(1) The deposit referred to in s. 630.021 shall be made under a written trust agreement between the insurer and the trustee, consistent with the provisions of this chapter; and the agreement and any amendments thereto shall be authenticated in such form and manner as the office may designate or approve.
(2) The agreement shall not be effective until filed with and approved in writing by the office. If the office finds that the trust agreement is sufficient in form and in conformity with law, that the trustee or trustees are eligible as such, and that the trust agreement is adequate to protect the interests of the beneficiaries of the trust, it shall give its written approval thereof. If the office finds that any of the above-mentioned requisites do not exist, it shall refuse to approve the trust agreement.
(3) If after a trust agreement has become effective the office finds that the requisites for approval of the agreement no longer exist, it may withdraw its approval.
(4) A trust agreement may be amended, but no amendment shall be effective unless the agreement as so amended is found by the office to be consistent with the provisions of this chapter and the amendment is approved by it.