W. Va. Code § 22-17-10

The director shall promulgate rules, as provided in section six of this article, containing requirements for maintaining evidence of financial responsibility as deemed necessary and desirable for taking reasonable corrective action and for compensating third parties for bodily injury and property damage caused by sudden and nonsudden accidental releases arising from operating an underground storage tank. Such means of financial responsibility may include, but not be limited to, insurance, guarantee, surety bond, letter of credit, proof of assets or qualification as a self-insurer. In promulgating rules under this section, the director is authorized to specify policy or other contractual terms, conditions or defenses which are necessary or are unacceptable in establishing such evidence of financial responsibility in order to effectuate the purposes of this article.