ABSTRACT
Selection and design of systems and technologies for treatment of mixed low-level waste (MLLW) requires knowledge and understanding of the expected costs, schedules, risks, performance, and reliability of the total engineered system. These factors are all related. For example, cost is a function of:
Schedule. The longer the schedule required to treat a given quantity of waste, the greater the operating and maintenance cost.
Reliability. The greater the system reliability, the lower the maintenance cost, the greater the system availability, and therefore the shorter the schedule. However, increased reliability may increase capital cost for more reliable equipment. A system with low reliability will increase operational and economic risk associated with increased probability of equipment failure, increased maintenance and a drawn-out schedule.
Risk. Additional costs are required to mitigate environmental safety and health (ES&H) risks associated with handling and treating mixed waste. The design requirements for risk mitigation will depend on the waste content and the technologies used in the treatment process.
Performance. A system that performs poorly in terms of meeting treatment goals and regulatory requirements may require post-treatment, re-treatment, or system modifications, all of which will increase cost and schedule.
The purpose of this section is to provide the reader with insight into factors involved in determining the cost of a mixed waste treatment system, the relative cost of various treatment concepts, and the tradeoffs that should be considered when developing an economic system design.
