EAM.10:5 - Archetypal Grounding

A shared operation changes the comparison

Consider a separate constructed service requirement. Two interventions P and Q together and a different complete solution Z are both qualified to supply it over the same horizon. P or Q alone is insufficient. Their subsequent operating, ending and other material consequences are equal; all different costs are payable now in €million, and funding is sufficient for either whole solution. Thus their initial cost difference decides this bounded comparison.

P costs 2.0, including 0.2 mobilization, and Q also costs 2.0 including 0.2. Z costs 3.9. The operating practitioner establishes that P and Q can be performed sequentially during one qualified visit, using one 0.2 mobilization. Required service remains supported during the work; the shared visit incurs no additional consequence outside the supplied account.

The whole P+Q account is 1.8 + 1.8 + 0.2 = 3.8. Adding the separate estimates would prefer Z at 3.9; the supported joint account prefers P+Q by 0.1. That result concerns one actual payment saved through a feasible work arrangement.

Suppose incompatible access windows require two visits and two mobilizations. P+Q returns to 4.0 and Z becomes cheaper at 3.9. If instead the proposed shared visit fails the service condition, remove that arrangement as ineligible and compare any qualified two-visit arrangement with Z. Reducing its price cannot repair the lost service. EAM.11 establishes which visit arrangement is feasible; EAM.10 uses its consequences.

The example does not infer a common saving for CityWater’s separate station jobs. A proposed CityWater sharing arrangement would need its own work, service and financial account before altering the following result.

The sixteen supplied CityWater combinations

The common CityWater application supplies four two-option choices. Initial capital must not exceed €8 million, initial operating expenditure €0.60 million, annual operation €3 million and the available team/outage time twelve days. All amounts and eligibility results are constructed.

FFMK—refurbish A and B, modify C, continue D—uses €7 million capital, €0.50 million initially for operation, €1.85 million annually and eight days. Its present cost is €14.592284 million, the lowest among the declared eligible combinations. The common application provides all sixteen rows, so this conclusion is reproducible.

Adding D replacement while retaining the other choices gives FFMR: €10 million capital and lower present cost of €13.080344 million. It is infeasible at the €8 million allocation. Switching C to leased service permits D replacement within capital, but FFLR costs €15.350138 million overall.

If the funding board raises capital to €10 million, FFMR becomes preferred. If D continuation instead loses its engineering qualification, FFLR becomes preferred at the original limits. These changed outcomes follow from changed conditions, not from changing the ranking arbitrarily.