System longevity, assessing the system's ability to ensure it can meet future needs and how long it takes before maintenance is necessary and the frequency of maintenance.
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Space requirements, assessing the system's ability to fit within the allotted space on the project site considering setback requirements.
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Maintenance costs, assessing the cost of system maintenance, including cleaning cycles and technology requirements based on frequency.
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Total cost of implementation, how much building the design will cost in total to install.
1 - Least Optimum (Worst) A score of one is the least optimum score, it represents the most expensive design, the layout and spacing requirements are not being met, and the maintenance frequency is most often. The maintenance costs for a score of one are outside the range of constructability for the project site and are more than $20,000. Installation costs for a score of one are more than $30,000. 2 - Worse A score of two represents being worse than the score of three but better than a one and its criteria ranges fall between scores one and three. 3 - Neutral A score of three represents the middle of scoring, the annual maintenance costs for a score of three fall within the more than $800 less than $1500 range. Installation costs for a score of three fall within the more than $10,000 less than $20,000 range. The system longevity for a score of three falls within the more than 10 years range. Spacing requirements for a three require needing some space on the project site to meet setback requirements once properly configured (ex. the septic system receives a score of three as it requires instillation of a leach field that is at minimum 50 feet away from the intermittent stream channel per ADEQ standards). 4 – Better A score of four represents being better than the score of three, but worse than a score of five, this score’s criteria ranges fall between the values for scores three and five. 5 - Optimum A score of five is the most optimum score, it represents the most cost effective and cheap design, that fits within the space, and the maintenance frequency is least often. The annual maintenance costs for a score of five are within the less than $800 range. The installation costs for a score of five are less than $10,000. The system longevity for a five is within the more than twenty years range. Spacing requirements for a score of five represent not needing a lot of space on the project site to meet setback requirements (ex. the sand filter receives a score of five for spacing requirements as it does not require the installation of a leach field).
