CPG Specimen Collection & Handling 4

Question 1

A soil sample for VOCs was preserved with methanol in the field. How must the sample be shipped?

Accepted Answer

In line with DOT hazardous materials rules for small quantities of flammable liquid

Answer

Methanol is a flammable liquid, so shipments must meet DOT/IATA rules, often under small- or excepted-quantity provisions.

Question 2

Which practice best prevents cross-contamination when sampling multiple monitoring wells with one non-dedicated pump?

Accepted Answer

Sampling from the least to the most contaminated well and decontaminating between wells

Answer

Going from clean to dirty wells and fully decontaminating between them lowers the risk of carrying contamination over.

Question 3

Oriented core is collected mainly to provide what information?

Accepted Answer

The true strike and dip of fractures, bedding, and other planar features

Answer

Orienting core against a reference line lets structural features be measured in their true in-situ orientation.

Question 4

What does a custody seal on a sample cooler do?

Accepted Answer

Shows whether the cooler was opened between sealing and receipt at the lab

Answer

A signed, dated custody seal over the lid reveals tampering because it must be broken to open the cooler.

Question 5

Which container type is generally right for groundwater samples analyzed for semivolatile organic compounds?

Accepted Answer

Amber glass bottle with a PTFE-lined cap

Answer

Amber glass protects photosensitive organics from light, and PTFE liners stop sorption to or leaching from the cap.

CPG - Certified Professional Geologist Practice Test