231
• Economical aspect, consistency and equal
value of environmental goods over the time :
this last point assumes that people will consider the value of “ res natura ” without any
fl uctuation both economic and social over the
time (the value of gas or oil, for instance, will
probably change from now to few decades).
It’s also important to clearly focus the engineering efforts on the very fi rst phases of the
“avoid, reduce, mitigate” design of a project. The
stress must be maintained on these two fi rst
phases, because the best compensatory mitigation to offset residual impact is the one that we do
not need to do. For offshore windmill, the position of the project, the technical construction
choices, the planning, and of course the design of
the foundations clearly need to be more effective
to ensure their better integration in coastal ecosystem (see below Fig. 5 , from Lacroix and Pioch
2011 ).
Table 2 (continued)
Services gains at the injury area
Year
Intermediary services gains (%)
Intermediary
services gains
average (SSA)
Discount factor
Discounted intermediary
services gained average
(SSA)
Beginning
End
Average
2019
60.00 %
70.00 %
65.00 %
6500.000
0.855
5556.227
2020
70.00 %
80.00 %
75.00 %
7500.000
0.822
6164.453
2021
80.00 %
85.00 %
82.50 %
8250.000
0.790
6520.095
2022
85.00 %
90.00 %
87.50 %
8750.000
0.760
6649.281
2023
90.00 %
95.00 %
92.50 %
9250.000
0.731
6758.884
2024
95.00 %
100.00 %
97.50 %
9750.000
0.703
6850.221
2025
100.00 %
100.00 %
100.00 %
10000.000
0.676
6755.642
2026
100.00 %
100.00 %
100.00 %
10000.000
0.650
6495.809
2027
100.00 %
100.00 %
100.00 %
10000.000
0.625
6245.970
2028
100.00 %
100.00 %
100.00 %
10000.000
0.601
6005.741
2029
100.00 %
100.00 %
100.00 %
10000.000
0.577
5774.751
2030
100.00 %
100.00 %
100.00 %
10000.000
0.555
5552.645
2031
100.00 %
100.00 %
100.00 %
10000.000
0.534
5339.082
2032
100.00 %
100.00 %
100.00 %
10000.000
0.513
5133.732
2033
100.00 %
100.00 %
100.00 %
10000.000
0.494
4936.281
2034
100.00 %
100.00 %
100.00 %
10000.000
0.475
4746.424
2035
100.00 %
100.00 %
100.00 %
10000.000
0.456
4563.869
2036
100.00 %
100.00 %
100.00 %
10000.000
0.439
4388.336
2037
100.00 %
100.00 %
100.00 %
10000.000
0.422
4219.554
2038
100.00 %
100.00 %
100.00 %
10000.000
0.406
4057.263
2039
100.00 %
100.00 %
100.00 %
10000.000
0.390
3901.215
2040
100.00 %
100.00 %
100.00 %
10000.000
0.375
3751.168
2041
100.00 %
100.00 %
100.00 %
10000.000
0.361
3606.892
2042
100.00 %
100.00 %
100.00 %
10000.000
0.347
3468.166
2043
100.00 %
100.00 %
100.00 %
10000.000
0.333
3334.775
2044
100.00 %
100.00 %
100.00 %
10000.000
0.321
3206.514
2045
100.00 %
100.00 %
100.00 %
10000.000
0.308
3083.187
Beyond
77079.667
Total discounted service unit years gained average (SSAs):
226561.213
Discounted services average gained per surface unity (SSAs):
22.656
Compensatory mitigation habitat size (sq. m): 2.000 × 260000/22.656
22951.855
How to Size “Fair” Compensatory Mitigation Due to Coastal Area Destruction…