280-20-70 R.I. Code R. § 33.8
In those cases where the taxpayer is unable to furnish the evidence required and outlined to support a claim for exemption at the time he or she purchases items of tangible personalty or supplies; he or she should pay the tax and, thereafter, when able to properly support the claim for exemption, he or she should file an appropriate claim for refund. Such claims must indicate the items purchased, the date purchased and from whom purchased, the date installed, a statement that such items are and will continue to be used in on-site hazardous waste recycling, reuse or treatment, satisfactory evidence that the Rhode Island sales and use tax on such items has been paid, the date of such payment and to whom paid and certification by the Department of Environmental Management as indicated in § 33.6 of this Part.
280 R.I. Code R. § 280-RICR-20-70-33.8