Good Samaritan Clean Watershed Act

Good Samaritan Clean Watershed Act - Authorizes the Administrator of the Environmental Protection Agency (EPA) or a state or Indian tribe with an approved remediation program to issue a permit to a Good Samaritan to remediate inactive or abandoned mines. Defines "Good Samaritan" as a person that: (1) did not cause the historic mine residue at the inactive or abandoned mines; (2) is not liable or responsible under federal, state, or tribal law for remediation of such residue; and (3) does not have an ownership interest in such site during or since the creation of the residue.

States that to be eligible for a remediation permit, projects: (1) shall have the purpose of mitigating the effects of historic mine residue to improve the environment; and (2) are not in mines that are included on the National Priorities List of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) or mines that are subject to enforcement or response actions.

Provides conditions for permit issuance, including environmental improvement and financial resources requirements and consideration of objections by land management agencies and public trustees.

Deems permit activities to be compliant with the Federal Water Pollution Control Act (Clean Water Act or CWA) and CERCLA. Precludes the imposition of costs or damages under CWA and CERCLA related to the permit activities, except where the permittee's actions exacerbate the pollution as a result of gross negligence or intentional misconduct.

Provides for the transfer, modification, or termination of permits and the role of the permitting authority.

Requires the permitting authority to provide notice of the application for remediation of a mine site to: (1) designated lead state or tribal agencies; (2) local governments within a 20-mile radius of the project site; (3) federal, state, and tribal agencies that may have an interest in the application; and (4) the public.

Authorizes the Administrator to enforce this Act and prescribes civil monetary penalties.