Prepare and analyse the service station soil metals batch

You are a laboratory technician in Analytical Chemistry.

Simulated workplaceIntermediate missionCAQA Veritas Laboratories

What is going on

Coastal Environmental Consulting has submitted twelve soil samples from a former service station under job CJ-26-0421 for the metals suite, hydrocarbons and BTEX. The metals suite is analysed by inductively coupled plasma optical emission spectrometry after acid digestion. The last metals batch had a copper spike recovery of 68 percent and is under investigation, so Jasper Nguyen wants fresh calibration standards and a fresh spike solution prepared and recorded. Digestions are done at the digestion block under the fume cupboard with face shield and gauntlets after a recent acid splash. The client needs results by Thursday for a site assessment report.

Jasper Nguyen, Senior Laboratory Technician
Subject: Metals batch for the service station soils

The twelve soil samples from the former service station (job CJ-26-0421) need the metals suite by Thursday. Please prepare the digests under the fume cupboard following the method and the risk assessment, make up fresh calibration standards and a new spike solution because the last copper spike recovery failed, run the batch on the spectrometer with the full quality control set, and review the batch before you hand it to me. If anything is outside limits, raise it in the nonconformance register rather than rerunning quietly.

Your brief

Prepare the digests and standards safely and to the method, run the batch with the full quality control set, review the batch against the acceptance criteria, record any nonconformance and submit the batch for technical review with complete records.

Work through it

You do not need to do it all. Doing a few of these will show you what the work is like. Your ticks and notes stay on this device.

Read the method, the chemical risk assessment for acid digestion and the hazardous chemicals register entries for nitric and hydrochloric acid, and set up the fume cupboard with the required personal protective equipment.
Check the balance daily reference mass record and the spectrometer status in the equipment register before weighing any sample.
Weigh, digest and make up the twelve samples plus method blank, duplicate, laboratory control sample and matrix spike, recording every weight and volume on the worksheet.
Prepare fresh calibration standards and a fresh spike solution from certified stock, recording lot numbers, expiry dates and dilutions in the reagent log.
Run the batch on the spectrometer with calibration verification and check standards at the frequency the method requires, and save the raw data to the batch folder.
Review the batch: calibration criteria, blank, duplicate precision, control sample and spike recovery, and calculate results on a dry weight basis using the moisture results.
Record any quality control result outside limits in the nonconformance register with the samples affected, then update the sample register status to Awaiting review and hand the batch to Jasper Nguyen.

My notes: what did I enjoy, and what surprised me?

What someone in this role would produce

Completed digestion worksheet
Reagent and standard preparation record
Batch quality control summary with acceptance decisions
Nonconformance record if raised
Sample register status updates

Printing this is a record of what you explored. It is not a certificate or a qualification.