When a settlement is proposed in any proceeding brought under this act, notice of the proposed settlement shall be sent to all known responsible persons and published in the Pennsylvania Bulletin and in a newspaper of general circulation in the area of the release. The notice shall include the terms of the settlement and the manner of submitting written comments during a 60-day public comment period. The settlement shall become final upon the filing of the department's response to the significant written comments. The notice, the written comments and the department's response shall constitute the written record upon which the settlement will be reviewed. A person adversely affected by the settlement may file an appeal to the board. The settlement shall be upheld unless it is found to be arbitrary and capricious on the basis of the administrative record.