FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

Sampling 9. The line is now ready to be sampled. Open the sample canister valve and monitor sampling progress periodically. 10. When the sampling is complete close the valve and replace the brass cap on the canister;record final vacuum of canister(simply read built-in gauge) 11. Fill out canister sample tag(make sure the sample ID and date of collection recorded on the sample tag matches what is recorded on the COC exactly) 12. Return canisters in boxes provided(Unretumed canister replacement charge of $500 each) 13. Return sample media in packaging provided(Unreturned equipment charges: $45 per particulate filter;$50-500 per flow controller) 14. Fill out chain-of-custody and relinquish samples properly(it is important to note the canister serial numbers on the chain-of-custody) 15. Place chain-of-custody in box and retain pink copy 16. Ship accordingly to meet method holding times 5.3.3 Special Considerations for Soil Gas and Landfill Gas Sampling • Use inert tubing.Teflon®tubing is recommended.Tubing with an outer diameter of 1/4 in.works best with the fittings on the particulate filter. • Do not reuse tubing.$2 per foot for new tubing is a small price to pay for peace of mind. • Purge tubing adequately.A long length of tubing has significant volume of"dead air" inside. Without purging, this air will enter the canister and dilute the sample. Consider using a handheld PID/FID to confirm that you have purged the tubing and are drawing sample air through the tubing. • Avoid leaks in the sampling train. Leaks of ambient air through fittings between pieces of the sampling train (e.g., tubing to particulate filter)will dilute the sample. Always use compression fittings for all connections;never use tube in tube connections. • Don't sample water. If moisture is visible in the sample tubing,the soil gas sample may be compromised. Soil gas probes should be at an appropriate depth to avoid reaching the water table.Additionally, subsurface vapor should not be collected immediately after measurable precipitation. • Purge the sample port.A sample port on an SVE system or LPG collection system can accumulate solids or liquids depending upon the location of the port in the process and the orientation of the port.An influent sample port located upstream of a filter or moisture knock-out can be laden with particulates or saturated with water vapor. Heavy particulate matter can clog the particulate filter and foul the canister 25