Structure and Approach of the UTM

Structure and Approach of

the UTM

This chapter describes the tiered testing approach used in the UTM. This

approach is very similar in concept to the tiered structure of the OTM and ITM,

both of which were designed to provide information needed to determine the

potential for contaminant-related impacts of proposed discharges without

necessitating unnecessary testing evaluations. The conceptual similarity between

the steps in each tier of the UTM evaluation process, the risk assessment process,

and fundamentals of testing and evaluations common to multiple pathways are

also described.

2.1 Tiered Structure for Evaluations and Testing

The UTM uses a four-tiered evaluation process for each of the five pathways.

This tiered approach should be initiated at Tier I for each pathway and is designed

to aid in generating appropriate and sufficient, but not more than necessary,

information to make decisions regarding the need for management actions. This

allows optimal use of resources by focusing the least evaluative effort on projects

where the potential need (or lack thereof) for management actions is clear, and

expending the most effort on operations requiring more extensive investigation to

determine the need for management actions.

To achieve this objective, the evaluative guidance for each of the five

pathways is arranged in a series of tiers, or levels of intensity of investigation. At

the outset of a typical evaluation of a particular pathway, it may be possible

conduct evaluations in general terms. Evaluation at successive tiers involves more

extensive and specific information about the potential need for management

actions. Successive tiers may involve more time-consuming and expensive

procedures but provide more extensive information allowing more detailed

evaluations of the need for management actions. The progressive increase in

information from successive tiers means that a project is carried through the tiered

evaluation structure until the information necessary and sufficient for a decision is

obtained, and no further.

It is not true that increased information obtained from evaluation in

progressively higher tiers always results in greater confidence in the decision. As a

simple illustration, if dredged material clearly meets the criteria indicating

2-1

Chapter 2 Structure and Approach of the UTM