On environmental issues, Mathias established a record as a strong advocate of the Chesapeake Bay. After touring the bay shoreline in 1973, he sponsored legislation that led to a study by the United States Environmental Protection Agency (EPA) two years later, which was one of the first reports that made the public aware of harmful levels of nutrients and toxins in the waters. As a result, the report was one of the catalysts for cleanup efforts, and evolved into the Chesapeake Bay Program. In recognition, the Charles Mathias Laboratory, part of the Smithsonian Institution, was established in 1988 as a research facility to analyze human impact on the bay. In 1990, the Mathias Medal was established by Maryland Sea Grant at the University of Maryland Center for Environmental Science as further acknowledgment of Mathias' environmental record. In 2003, thirty years after he launched a study of the Chesapeake, Mathias was recognized by the Army Corps of Engineers for the influential role he played initiating restoration efforts. From 1987 to 1993, Mathias was a partner at the law firm of Jones, Day, Reavis and Pogue. In 1991, Mathias was chosen by the U.S. Federal Reserve Board to lead a committee to supervise the operations of First American Bankshares, Inc. Prior to his arrival, First American had been secretly acquired by Bank of Credit and Commerce International, which resulted in a major banking scandal. Mathias was appointed chairman of the board of First American in November 1992, replacing former U.S. Attorney General Nicholas Katzenbach. He continued as chairman of First American until 1999. After his retirement, Mathias served on numerous boards and committees. He was a member of the Governor's Commission on State Taxes and Tax Structure (1989–1990), a member of the Maryland Civil War Heritage Commission (1992–1995), a member of the Kaiser Commission on Medicaid and the Uninsured, co-chair of the Task Force on the Presidential Appointment and Senate Confirmation Process (1996), a member of the board of the George C. Marshall International Center, a member of the board of OpenSecrets, a member of the board of WorldSpace Satellite Radio, and board member emeritus of Brown University's Watson Institute for International Studies. Additionally, Mathias served on the Board of Trustees of Enterprise Foundation (now Enterprise Community Partners) from 1980 through 2001. As of 2008, Mathias practiced law in Washington, D.C., and was a resident of Chevy Chase, Maryland. On October 28,