SMART: A Guided Tour - Part 4

A typical representation of fluorometer data.

Graphical Representation of Fluorometer Data

When collecting fluorometer data, the monitoring team first collects background data away from the oil slick. Then the team moves into the oil slick, collecting data under an untreated part of the slick. Due to natural dispersing of the oil, fluorometer readings are higher in the untreated area than in the area away from the oil slick. Finally, the team moves through the dispersant-treated part of the slick, where the dispersed oil results are highest.

The graph shown above is a typical representation of fluorometer data. The fluorometer readings are highest under the dispersed oil, indicating that dispersants are effective in dispersing the oil into the water column.

Here, a bottle is filled with water from the fluorometer for later lab analysis.

Assessing Dispersant Efficacy

Fluorometry is a powerful tool in assessing dispersant efficacy. It provides continuous collection of real-time data that can be relayed immediately to the Unified Command (UC). Fluorometry, however, is not as accurate as a full-scale laboratory analysis. Collecting water samples periodically during the monitoring operations provides verification of the fluorometry data, as well as important information for later use. Water samples are collected in brown bottles (to prevent photo degradation), are refrigerated in a cooler (to preserve sample integrity), then are sent for lab analysis.

A portable water laboratory that is used in Tier III monitoring.

Tier III: Expanded Monitoring

Tier III expands monitoring efforts by providing information about where the dispersed oil goes and what happens to it. Tier III provides the following level of monitoring:

• Two fluorometers are used on the same vessel to monitor dispersed oil at two water depths.

• Monitoring is conducted in the center of the treated slick at several water depths, from 1 to 10 meters.

• A portable water laboratory is used to provide data on water temperature, pH, conductivity, dissolved oxygen, and turbidity.

The additional monitoring provides useful data on the behavior and transport of the dispersed oil.