-
trations in U-tubes developed during the study are detailed below.
Field equipment included the following:
Mechanical Packer (plumber's 4-inch wing-nut test plug)
1-cfm vacuum pump
1-liter tedlar sampling bag
30-foot teflon 1/8" O.D. tubing
Swagelok fittings to reduce pump intake to 1/8" O.D. tubing
25-foot plumber's snake
Photovac Model 10S30 gas chromatograph, Photovac Model TIP-I and HNu
Model PI-101 photoionization detectors
Calibrant gas (57 ppm isobutylene and 200 ppb BTX)
Centralizer
Powerful flashlight
Mirror
2-3
-------
Table 2-2. U-Tube Characteristics
and Test Parameters.
ro
u-
Tube#
m
1072
5036-1*
5036-2*
5036-3* '
8020-1*
8020-2*
8020-3*
8020-4*
8020-5*
8037-1*
8037-2*
8037-3*
8043-1
8043-2
8049
8052-1
8052-2
8052-3
8054
8265
UTube
Top Size
(inches)
2
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
U Tube
Capped
Y
N
N
Y
Y
Y
Y
Y
Y
N
N
Y
Y
Y
Y
Y
Y
Y
Y
Y
Perforations
to Surface
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Y
N
N
U Tube
Flooded
Y
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Incline
Length
(ftt
20
20
20
21
32
16
32
32
18
18
18
0
0
20
26
26
26
16
25
Riser
Length
-------
•Equipment Preparation: i . .:- -;;- ;; ...^y.^-~!
The background measurements were made downhole through 1/8" tubing. This
size was required to minimize the interval volume and concomitant flushing
times between sites. To prevent the tubing from snarling inside the U-tube,
the tubing was taped to the plumber's snake at 1 or 2 foot intervals. A
centralizer was attached to the end of the snake 1 to 2 centimeters above
the tubing inlet. The purpose of the central izer was to lift the tubing
intake off the bottom of the U-tube where several millimeters of condensation
were frequently encountered.
Testing Procedure:
The elbow and sump risers (Figure 1-2) were visually identified with the
aid of a flashlight or mirror. To reduce vapor advection and resulting
dilution by surface air, both risers were never left uncapped at the same
time. The risers were also visually inspected for flooded conditions. The
top of the sump riser was firmly sealed with a mechanical packer. If the
risers were not flooded, the snake was passed down the elbow riser to the
mid-point of the inclined section of the U-tube (usually 16 to 20 feet above
snake length). The tubing intake was thus positioned directly below the
center of "the tank. For comparison, measurements were also taken with the
intake positioned at the elbow at sites 8020 (suspected leak site) and 8037
(known leak site). The riser opening was immediately recapped to prevent
dilution by surface air.
The pump's intake and discharge ports were then connected to the 1/8-inch
tubing and to a 1-liter tedlar gas sampling bag, respectively. The pump was
not able to discharge at its rated capacity due to the restriction of the
small diameter tubing. When approximately i liter of gas was collected, the
bag was disconnected and the pump was switched off. The bag was then connect-
ed alternately to a calibrated TIP-I and HNu PI-101 and concentrations record-
ed in ppm. The bag and tubing were flushed with ambient air between measure-
ments, testing with the TIP-I for cross-contamination.
2-5
-------
Syrin'ge samples were taken from a^septum tee mounted!--upstream of the pump
intake and injected into the 10S30 chromatograph. The chromatograph was used
in the following configuration:
• flow rate - 10 milliliters per minute
• back-flush switching time at 50 seconds
t four-foot CSP-20M analytical column
• five minute analysis time
The detection limit for aromatic fuel components in this mode is approximately
1 ppm. Injection volumes were varied between 0.01 to 1.0 ml depending on
concentration indicated by the TIP. To avoid overloading the 10S30 detector
and column, smaller injections were used when the TIP indicated high concen-
trations.
For five of the seven sites with multiple U-tubes, as many U-tubes were
tested as time allowed. After removing the snake from each elbow riser, the
riser cap was carefully replaced to avoid downhole contamination or vapor
dilution.
Time Domain Background Measurement Method
Immediately following the downhole measurement, the 1/8" tubing was
removed and disconnected from the pump. The opposite end of the U-tube
remained sealed. The elbow riser was quickly fitted with a second mechanical
packer having a i-inch hose-barb which was connected to the 1 cfm pump by a
i-inch I.D. Tygon vacuum hose. A septum tee was installed near to the test.
plug. The entire U-tube-could be pumped, thus drawing soil gas through the
inclined perforated section, while periodic samples for the 10S30 were
obtained with a syringe from the septum tee. The pump was briefly switched
off for each syringe sample to avoid negative pressures in the syringe barrel.
The pump discharge was continuously measured with the TIP and HNu. The
flow to the TIP and HNu was reduced to an instrument-compatible rate by means
of a 5-port manifold. The pumping rate was monitored with a Gilmont floating-
ball type gauge. Due to the U-tubes1 very large diameter, the pump was able
2-6
-------
"to pump without restriction at its rated capacity of approximately 1 cfm (30
liters per minute).
Instrument Calibration Procedure
The 10S30, TIP and HNu were calibrated to a 57 ppm isobutylene standard
on a daily basis. All concentrations in this report are given as ppm
isobutylene.
First, the instruments were zeroed with ultra pure air from the same
cylinder used for 10S30 carrier gas. A tedlar gas sample bag was then filled
with isobutylene standard gas. The TIP and HNu were then alternately cali-
brated to the isobutylene and rezeroed twice. A check for syringe background
contamination was run for the 10S30 prior to isobutylene standardization.
A 200 ppb benzene/to!uene/xylene (BTX) gas standard was provided by
Suffolk County to aid the interpretation of chromatographic fuel product
signatures. The BTX standard was also used to calculate the 10S30 detector
sensitivity for isobutylene relative to benzene, toluene and xylenes. The
ratios of concentrations (sensitivity coefficients) reported as isobutylene to
concentrations of the actual compounds are listed below.
Benzene 0.94
Toluene 1.07
Xylenes 0.36
These values indicate that although benzene and toluene are reported within 6%
of their true concentrations, because of the 10530's low sensitivity to
xylene, reported concentrations of xylene are much lower than their true
values. A true xylene value can be obtained by dividing the reported value by
a 0.36 sensitivity coefficient. Xylene was encountered in only a few of the
U-Tubes in this study and therefore this problem was insignificant.
2-7
-------
-------
SECTION 3
RESULTS
3.1 DISCUSSION OF TOTAL CONCENTRATION
The total petroleum hydrocarbon concentration measured in 20 U-tubes are
summarized in Table 3-1. The known or suspected leak sites, denoted by
asterisks, clearly show the highest concentrations. Concentrations ranged
from below the detection limit to greater than 2200 ppm as isobutylene.
The complete pumping concentration data are presented in Appendix B,
showing the calculated concentration for each compound and sum total concen-
tration of all compounds detected. The maximum value from Appendix B for each
U-tube appears in Table 3-1. No TIP data were available for sites 1072, 5036
and 8265 because of low instrument battery conditions. No downhole data are
available for site 1072 because of flooded conditions and the inability to
identify the elbow riser in the 2-inch diameter tubing.
In general, the mid-point downhole TIP reading approximates the TIP
pumping maximum reading; however, the 10S30 downhole readings are generally 20
percent lower than the 10S30 pumping maximum readings.
Top-of-casing readings prove to be poor indicators of true soil condi-
tions as they were greatly influenced by wind conditions. For example, very
small top-of-casing readings and very large pumping and downhole readings were
obtained at U-tubes 5036-1 and 8020-1. It is significant that both of these
U-tubes are at known leak sites.
The patterns of variation which concentration followed with time during
pumping appear to be dependent on the general concentration level for the
U-Tube being measured. At high concentration values, the concentration level
stabilizes somewhat at approximately 10 minutes (approximately 3 times the
internal volume of the U-tube) (see Figure 3-1). For sites with moderate and
low concentrations, no apparent plateau was reached after 30 minutes of
pumping (see Figure 3-2 and 3-3).
3-1
-------
Table 3-1. Summary of Background Concentration
in U-Tubes.
u-
Tube#
1072
5036-1*
5036-2*
5036-3*
8020-1*
8020-2*
8020-3*
8020-4*
8020-5*
8037-1*
8037-2*
co 8037-3 .
1X5 8043-1(3)
8043-2(3}
8049
8052-1
8052-2
8052-3
8054
8265
10S30
Midpoint
iPPml —
f3\
- lgl .
373.00
645
4 no
1^3
758
730
513
365
fyAc
^40
11.9
6.8
0
31.09
0(4)
0
.
3.44
TIP
Midpoint
fnnm)
1HK"" .
-
1142
1237
840
424
pop
26
14.2
7.9
-
HNu
Midpoint
(ppm)
50
210
190
165
155
140
12.6
11.1
3.3
0
10S30
Elbow
(ppm)
-
547
599
445
222
10.8
OFFSCALE
OFFSCALE
_
-
-
TIP
Elbow
(ppm) ._
-
927
855
623
311
180
1274
1136
1050
-
-
-
HNu
Elbow
(ppm)
• ~
200
200
172
150
100
0
0
0
-
-
-
10S30
Max TIP Max HNu Max
(ppm)(5) (ppm) (ppm)
???
692
>2201
OFFSCALE
1180 1300 -.
-
17.7 15
1 1 .3 9.3
.3 l.b
67.4 56.7
80.3 35
0 2.7
0.52 1.6
5.88
112
142
49
150
-
14.2
8.7
4C
•3
35
32
1.3
1,5
6.5
TIP Top
of Casing
(ppm)
-
-
84
130
270
14.5
140
1200
126
696
8.5
0
7 5
' ••J
6.5
2
6.6
0
-
HNU Top
of Casing
(ppm)
1
1
50
40
70
15
40
9.5
13.6
11
65
8
8.8
1
4
4
0
0
0
o
(1) Known or suspected leak sites in boldface.
(2) Blank spaces indicate measurement not taken.
(3) Suffolk County officials report offsite release of TCE to groundwater in vicinity of site 8043.
Concentrations measured in 4" PVC vapor wells.
(4) Injection volume too small = .02 ml. Detection limit approximately 10 ppm.
(5) Maximum readings for Photovac 10S30, Photovac TIP and HNu measured while pumping continuously at 1 cfm.
See Appendix B for list of all concentrations measured during pumping.
-------
e-e
CONCENTRATION IN PPM
Id
n>
CO
7^ TJ
§i
S -o
o ca
-s
CO ~J-
(/) fD
-a
a> •<
n a>
rt- -5
fD to
a. c
CO
fD O
0) O
7T 3
o
CO fD
fD
<-l-
o
O
rf
to
O
-S
CONCENTRATION IN PPM
Concentration in ppm
c
1
"H. o "
3
g Time In Mil
i0'
CO
>
<
1 1 § § 1 1 1
' "^
** +
GO 00 00
IM
i
r-i
i i
i
i
i
>
00
2
(D
•o
S
-------
CONCENTRATION IN PPM
(D
CO
ro
-"• £Z
rt- 3
3"U
O CQ
Q.
fD — \
-s -••
to 3
<-*• fD
fD
co ro
o -s
—i.
— ' c:
I 10
CD
5U o
(/) O
3
ro o
cu ro
o 3
7T rt
to -s
-s o>
O rt-
c -••
3 O
O- 3
o -o
O — '
3 O
O c+
fD co
3
r+ -h
-5 O
CU -5
c-l-
o' O
3 3
to I
• r~
fD
CD
co
t-t-
fD
to
CONCENTRATION IN PPM
CONCENTRATION IN PPM
8 § 8 S
8
CONCENTRATION IN PPM
-------
S-E
CONCENTRATION IN PPM
-s
tt>
CO
i
CO
3-- -a
I— 3
o ia
GO -"•
o 3
I <
CD tt>
BJ -S
CO CO
ai
o o
7ST O
IQ 3
-S O
O fD
£Z 3
3 r*-
a. -s
a>
O e-t-
O -J-
3 O
O 3
n>
3 -O
r+ — '
-s o
B> ri-
ch CO
o' -h
3 O
to -s
O
3
CD
CO
.1*
rh
CD
CO
O
= ro
m o
ill
(O (O 08
-------
••" At low concentrations, measurements from the three instruments are in .
fair agreement (see Figure 3-3). However, the HNu did not perform- linearally
with the other instruments above approximately 50 ppm. Figure 3-4 illustrates
the linear agreement of 10S30 and TIP measurements and the non-linearity
between the HNu data and with TIP data above the 50 ppm concentration level.
A correlation is suggested between depth-to-groundwater and concentra-
tion. Figure 3-5A shows the distribution of groundwater levels as well as
highest concentration measured at each site. Note the break in distribution
at about 50 feet below land surface. Among non-leak sites, a fairly good
correlation is observed between total concentration and depth-to-groundwater,
with concentration exponentially decreasing with depth-to-groundwater. The
fact that all leak sites were located in shallow groundwater areas is purely
coincidental, therefore leak sites are not plotted in Figure 3-5B.
The time that a site has been in service for underground fuel product
storage (site age) did not correlate with background soil vapor concentration
as well as depth-to-groundwater (see Figure 3-6). However, if the 75 year
point is removed from the dataset, a general upward direct correlation is
observed. This trend may be ascribed to such factors as small unreported
overflows during delivery and dispensing which could cause a slow accumulation
of product in the soil.
The distribution of soil-gas concentration at sites with multiple tanks
and U-Tubes can help identify leaking tanks. For example, a leak was suspec-
ted at Site 8020 where five tanks (8020-1 through 8020-5) have been placed
side by side with their centers spaced ten feet apart. Concentration drops
steadily with distance from 758 ppm at 8020-1 to 245 ppm at 8020-5. A former
or existing leak at 8020-1 is clearly indicated by this distribution, assuming
that concentration does not continue to increase away from the tank cluster.
A leak was verified at this site by the county.
3.2 VARIATION IN CHEMICAL COMPOSITION
The unique chemical compositions of fuel products are identifiable by
their chromatographic signatures which are defined by characteristic peak
shapes, relative peak areas, and retention times for each chemical component.
3-6
-------
Correlation of All TIP vs. All Photovac Data
2000
T
200 400 600 800 1000 1200
Concentration Measured by 10S30 (ppm)
Correlation of HNu vs. TIP Data
100 200 300
Concentration Measured by HNU (ppm)
Figure 3-4. Scattergrams comparing performance of Photovac
10S30 TIP and HNu.
a. Note good linear fit of TIP and 10S30 data.
(Top-of-casing readings removed.)
b. Note exponential correlation of TIP and HNu data,
(Top-of-casing and outlying zero HNu readings
removed).
3-7
-------
a)
(0.52)
(5.88)
(1.3)
(17.7)
(>2200), Leak site
(80.3)
(222)
Offscale (1274 by TIP), Leak site
(1180), Leak site
0 100 200
Depth to Groundwater In Feet Below Land Surface
b)
300-1
E
£200-
,=
s
* 1
3*
100
#1072
^9
\ \ #8265
#8043j^\i
#8054
0 100 200
Depth to Groundwater in Feet Below Land Surface
Figure 3-5. Depth to Groundwater and Soil-Gas Concentration
at U-Tube Sites:
a. Depth to Groundwater for All Sites Showing Maximum
Soil-Gas Concentration Measured by 10S30 in
Parentheses.
b. Depth to Groundwater Versus Soil-Gas Concentration
at Non-Leak Sites.
3-8
-------
o
o
u
SITE AGE VS. CONENTRATION IN SOIL VAPOR
3000
a.
Q.
5 2000 -
1000-
G
B
20 40 60
SITE AGE IN YEARS
80
Figure 3-6. Site Age Versus Soil Gas Background
Concentration Scattergram.
3-9
-------
(0.6)
(0.9)
Benzene
Toluene
(0.35)
tonrt-f HUH
MW.TSIS «
O*RT smo
ruDTTER otunr
IWM.TSIS TIPt
CTCLC Tine
JUL.T
s
l an/mn
ia.1 £••
STOP t
twiru RUN
IWOCTSIS «
cnotT srtio
fLOTTCK OtLI«T
fittncTsis rinc
CTCLi TIBS
JULT 33
31
t «r1/I1:n
li.9 $••
3M.(
a K:n
run
33
A. BTX Standard
B. Site: 8052
Unleaded
(0.4)
(0.6)
0.4)
0.55)
JULT 32 IS»7
Id* JULY 21 1M7
IWM.TSIC • 10
CIMIT SrCtO 1 .(VTOd
run ten esukT u.§ s..
tywCTtje rut* •aw.* «••
CTCLC rinc a A>*
. KNXLTStS «
OlIWT STUD
PUITTCK DCUrr
WM.TSIS TIHK
CTO-I TIM
TCHPOKITIM
II. • !••
3M.* S..
• nm
C. Site: 1072
Super Unleaded
D. Site: 8052
Regular
Figure 3-7.
Chromatograms of fuel products: peak retention
time in minutes in parentheses. Samples B5 C,
and D obtained from fill pipes of actual fuel tanks,
3-10
-------
"-the chromatpgraphic signatures of the, soil-gas samples.;--from U-Tubes varied
significantly with site location, different U-Tubes within particular sites,
and pumping time.
Chromatograms of vapor samples obtained from the fill pipes of under-
ground storage tanks containing unleaded, super unleaded and regular fuel are
compared to the signature of a benzene/toluene/xylene standard in Figure 3-7.
Concentrations of benzene, toluene, and xylene in the standard (Chromatogram
A) are nearly equal, however, it appears by comparison with Chromatograms B,
C, and D that -actual fuel products contain low levels of toluene and xylene
relative to benzene. These observations are consistent with previous site
work at refineries performed by Kaman.
Considerable variation in chemical composition of soil-gas is observable
for the same product measured at different pumping times and different loca-
tions in soil-gas (see Figure 3-8). The only product known to have leaked at
Site 8020 was diesel, however, Chromatograms E and F represent a noticeable
variation in samples from the same U-tube taken 10 minutes apart. Three
casing volumes were purged during this period. Note the increase in peak
height of the first peak with increasing pumping time. Chromatograms G and H
depict variations in relative peak heights at two separate diesel spill sites.
Variations in the composition of soil gas are also observed in non-leak
sites with very low background concentrations (see Figure 3-9). Chromatograms
I and J, obtained beneath two different tanks at the same site demonstrate
differences in relative concentrations (peak heights) of the same three
compounds. Chromatogram K, representing a soil gas sample taken above a known
TCE groundwater plume with an off-site source, depicts a second peak shape and
retention time that contrasts with the petroleum product background signatures
of Chromatograms I and J. TCE coelutes with other compounds in the second
peak causing the unusual peak shape in Chromatogram K.
3-11
-------
-__ (0.3)
— (0.5)
(0.6)
SWBT
(0.3)
. .(0.5)
(0.6)
.STOP t 258.7
WPPLC KUH
IWN.TSIS •
CM«T SPUD
rUJTTEK OCLFT
CWN.TSIS Tine
CTCLC Tine
TEnPEMTUM
JULY 24 lit?
23
1
.twin
E. Site: 8020-1
.STOP * 3ee.a
WWPW MM
WM.YCIS * 24
CtW*T SPUD 1
PLOTTCK D€U«T !••• !••
IWM.TSH Ttr« M».« s>*
CTCLE Ttnc • "'A
JULY 24 1M7
F. Site: 8020-1
sr-
(O.A)
(0.6)
(0.5)
(0.6)
* .a?, i
; IBM JULY 21 1917
;» at
OMIT SPIED i »n/nifi
PUDTTIK Oturr !••• f»
r*w.Ysic Tine SM.I s*»
CTCLC Tine • nm
33
G. Site: 5036
STOP t
».»
KHN.TSIS *
CHMIT SPEED
PLOTTfK DtU«T
WW.YSIS Tine
CTCLC TIK
JULY 24 19*7
27
i •rvnm
!••• Set
•
57
dm
H. Site: 8020-2
Figure 3-8.
Variation in Soil Gas Chromatographic signatures at
known or suspected diesel leak sites: Chromato-
grams E and F represent samples from the same
U-tubes taken ten minutes apart during pumping.
Three casing volumes were purged during this
period. Note the increase in relative peak height
of the first peak with pumping time. Chromatograms
6 and H depict variations in relative peak heights at
two separate spill sites.
3-12
-------
SIIWT.
=«— (0.3)
(0.5)
(0.6)
OHM.TSIS • 9
OWKT SMID t
WWLYSIE TIC* 3M.( G*«
CYCLE Tint • rt'n
TOIPtWITUMC 39
?IOP S 213. 1
SWTLE IBM
KNM.TSIC •
G#WT SPEED
ruJTTtn oeLurr
KHM.TSIS Tint
CTCLC Tint
JULT 32 IM7
J. 8052-1
17
I
3M.« S»t
» dm-
39
Note changes in relative
peak heights.
I. Site: 8052-2
., _ (0.4)
(0.9)
5 TOP i 188.9
«m.t n*i JULT
MM.TSIS C 14
CXMIT snco i •nxn
fUJTTE* OCUHr !••• «••
WM.TSIS Tir* 3M.t St»
CTCLC rine • nm
a?
K. Site: 8043-1
Offsite TCE
Figure 3-9. Variation in Soil Gas Chroma tographic Signatures at
non-leak sites. Chroma tog rams I and J, obtained
beneath two different tanks at the same site,
demonstrate differences in relative concentrations
(peak heights) of the same three components.
Chromatogram K, representing a soil gas sample
taken above a known TCE groundwater plume with an
offsite source depicts a peak shape and retention
time that contrasts with the petroleum product
background signatures of Chromatograms I and J.
3-13
-------
-------
, SECTION 4 .-.*•?.i
CONCLUSIONS AND RECOMMENDATIONS
4.1 BACKGROUND CONCENTRATION
1. Soil vapor concentrations at sites with leak histories exceeded 122
ppm. However, measurements for this study were taken months after
the leaks had occurred. The 122 ppm measurement was taken in a
U-tube that was approximately 50 feet distant from the location of
the former leaking tank. Measurements taken closer to tanks with
more recent kflown leak histories had off-scale readings exceeding
2000 ppm. The concentrations may have been on the order of 10,000
ppm, had equipment capable of such measurements been used. There-
fore, Kaman Tempo feels that an alarm level much greater than 500
ppm may be acceptable for detecting leaks as they occur. The actual
alarm"level could be set lower for sites with lower background vapor
concentrations.
2. Background concentrations appear to be an order of magnitude higher
in areas of shallow groundwater.
3. Background concentrations are often influenced by non-leak events
and conditions, e.g. off-site TCE spill that resulted in a ground-
water contaminant plume at Site 8043.
4. The chromatographic signatures of the soil-gas samples from U-Tubes
varied significantly with site location, different U-Tubes within
particular sites, and pumping time. Therefore, care should be used
in determining which tank at a site is leaking based on chemical
composition alone. Each tank should be monitored separately and
leaks identified on the basis of concentration level.
5. Older sites (sites that have been in service for .underground fuel
storage for many years) generally have higher background concentra-
tions than do younger sites.
4-1
-------
•'"•" 6. 'Isolated sites (sites .greater than 600 feet.:di.-starit from other tank
sites) had the lowest background concentrations of those measured
(Table 4-1). The alarm level could be. set at a lower level at such
sites than for non-isolated sites.
7. Background concentration level appears to be independent of tank
construction material.
4.2 METHODOLOGY
1. U-tubes can be used effectively to monitor the concentration of fuel
product components in soil-gas in granular underground storage tank
backfill.
2. Elevated concentrations measured in U-tubes can indicate the occur-
rence of tank leaks.
3. The most accurate representative background concentrations are
obtained by pumping a minimum of nine casing volumes (30 minutes at
1 cfm) from the U-tubes (accuracy is based on stabilization of
concentration with time). However, this method is time intensive.
4. Many U-tubes can rapidly be measured in one day by the downhole
method to yield concentrations within 20 percent of the
concentrations measured by the pumping method. This accuracy should
be sufficient for leak detection purposes.
5. The top-of-casing method does not provide reproducible or represen-
tative information and should not be used in a formal monitoring
program.
6. Concentrations measured with the HNu PID-101 do not correlate
linearly with those measured by the Photovac 10S30 or TIP (based on
comparison of data from a single instrument of each model).
4-2
-------
Table 4-1. Isolated sites show the lowest
background concentrations.
u-
Tube#
m
1072
5036-1*
5036-2*
5036-3*
8020-1*
8020-2*
8020-3* •'
8020-4*
8020-5*
8037-1*
8037-2*
8037-3*
8043-1
8043-2
8049
8052-1
8052-2
8052-3
8054
8265
Isolated
Tank?
N
N
N
N
N
• N
N
N
N
N
N
N
N
N
Y
N
N
N
Y
N
10S30
Midpoint
(ppm)
- (Z\
373.00
645
123
758
730
513
365
245
-
-
.
11.9
6.8
0
31.09
0(4)
0
0
3.44
TIP
Midpoint
(ppm)
.
-
-
.
1142
1237
840
424
222
-
-
-
26
14.2
7.9
-
-
.
.
-
(1) Known or suspected leak sites in boldface.
(2) Blank spaces indicate measurement not taken.
4-3
-------
4.3 CONSTRUCTION DESIGN AND INSTALLATION,QUALITY
1. Inconsistent U-Tube construction design and installation quality
were observed in this study resulting in erratic monitoring condi-
tions. Riser caps must provide a good atmospheric seal and should
be installed sufficiently below grade to allow clearance with the
monument lid. Risers must be constructed of non-perforated casing.
2. Design considerations should include locking caps and surface seals
to prevent tampering or inadvertent contamination by surface spills.
3. Smaller diameter pipe and elimination of the sump riser would
obviate the long pumping times or large pumping rates needed for
monitoring of 4-inch casing.
4. Because high background concentrations can persist in soil gas for
longer than two years after a leak, e.g. Site 5036, a monitoring
system cannot function properly unless all contaminated soil is
excavated before reinstalling tanks at a leak site.
4-4
-------
APPENDIX A
CALCULATION OF RELATIVE DETECTOR SENSITIVITIES
FOR ISOBUTYLENE, BENZENE, TOLUENE, AND XYLENE
-------
-------
Apoendix A. Calculation of Relative Detector Sensitivities
for Isobutylene, Benzene, Toluene and Xylene.
Date: 7/24/87
Isobutylene STD Cone, (ppm) = 57
Isobutylene STD inj. vol.(ml) = 0.02
Isobutylene STO Gain » 2
Isobutylene STD Area (sqmm) = 20
K= 0.114
Where K = (STD Cone. * STD inj volume * STD Gain) / STD Area
Cone, of Sample = (K * A)/ (V* G)
Where A,V and G are sample Area, Volume, and Gain, respectively.
Compound
Benzene
Toluene
Xylenes
Actual
Concentration
(DDirri
0.224
0.214
0.223
Injection
Volume
/mil
0.7
0.7
0.7
Gain
50
50
50
Peak
Elution Time
(min)
6
9
19.5
Peak
Area
(sqmml
65
70.5
25
Concentration
Computed as
Isobutylene
0.21
0.23
0.08
Relative sensitivity'
0.94
1.07
0.36
Compound Note:
Benzene Actual concentrations of BTX were 224,214, and 223 ppb.
Toluene Benzene and toluene have early identical detector sensitivities as isobutylene.
Xylenes Xylene detector sensitivity is much lower.
* (Concentration as isobutylene)/(Concentration as BTX)
-------
-------
APPENDIX B
CALCULATIONS OF CONCENTRATIONS
FROM PHOTOVAC 10S30 PEAK AREAS
-------
-------
Appendix B,. Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page 1
U-Tube 1072
Product SU
Date 7/21/87
Isobutylene STD Cone, (ppmj =
STD inj. vol.(ml) =
STD Gain «
STD Area (sqmm) =
Concentration
INJ Vol
fmn
not run
1.00
1.00
0.02
0.02
0.02
:;'.' Peakl
But. t Area
-Gain (mini (samrrrt
71*
'2
2
2
2
4
3.5
3.5
3.5
3.5
189
384
34
40
41
57
0.02
2
24
Peak 2
But. t
(mini
0.095
Where K
•. (STD Cone. * STD inj volume * STD Gain) / STD Area
Area
Cone, of Sample . (K * A)/ (V*G)
Where A,V and G are sample Area, Volume, and Gain, respectively.
Peak3
Elut. t Area Total
(sgmmi concentration (mhiL. JaammL Concentration
8.98
18.24
80.75
95.00
97.38
6
6
6
22
28
48
0.00
0.00
52.25
66.50
114.00
20
20
20
20
40
2.5
5
4.5
0.00
1.90
5.94
11.88
10.69
8.98
off scale
138.94
173.38
222.06
Measuring
Point/
Elapsed
Time
midpoint
0
16
21
25
29
-------
U-Tube 5036-1
Product D
Date 7/21/87
INJVol
(mu —
0.02
0.02
0.02
0.02
0.01
0.01
0.01
0.01
0.01
0.01
. ;2
2
2
2
2
2
2
2
Appendix B.. Calculation of Concentrations from Photov
Isobutylene STD Cone, (ppm) - 57 K- 0. ^
STD inj. vol.(ml) - 0.02 Where K = (STD Cone.
STD Gain - 2
STD Area (sqmm) = 29 cone. p
Peakl P"*2 PF^t3
Elut.t Area Elut. t Area Elut.t
(mini (sorting nnnrentration (mini isgmml. carOTntration. -imiDL.
4
3.5
3.5
3.5
3.5
3.5
3.5
3.5
3.5
3.5
55
17
68
71
50
32
30
47
42
51
108.10
33.41
133.66
139.55
196.55
125.79
117.93
184.76
165.10
200.48
5
5
5
5
5
5
5
5
5
5
35
7
27
61
24
17
17
18
15
22
68.79
13.76
53.07
119.90
94.34
66.83
66.83
70.76
58.97
86.48
6
6
6
6
6
6
6
6
6
6
ac 10S30
STD inj v
\)/ (V*G)
rniple Aree
Area
(sqmml _
100
38
80
120
102
96
72
52
65
99
Peak Areas.
olume * STD Gain) / STD Area
\, Volume, and Gain, respectively.
Total
rnncontratiort finncentratlon
196.55
74.69
157.24
235.86
400.97
377.38
283.03
204.41
255.52
389.17
373.45
121.86
343.97
495.31
691.86
570.00
467.79
459.93
479.59
676.14
Page 2
Measuring
Point/
Elapsed
Time
Midpoint
0
2
6
10
14
17
22
27
32
-------
U-Tube
Product
Date
INJ Vol
(ml)
0.01
0.02
0.02
0.01
0.005
5036-2
S
7/21/87
• -Gain
.'2
"'3
':?
2
2
Appendix B. , Calculation of Concentrations from Photovac 10S30 Peak Areas.
Isobutylene STD Cone, (ppm) - 57 K- 0.07862068
STD inj. vol.(ml) - 0.02 Where K » (STD Cone. * STD inj volume * STD Gain) / STD Area
STD Gain - 2
STD Area (sqmm) - 29 Cone, of Sample - (K * A)/ (V*G)
Where A,V and G are sample Area, Volume, and Gain, respectively.
Peak 1 Peak 2 Peak 3
Elut. t
(min)
4
4
4
4
*
Area
(sqmm)
52
50
46
50
280
Concentration
204.41
98.28
90.41
196.55
2201.38
Elut. t
(min)
6
6
6
6
Area
(sqmm)
112
105
175
50
Elut. t
Concentration (mini
440.28
206.38
343.97
196.55
0.00
Area
(sqmm) Concentration
0.00
0.00
0.00
0.00
Total
Concentration
644.69
304.66
434.38
393.10
2201.38
Pages •
Measuring
Point/
Elapsed
Time
midpoint
0
2
16
25
BOLDFACE TOTAL CONCENTRATIONS ARE APPROXIMATED FROM OFFSCALE PLOTS
-------
* •*
Appendix B. Calculation of Concentrations from Photovac 10S30 Peak Areas.
U-Tube 5036-3
Product R
Date 7/21/87
INJ Vol '
ll'IU VVI
/ml\ f^flln
0.10 2
Isobutylene STD Cone, (ppm) » 57
STD inj. vol.(ml) = 0.02
STD Gain - 2
STD Area (sqmm) - 29
Peak 1 Peak 2
Elut. t Area Elut. t
imin\ fcnmnri Concentration lm\n]
3.5 312 122.65
* v-
Page 4
K- 0.07862068
Where K - (STD Cone. * STD inj volume * STD Gain) / STD Area
Cone, of Sample » (K * A)/ (VG)
Where A,V and G are sample Area, Volume, and
Peak 3
Area Elut. t Area
(sgrnrn) Concentration (rnin) isommi Concentration
o.oo o.oo
Gain, respectively.
Total Measuring
Concentration Point/
122.65 midpoint
-------
Appendix B.. Calculation of Concentrations from Photovac 10S30 Peak Areas. Page 5
U-Tube 8020-1 Isobutylene STD Cone, (ppm) - 57 K= 0.114 .
product D STD inj. vol.(ml) - 0.02 Where K = (STD Cone. * STD inj volume * STD Gain) / STD Area
Date 7/24/87 STD Gain- 2
INJ Vol
fmh
^iTIIj
0.01
0.01
0.01
0.01
• • fiain
2
'•'2
2
2
Peakl
Elut. t
3
3
3
3
3
STD
Area
i so mm i
16
18
18
49
42
Area (sqmm) -
Concentration
91.20
102.60
102.60
279.30
239.40
20
Peak 2
Elut. t
(mini
6
6
6
6
6
Cone, of Sample - (K * A)/ (V'G)
Where A,V and G are sample Area, Volume, and
Peak 3
Area Elut. t Area
(sqmrm
80
115
70
158
162
Concentration (min)
456.00
655.50
399.00
900.60
923.40
teomml Concentration
0.00
0.00
0.00
0.00.
0.00
Gain, respectively.
Total
Concentration
547.20
758.10
501.60
1179.90
1162.80
Measuring
Point/
Elapsed
Time
Elbow
Midpoint
0
4 -
10
-------
Appendix B. Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page6
U-Tube 8020-2
Product U
Date 7/24/87
INJVol
/ml\ '>/"isitn
inn/ 'Uaiii
0.01 . 2
0.01 !'%
Isobutylene STD Cone, (ppm) -
Peakl
Elut. t
I mm}
3
3
STD inj. vol.(ml) -
STD
Area
(samrnl—
17
28
STD Gain -
Area (sqmm) =
Concentration
96.90
159.60
57
0.02
2
20
K=
0.114
Where K - (STD
Cone, of Sample
Cone.
-(K*
* STD inj
A)/ (VG)
volume * STD
Gain) / STD Area
Where A,V and G are sample Area, Volume, and Gain, respectively.
Peak 2
Elut. t
ImM
Peak3
Area
(sqmrm
6 88
6 100
Concentration
501.60
570.00
Elut. t
fmin)
Area
teqmrm
Concentration
0.00
0.00
Total
Concentration
598.50
729.60
Measuring
Point/
Elbow
Midpoint
-------
Appendix B.- Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page?
U-Tube 8020-3
Product U
Date 7/24/87
Isobutylene STD Cone, (ppm) -
STD inj. vol.(ml) -
STD
STD Gain »
Area (sqmm) -
57
0.02
2
20
K-
0.114
Where K - (STD
Cone, of Sample
Cone.
.(K*
* STD inj
A)/ (V*G)
volume * STD
Gain) / STD Area
Where A,V and G are sample Area, Volume, and Gain, respectively.
INJVol
(nih Gain
0.01 ,_\2
0.01 .':&
Peakl
Elut. t
(mini
3
3
Area
teqmml
24
30
Concentration
136.80
171.00
Peak 2
Elut. t
(min)
Peak 3
Area
(sqmmV
6 54
6 60
Concentration
307.80
342.00
Elut. t
(min)
Area
(sqmml
Concentration
0.00
0.00
Total
Concentration
444.60
513.00
Measuring
Point/
Elbow
Midpoint
-------
Appendix B. Calculation of Concentrations from Photovac 10S30 Peak Areas. Page 8
U-Tube 8020-4 Isobutylene STD Cone, (ppm) - 57 K= 0.114
Product SU STD inj. vol.(ml) « 0.02 Where K - (STD Cone. * STD inj volume * STD Gain) / STD Area
Date 7/24/87 STD Gain - 2
STD Area (sqmm) * 20 Cone, of Sample - (K * A)/(V'G)
Where A,V and G are sample Area, Volume, and Gain, respectively. Measuring
Peakl Peak 2 Peak 3 Point/
INJVol Elut. t Area But. t Area Elut. t Area Total Elapsed
fmll -6aln fminl (sqmml Concentration (mini (sqmml Concentration (mini (samml Concentration —CgncepUatlon. limi—
0.01 :':2 3 14 79.80 6 25 142.50 0.00 222.30 Elbow
0.01 "'*2 3 29 165.30 6 35 199.50 0.00 364.80 Midpoint
-------
Appendix B.. Calculation of Concentrations from Photovac 10S30 Peak Areas. Page 9
U-Tube 8020-5 Isobutylene STD Cone, (ppm) - 57 K= 0.114
product R STD inj. vol.(ml) - 0.02 Where K - (STD Cone.' STD inj volume * STD Gain) / STD Area
Date 7/24/87 STD Gain» 2
STD Area (sqmm) - 20 Cone, of Sample - (K * A)/ (V*G)
'•••'. Where A,V and G are sample Area, Volume, and Gain, respectively. Measuring
Peakl Peak 2 Peaks P°'nt/
INJ Vol Elut. t Area But. t Area Elut. t Area Total Elapsed
_Jmll_-JBairj_^Jfflin) 'fiq™m> concentration fmini (somrm Concentration _(mini_ isflmmi concentration CpncentrpUon Time
0.10 ;;2 3 5 2.85 6 14 7.98 0.00 10.83 Elbow
0.01 ":^2 3 10 57.00 6 33 188.10 0.00 245.10 Midpoint
0.1 V2 3 42 23.94 6 135 76.95 0.00 100.89 Midpoint
-------
Appendix B. .Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page 10
U-Tube 8043-1 Isobutylene STD Cone, (ppm) - 57
Product D STD inj. vol.(ml) - 0.02
Date 7/23 STD Gain- 2
4" DIA Vapor Well STD Area (sqmm) - 21
TCE Spill Off site
Peakl Peak 2
INJ Vol
imn
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
• • Gain
.''2
''"2
2
2
2
2
2
2
Elut. t
4
4
4
4
4
4
4
4
4
Area
(samm)
20
0
21
29
31
33
34
34
36
Concentration
2.17
0.00
2.28
3.15
3.37
3.58
3.69
3.69
3.91
Elut. t
(mini
5
5
5
5
5
5
5
5
5
K-
Area
(sqmm)
0
21
0
0
0
0
0
0
0
0.10857142
Where K - (STD Cone. ' STD inj volume * STD Gain) / STD Area
Cone, of Sample - (K * A)/ (V*G)
Where A,V and G are sample Area, Volume, and Gain, respectively.
Peak 3
Concentration
0.00
2.28
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Elut. t
(mini
9
9
9
9
9
9
9
9 .
9
Area
(sqmmL
90
28
105
123
117
126
123
129
126
Concentration
9.77
3.04
11.40
13.35
12.70
13.68
13.35
14.01
13.68
Total
Concentration
11.94
5.32
13.68
16.50
16.07
17.26
17.05
17.70
17.59
Measuring
Point/
Elapsed
Time
midpoint
0
2
6
12
15
21
25
29
-------
Appendix B.- Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page 11
U-Tube 8043-2 Isobutylene STD Cone, (ppm) » 57
Product R STD inj. vol.(ml) - 0.02
Date 7/23 STD Gain- 2
4" DIA Vapor Well STD Area (sqmm) - 21
TCE Spill Offslte
Peakl Peak 2
INJ Vol
(ml)
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
' "pain
,-•''2
"'^2
•2
2
2
2
2
2
2
:J2
Elut. t
(mini
4
4
4
4
4
4
4
4
4
4
Area
(sqmm)
19
20
21
23
23
21
22
22
24
22 -
Concentration
2.06
2.17
2.28
2.50
2.50
2.28
2.39
2.39
2.61
2.39
Elut. t
(min)
9
9
9
9
9
9
9
9
9
9
K-
Area
(sqmm)
44
50
60
72
74
68
78
75
80
78
0.10857142
Where K « (STD Cone. * STD inj volume * STD'Gain) / STD Area
Cone, of Sample « (K * A)/ (V*G)
Where A,V and G are sample Area, Volume, and Gain, respectively.
Peaks
Concentration
4.78
5.43
6.51
7.82
8.03
7.38
8.47
8.14
8.69
8.47
Elut. t Area
(min) (sqmm) Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Total
Concentration
6.84
7.60
8.79
10.31
10.53
9.66
10.86
10.53
11.29
10.86
Measuring
Point/
Elapsed
Time
midpoint
0
2
7
10
14
18
24
26
31
-------
Appendix B.- Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page 12
U-Tube
Product
Date
INJVol
Sml\
^Illl^ _
0.01 .
0.5
0.5
0.5
0.5
0.5
0.5
0.5
8049
D
7/23
• Rain
.'J-2
r$2
'^
2
2
2
2
2
Isobutylene STD Cone, (ppm) « 57
STD inj. vol.(ml) - 0.02
STD Gain - 2
STD Area (sqmm) - 21
Peak 1 Peak 2
Elut. t
...
4
4
4
4
4
4
4
4
Area
fsamml
0
6
0
0
0
0
0
0
Concentration
0.00
0.65
0.00
0.00
0.00
0.00
0.00
0.00
Elut. t
(mini
9
9
9
9
9
9
9
9
K-
Area
(sqmrm"
0
6
0
0
0
0
0
0
0.10857142
Where K - (STD Cone. * STD inj volume * STD Gain) / STD Area
Cone, of Sample - (K * A)/ (V*G)
Where A,V and G are sample Area, Volume, and Gain, respectively.
Peaks
Elut. t
Concentration (mini
0.00
0.65
0.00
0.00
0.00
0.00
0.00
0.00
Area
(sqmml Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Total
Concentration
0.00
1.30
0.00
0.00
0.00
0.00
0.00
0.00
Measuring
Point/
Elapsed
Time
midpoint
0
3
6
10
17
23
30
-------
Appendix B.. Calculation of Concentrations from Photovac 10S30 Peak Areas.
U-Tube 8052-1 Isobutylene STD Cone, (ppm) - 57 K- 0.10363636
product u STD Inj. vol.(ml) - 0.02 Where K » (STD Cone. * STD inj volume * STD Gain) / STD Area
Date 7/22 STD Gain- 2
Peak 1
iNJVol Elut.t
/ml\ • " r^oin fmin^
0.02 2 4
0.02 '.'':'& 4
0.02 ':1J2 4
0.02 2 4
0.02 2 4
0.02 2 4
0.02 2 4
0.02 2 4
0.02 2 4
0.02 ;2 4
0.02 -~2 4
0.02 2 4
*
STD Area (sqmm) - 22
Peak 2
Area Elut. t
(somrrrt Concentration. fining
0 0.00 6
0 0.00 6
0 0.00 6
0 0.00 6
0 0.00 6
0 0.00 6
0 0.00 6
0 0.00 6
1 2.59 6
1 2.59 6
4 10.36 6
4 10.36 6
*
Cone, of Sample - (K * A)/ (V*G)
Where A.V and G are sample Area, Volume, and Gain, respectively.
Area
fsqmm)
12
6
15
10
11
8
10
11
15
16
22
22
Cpncentration
31.09
15.55
38.86
25.91
28.50
20.73
25.91
28.50
38.86
41.45
57.00
57.00
Peak 3
Elut. t Area
(mip) (sqmrm Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Total
Concentration
31.09
15.55
38.86
25.91
28.50'
20.73
25.91
28.50
41.45
44.05
67.36
67.36
Page 13
Measuring
Point/
Elapsed
Time
midpoint
0
3
5
8
11
15
19
23
28
31
36
*,
-------
Appendix B., Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page 14
U-Tube
Product
Date
JNJ Vol
tm\)
0.02
0.02
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.02
0.02
8052-2
SU
7/22
••"•Gain
.-!':'2
""|.2
'-12
2
2
2
2
2
2
*:2
2
2
2
Isobutylene STD Cone, (ppm) » 57
STD inj. vol.(ml) •= 0.02
STD Gain = 2
STD Area (sqmm) - 22
Peak 1 Peak 2
Elut. t
(min)
4
4
4
4
4
4
4 .
4
4
4
4
4
4
Area
{sqmm)
0
0
1.5
2.5
3
6
8
20
27
29
34
13
16
Concentration
0.00
0.00
0.78
1.30
1.55
3.11
4.15
10.36
13.99
15.03
17.62
33.68
41.45
Elut. t
(min)
6
6
6
6
6
6
6
6
6
6
6
6
6
K-
Area
fsqmmV
0
0
7
9
6
14
20
24
33
42
58
14
15
0.10363636
Where K - (STD Cone. * STD inj volume * STD Gain) / STD Area
Cone, of Sample - (K * A)/ (VG)
Where A,V and G are sample Area, Volume, and Gain, respectively.
Peak3
Concentration
0.00
0.00
3.63
4.66
3.11
7.25
10.36
12.44
17.10
21.76
30.05
36.27
38.86
Elut. t Area
(min) (samm) Concentration
0.00
0.00
0.00
0.00.
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Total
Concentration
0.00
0.00
4.40
5.96
4.66
10.36
14.51
22.80
31.09
36.79
47.67
69.95
80.32
Measuring
Point/
Elapsed
Time
midpoint
0
2
3
6
9
11
14
17
20
24
28
32
-------
Appendix B.- Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page 15
U-Tube 8052-3
Product R
Date 7/22/87
INJVol
fml\
""" .
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
Gain
;-:2
'•^2
H2
2
2
2
2
2
2
Isobutylene STD Cone, (ppm) -
STD inj. vol.(ml) -
STD Gain -
STD Area (sqmm) -
Peakl
Elut. t
(min)
0
0
0
0
0
0
0
0
0
57
0.02
2
22
K-
0.10363636
Where K - (STD Cone. * STD inj volume * STD Gain) / STD Area
Cone, of Sample . (K * A)/ (V*G)
Where A.V and G are sample Area, Volume, and Gain, respectively.
Peak 2
Area
fsamm)
0
0
0
0
0
0
0
0
0
Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Elut. t
(mini
0
0
0
0
0
0
0
0
0
Area
fsqmml
0
0
0
0
0
0
0
0
0
Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Peak 3
Elut. t Area
_Imini- Jaamml Concentration _
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Total
Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Measuring
Point/
Elapsed
Time
midpoint
0
2
6
9
13
18
23
49
-------
Appendix B. Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page 16
U-Tube
Product
Date
INJ Vol
0.10
0.10
0.10
0.10
0.10
0.10
0.10
1.00
1.00
8054
U
7/22/87
••'•Gain
. 2
'V .2
12
2
2
2
2
2
2
Isobutylene STD Cone, (ppm) - 57
STD inj. vol.(ml) - 0.02
STD Gain - 2
STD Area (sqmm) « 22
Peak 1 Peak 2
Elut. t
(mini
6
6
6
6
6
6
6
6
6
.Area
fsamm)
0
0
0
0
0
0
0
5
8
Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.26
0.41
Elut. t
(min)
9
9
9
9
9
9
9
9
9
K-
Area
(sqmm)
0
0
0
0
0
0
0
1
2
0.10363636
Where K - (STD Cone. * STD inj volume * STD Gain) / STD Area
Cone, of Sample - (K * A)/ (V*G)
Where A,V and G are sample Area, Volume, and Gain, respectively.
Peak 3
Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.05
0.10
Elut. t Area
_(min)_isflmmi Concentration _
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Total
Concentration
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.31
0.52
Measuring
Point/
Elapsed
Time
: Elbow
•.Midpoint
0
5
9
14
19
20
29
-------
Appendix B,- Calculation of Concentrations from Photovac 10S30 Peak Areas.
Page 17
U-Tube 8265
Product U
Date 7/20/87
INJ Vol
fmh
««mm.^
1.00
0.10
0.10
0.10
0.10
0.50
1.00
1.00
1.00
•".-ttain
:•:• 2
".-•2
••2
2
2
2
2
2
2
Isobutylene STD Cone, (ppm) - 57
STD inj. vol.(ml) - 0.02
STD Gain - 2
STD Area (sqmm) - 15.7
Peak 1 Peak 2
Elut. t
(m\r\]
4
4
4
4
4
4
4
4
4
.Area
(so mm}
39.7
0
0
2.5
2.5
19
28
31
28
Concentration
2.88
0.00
0.00
1.82
1.82
2.76
2.03
2.25
2.03
Elut. t
(mini
7
7
7
7
7
7
7
7
7
K-
Area
(sqrpm)
7.7
0
0
0
0
19
53
50
47
0.14522292
Where K « (STD Cone. * STD inj volume * STD Gain) / STD Area
Cone, of Sample » (K * A)/ (VG)
Where A.V and G are sample Area, Volume, and Gain, respectively.
Peak 3
Concentration
0.56
0.00
0.00
0.00
0.00
2.76
3.85
3.63
3.41
Elut. t Area
JsM- -(summX Concentration _
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Total
Concentration
3.44
0.00
0.00
1.82
1.82
5.52
5.88
5.88
5.45
Measuring
Point/
Elapsed
Time
midpoint
0
5
7
10
13
19
24
31
-------
------- |