How can you collect and handle soil samples for geochemical analysis?

1 Planning your sampling program

Before you start collecting soil samples, you need to define your objectives, scope, and budget for your geochemical survey. You also need to research the geology, topography, vegetation, climate, and land use of your target area, as well as the existing data and maps available. Based on this information, you can design your sampling strategy, including the sampling density, pattern, depth, and method. You should also select the appropriate analytical techniques and quality control measures for your project.

2 Executing your sampling program

When you are ready to collect soil samples, you need to follow some best practices to ensure consistency and accuracy. You should use clean and durable tools and containers, such as plastic scoops, buckets, and bags, and avoid metal or wood that can contaminate your samples. You should also wear gloves and avoid touching the samples with your hands. You should follow the sampling protocol that you established in your planning stage, and record the location, date, time, depth, and other relevant information for each sample. You should also collect duplicate, blank, and reference samples for quality assurance.

3 Documenting your sampling program

Documentation is a crucial part of your soil sampling program, as it provides the evidence and context for your geochemical data. You should keep a detailed field logbook, where you record all the information about your sampling program, such as the objectives, methods, procedures, equipment, personnel, and observations. You should also label each sample clearly and accurately, using a unique identification code and a waterproof marker. You should also create a sample list, where you summarize the key information about each sample, such as the code, location, depth, weight, and analysis requested.

4 Preparing your samples for analysis

Before you send your samples to the laboratory for geochemical analysis, you need to prepare them properly to avoid degradation or contamination. You should first air-dry your samples in a clean and well-ventilated area, away from direct sunlight or heat sources. You should then sieve your samples to remove coarse particles and organic matter, and homogenize them by mixing them thoroughly. You should then weigh your samples and split them into aliquots for different analyses. You should also label each aliquot with the sample code and the analysis required.

5 Storing your samples for analysis

Storing your samples correctly is important to preserve their integrity and quality until they are analyzed. You should store your samples in sealed and labeled plastic bags or containers, and avoid exposure to moisture, heat, light, or dust. You should also store your samples in a secure and organized location, such as a locked cabinet or a designated room. You should keep an inventory of your samples and update it regularly. You should also retain some samples for backup or future use, in case of loss or damage.

6 Transporting your samples for analysis

Transporting your samples to the laboratory for geochemical analysis is the final step of your soil sampling program, and it requires careful planning and coordination. You should pack your samples in sturdy and waterproof boxes or bags, and protect them from shocks and vibrations. You should also attach a copy of your sample list and a chain of custody form to each package, and seal them with tamper-evident tape. You should then choose a reliable and reputable courier service, and track your shipment until it reaches the laboratory. You should also communicate with the laboratory staff and confirm the receipt and condition of your samples.