Ill. Admin. Code tit. 35 § 811.707
An owner or operator may satisfy the requirements of this Subpart by establishing more than one financial mechanism per site. These mechanisms are limited to trust funds, surety bonds guaranteeing payment, letters of credit and insurance. The mechanisms must be as specified in 35 Ill. Adm. Code 811.710, 811.711 and 811.713 through 811.720, as applicable, except that it is the combination of mechanisms, rather than the single mechanism, that must provide financial assurance for an aggregate amount at least equal to the current cost estimate for closure, post-closure care or corrective action, except that mechanisms guaranteeing performance, rather than payment, may not be combined with other instruments. The owner or operator may use any or all of the mechanisms to provide for closure and postclosure care of the site or corrective action.
Ill. Admin. Code tit. 35, § 811.707
Amended at 23 Ill. Reg. 2794, effective February 17, 1999