Sediment Sampling

What is Sediment Sampling?

Sediment sampling is the collection of marine, brackish or freshwater sediments from the seabed with either commercial divers or a grab device, like the PONAR Grab, so that it can be analyzed by a certified lab. Normally metals, PAHs and PCBs are tested, as well as grain size, moisture and pH.

When do you need sediment sampling?

Normally sediment sampling is a required on dredging or excavation projects in the marine environment. In order to dispose of the materials, they must be tested in accordance with tolerance thresholds for various chemicals as determined by provincial and federal regulations. For example, materials being disposed of at sea require a Disposal at Sea permit from Environment Canada.

What is typically involved?

Sampling requires that a person with sampling experience (i.e. Balanced Environmental) is hired by the proponent. For ocean disposal, the professional creates a sampling plan and submits it to Environment Canada for approval. Once approved, the professional gives Environment Canada 3 weeks notice of a proposed sampling date. Samples are collected normally with a PONAR grab and data is recorded. Samples are submitted to a certified lab for analysis and the professional creates a sampling report for the proponent.

How long does the survey take?

Normally it takes at least 3 weeks for Environment Canada to respond to the sampling plan and an additional 3 weeks before they can be onsite. Further, it takes at least 2 weeks for the lab results to be processed by the lab and a week for the consultant to prepare the necessary documents. Therefore, the minimum turn around time is 9 weeks.

What Kind of report do I get?

At the end of the sampling you get a sediment sampling report which contains the lab results and compares the results to the thresholds correspond to the method of disposal. These reports range from 20 to 100 pages.