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Passive, No-Purge, Sampling

with the Snap Sampler

Know your sampleTrust your data

Mr. Sandy Britt, PG, CHG

ProHydro, Inc.Sandy.Britt@ProHydroInc.com

www.SnapSampler.com

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The Snap Sampler 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 triggercloses bottles in situ.

• No sample transfer requiredat the well head for VOCs-No exposure to air

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How the Snap Sampler works….

Insert

40ml 125ml

Push down to set Snap Cap

Insert

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How the Snap Sampler works…continued

Insert trigger

Attach fitting

Add safety cable tie

Trim excess Snap Cap

Lower downhole

• Modular samplers allow up to 4 bottles per trigger

• Multiple triggers can be used for multiple sampling depths

Hang on Dock Ring

Secure

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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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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

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You can Snap Sample by yourself…

…without this truck…

…and with almost none of this equipment

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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

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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

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• Very good correlations (R2=0.99+, 0.98)

• No exposure during pouring yields slightly higher concentrations

• CVOC constituentsBritt, Parker, Cherry, in Prep.

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• Very good correlation (R2 = 0.99+)

• No exposure during pouring yields slightly higher concentrations

• BTEX MTBE CVOC TN & Associates, US Navy, unpublished data

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• Very good correlation (R2 = 0.99+)

• Non volatile shows equivalent concentrations

• Perchlorate

Private site, unpublished data

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• Very good correlation (R2 = 0.99+) for ALL comparisons

• No exposure during pouring yields slightly higher concentrations

• VOCS, 1,4-dioxane, anionsParsons, 2005, McClellan Air Force Base, Sacramento, CA

40ml

125ml

R2 = 0.99 for all analyte comparisons to low flow

Little Scatter

Snap Sampler vs. Low Flow

Low Flow Purge Sample Concentration (g/L)

Sn

ap

Sam

ple

Co

nce

ntr

ati

on

(g

/L)

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Low Flow vs. 3 Volume Low Flow vs. PDB

3 Volume vs. PDB Low Flow vs. Snap Sampler

R2 = 0.76 for VOCs R2 = 0.79 for VOCs

R2 = 0.58 for VOCs R2 = 0.99 for VOCs

Little Scatter

Parsons, 2005, Demonstration of No-Purge Groundwater Sampling Devices, McClellan AFB, Sacramento, CA

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PDB vs Hydrasleeve 3 volume vs Hydrasleeve

Snap Sampler vs. PDB Snap Sampler vs. 3 volume

R2 = 0.38 for VOCs R2 = 0.50 for VOCs

R2 = 0.95 for VOCs R2 = 0.90 for VOCs

Less Scatter

Less Scatter

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“..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?

McClellan Conclusion Summary (Parsons)

17www.SnapSampler.com

See Data Trends Sooner…

Many variables for purge: actual concentration, pump deployment position variations, equipment calibration, pumping duration, stability criteria requirements, wind, temperature, site surface or ambient air contamination, bottle fill rate, pour technique, speed of bottle closure, transport, analytical variability.

Fewer variables for Snap: actual concentration, transport, analytical variability.

Discern your data trend…

• Reduce monitoring• Close sites sooner

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Cost Savings for No-PurgeSnap Sampling?

YES!

www.SnapSampler.com

NPV Comparison

10-yr cost$105,122

30-yr cost$196,349

10-yr cost$201,758

30-yr cost$401,660

$0$50,000

$100,000$150,000$200,000$250,000$300,000$350,000$400,000$450,000

1 4 7 10 13 16 19 22 25 28

Time (Years)

NPV

$ (A

fter

Tax

)

Snap Sampler Well PurgeNice early break-even

19www.SnapSampler.com

NPV Comparison

10-yr cost$105,122

30-yr cost$196,349

10-yr cost$201,758

30-yr cost$401,660

$0$50,000

$100,000$150,000$200,000$250,000$300,000$350,000$400,000$450,000

1 4 7 10 13 16 19 22 25 28

Time (Years)

NPV

$ (A

fter

Tax

)

Snap Sampler Well Purge

Dedicated Snap Sampler Equipment?

Snap Samplers are dedicated equipment that will be reused for years

The one-time expense is never repeated, so your after one event, savings is comparable to other passive approaches that have minimal dedicated equipment cost

Cost per well depends on may factors, but can be as low as $225 at standard prices, less with bulk purchases

Guarantee consistent, Guarantee consistent, longlong--term, high quality term, high quality data with a onedata with a one--time time expenditure.expenditure.

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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