In addition to the requirements of subparts A and B of this part, a claimant must establish—
(a)
The nature of the specific public services provided and the need for those services;
(b)
That the services occurred during or after removal activities;
(c)
That the services were provided as a result of a discharge of oil and would not otherwise have been provided; and
(d)
The net cost for the services and the methods used to compute those costs.