The Snap Sampler is a passive, no-purge groundwater sampling device that collects representative samples without purging or transferring the sample at the wellhead. It works by deploying sample bottles in an open position in the well, then using a simple mechanical trigger to close the bottles in situ after a residence time of 1-2 weeks or longer. Comparison data shows the Snap Sampler produces results that highly correlate with low-flow purging and has advantages in terms of cost savings, improved data quality and consistency, health and safety benefits, and generating no purge water waste.

1. Passive, No-Purge, Sampling
Snap Sampler
with the
Know your sample
Trust your data
Mr. Sandy Britt, PG, CHG
ProHydro, Inc.
Sandy.Britt@ProHydroInc.com
1
www.SnapSampler.com

2. Snap Sampler
The is a passive,
Equilibrated Grab Sampler
• Deploy with bottles in an
open position.
• Sample after short or long
residence time in the well—
1-2 weeks or 3 or 6 months
• Simple mechanical trigger
closes bottles in situ.
• No sample transfer required
at the well head for VOCs
-No exposure to air 2

3. How the Snap Sampler works….
Insert
Insert
Push
down to
40ml 125ml set Snap
Cap
3

4. How the Snap Sampler works…continued
Hang on
Lower downhole
Insert Dock Ring
Trim
trigger
excess
Add
Snap Cap
safety
cable
tie
Secure
Attach
fitting
• Modular samplers allow up to 4
bottles per trigger
• Multiple triggers can be used for
multiple sampling depths 4

5. Passive, No-Purge, Sampling…
Natural flow-through: Naturally Purged.
Robin and Gillham (1987) natural background flow in a
moderate permeability sand flushed tracers from an isolated
screen interval in 24 hours or less. Ground Water Monitoring Review, v. 7, no. 4,
p. 85-93
Powell and Puls (1993) “passive sampling devices…could
remain open in the screen interval during the recovery
period, then be closed to the collect the sample and brought
to the surface.” Journal of Contaminant Hydrology, v12, p51-77
ASTM (2002) “Low-flow purging differs from traditional
purging…in that its use is based on the observations of
many researchers that water moving through the formation
also moves through the well screen. Thus, the water in the
screen is representative of the formation water surrounding
the screen” Emphasis Added. ASTM designation D-6771-02
USEPA-recommended LOW FLOW sampling relies
on the same natural flow through conditions
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6. The Advantages…
• FAST, EASY, HIGH DATA QUALITY.
• Fast and easy improves cost, while
high data quality sets
the Snap Sampler apart
• All critical actions take place
submerged in the well
• no well-head sample transfer
• very repeatable
• Sampling personnel do not
affect sample collection 6

7. You can Snap Sample by yourself…
…without this truck…
…and with almost none
of this equipment
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8. What analytes can be Snap Sampled?
Any--as long as you can collect enough water.
VOCs including MTBE, MEK, TMBs and 1,4-dioxane
Metals, general wet chemistry, SVOCs, PCBs,
perchlorate, pharmaceuticals, and many others.
Long analyte lists are a practical limitation.
However, much is still possible with….
• Minimum Sample Volumes (ITRC)
• Improvements in laboratory technology
Large Volume Injector 8

9. How does comparison data look for the
Snap Sampler?
Example conclusions
from independent Snap Sampler trials:
“passed with flying colors”
-US Army Cold Regions Research Lab
“more consistently representative”
-Parsons
9

10. • Very good correlations (R2=0.99+, 0.98)
• No exposure during pouring yields
slightly higher concentrations
• CVOC constituents
10
Britt, Parker, Cherry, in Prep.

11. • Very good correlation (R2 = 0.99+)
• No exposure during pouring yields slightly
higher concentrations
• BTEX MTBE CVOC 11
TN & Associates, US Navy, unpublished data

12. • Very good correlation (R2 = 0.99+)
• Non volatile shows equivalent concentrations
• Perchlorate
12
Private site, unpublished data

13. Snap Sampler vs. Low Flow
R2 = 0.99 for all analyte
comparisons to low flow
Snap Sample Concentration (g/L)
125ml
Little
Scatter 40ml
Low Flow Purge Sample Concentration (g/L)
• Very good correlation (R2 = 0.99+) for ALL comparisons
• No exposure during pouring yields slightly higher
concentrations
• VOCS, 1,4-dioxane, anions 13
Parsons, 2005, McClellan Air Force Base, Sacramento, CA

14. Low Flow vs. PDB
Low Flow vs. 3 Volume
R2 = 0.76 for VOCs R2 = 0.79 for VOCs
R2 = 0.58 for VOCs R2 = 0.99 for VOCs
Little
Scatter
3 Volume vs. PDB Low Flow vs. Snap Sampler
14
Parsons, 2005, Demonstration of No-Purge Groundwater
Sampling Devices, McClellan AFB, Sacramento, CA

15. 3 volume vs Hydrasleeve
PDB vs Hydrasleeve
R2 = 0.50 for VOCs
R2 = 0.38 for VOCs
R2 = 0.95 for VOCs R2 = 0.90 for VOCs
Less Less
Scatter Scatter
Snap Sampler vs. PDB Snap Sampler vs. 3 volume
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16. McClellan Conclusion Summary (Parsons)
“..the Snap Sampler …may be more consistently
representative of the actual VOC concentrations in
the well at the time of sample collection.”
What does better data do for you?
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17. See Data Trends Sooner…
Fewer variables for Snap: actual
Many variables for purge: actual
concentration, pump deployment position concentration, transport, analytical
variability.
variations, equipment calibration,
pumping duration, stability criteria
Discern your data trend…
requirements, wind, temperature, site
surface or ambient air contamination, • Reduce monitoring
bottle fill rate, pour technique, speed of
• Close sites sooner
bottle closure, transport, analytical
variability.
www.SnapSampler.com
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18. Cost Savings for No-Purge
Snap Sampling?
YES!
NPV Comparison
30-yr cost
$401,660
$450,000
$400,000
NPV $ (After Tax)
$350,000
10-yr cost
$300,000
$201,758
$250,000
$200,000
$150,000
30-yr cost
$100,000
$196,349
$50,000
10-yr cost
$0 $105,122
1 4 7 10 13 16 19 22 25 28
Time (Years)
Nice early Snap Sampler Well Purge
break-even
www.SnapSampler.com 18

19. Dedicated Snap Sampler Equipment?
Guarantee consistent,
Snap Samplers are dedicated
long-term, high quality
equipment that will be reused
data with a one-time
for years
expenditure.
The one-time expense is
never repeated, so your after
one event, savings is
NPV Comparison
30-yr cost
comparable to other passive
$401,660
$450,000
approaches that have minimal
$400,000
NPV $ (After Tax)
$350,000
dedicated equipment cost
10-yr cost
$300,000
$201,758
$250,000
$200,000
$150,000
Cost per well depends on may
30-yr cost
$100,000
$196,349
$50,000
factors, but can be as low as
10-yr cost
$0 $105,122
1 4 7 10 13 16 19 22 25 28
$225 at standard prices, less
Time (Years)
with bulk purchases
Snap Sampler Well Purge
www.SnapSampler.com 19

20. Snap Sampling:
• Saves Money
• Improves Consistency and
Repeatability
• Corresponds well with traditional
purge methods
• Generates no waste water
• Improves Health and Safety - no
heavy equipment or noise; short
time in process or traffic areas.
www.SnapSampler.com 20