(1) When submitting a contingency plan to the department under RCW 88.46.060, any umbrella plan holder that enrolls both tank vessels and covered vessels that are not tank vessels must, in addition to satisfying the other requirements of this chapter, specify:

(a) The maximum worst case discharge volume from covered vessels that are not tank vessels to be covered by the umbrella plan holder's contingency plan; and

(b) The maximum worst case discharge volume from tank vessels to be covered by the umbrella plan holder's contingency plan.

(2) Any owner or operator of a covered vessel having a worst case discharge volume that exceeds the maximum volume covered by an approved umbrella plan holder may enroll with the umbrella plan holder if the owner or operator of the covered vessel maintains an agreement with another entity to provide supplemental equipment sufficient to meet the requirements of this chapter.

(3) The department must approve an umbrella plan holder that covers vessels having a worst case discharge volume that exceeds the maximum volume if:

(a) The department determines that the umbrella plan holder should be approved for a lower discharge volume;

(b) The vessel owner or operator provides documentation to the umbrella plan holder authorizing the umbrella plan holder to activate additional resources sufficient to meet the worst case discharge volume of the vessel; and

(c) The department has previously approved a plan that provides access to the same resources identified in (3)(b) [(b) of this subsection] to meet the requirements of this chapter for worst case discharge volumes equal to or greater than the worst case discharge volume of the vessel.

(4) The umbrella plan holder must describe in the plan how the activation of additional resources will be implemented and provide the department the ability to review and inspect any documentation that the umbrella plan holder relies on to enroll a vessel with a worst case discharge that exceeds the plan's maximum volume.