Rainwater Runoff Field Instructions
1. Print enough Chain of Custody Forms so that the deployment and retrieval data for each Sentinel™ Passive Sampler can be recorded on a row corresponding to the sample. One copy of the Form is sufficient for 20 Sentinel™ Passive Samplers.
2. If the deployment plan includes a field blank, leave the field blank in the tube in which it was shipped, clearly mark the tube “Field Blank”. Do not deploy the field blank.
3. Make provisions to save the 50 mL tapered centrifuge tube and the resealable plastic packaging for reuse in shipment to the lab. (No need to match the Sentinel™ Passive Sampler to the 50 mL tube or other packaging materials in which it was shipped.)
4. Remove the Sentinel™ Passive Sampler from the 50 mL tapered centrifuge tube. It is shipped from the manufacturer with a metal tag attached to the flat end that can serve as a weight.
5. Position the Sentinel™ Passive Sampler where it will be immersed in storm water runoff for at least 15 minutes. If necessary, anchor the Sentinel™ Passive Sampler to keep it from being swept away
6. At deployment, record on the Chain of Custody Form:
- The sample ID number on the metal tag (or other system),
- The date deployed,
- The time deployed (to the nearest 15 minutes), and
- The water speed at the sample site (likely 0-2 cm/min).
7. A deployment of approximately 15 minutes duration will be sufficient to screen storm water runoff to a limit of detection of ~60 ng/L (ppt) for all PFAS analytes addressed in EPA Method 1633.
8. At retrieval, record on the row in the Chain of Custody Form corresponding to the Sentinel™ Passive Sampler:
- The date retrieved,
- The time retrieved (to the nearest 15 minutes), and
- The water temperature (in °C).
(The water temperature could be recorded at deployment.)
9. Replace the Sentinel™ Passive Sampler in a 50 mL tapered centrifuge tube and tighten the cap. Place the tube with Sentinel™ Passive Sampler in the resealable plastic bag or other return packaging.
10. Place all Sentinel™ Passive Samplers in refrigerated packaging and ship using at most two-day delivery to laboratory for analysis.