It doesn't help you now, but unfortunately it's all there on their website & explains the bill you got, how they justify it though I'll never know.
You would have thought that a combined fixed price per tonne per day for landing and parking would be a reasonable.
Landing charges (inclusive of navigation service charges).
Fixed Wing
Landing Charges are calculated on MTOW /Maximum Take-Off Weight:
First 5 Tonnes (per Tonne) €25.00
Next 5-10 Tonnes (per Tonne) €23.00
Next 10-20 Tonnes (per Tonne) €22.00
Over 20 Tonnes (per Tonne) €20.00
Parking of Aircraft
The first three hours after touchdown are free.
The following rates are applicable after touchdowns allocation has expired:
Per Hour Parking
(07:00 – 22:00)
Parking per aircraft (up to 4.9 Tonne) €4
Parking per aircraft (5 to 7.9 Tonne) €10
Parking per aircraft (over 12 tonne) €12
Overnight Parking(22:00 – 07:00)
Parking per aircraft (up to 4.9 Tonne) €24
Parking per aircraft (5 to 7.9 Tonne) €48
Parking per aircraft (over 12 tonne) €75
You didn't take your private B747 did you?