Sydney Wynne "Syd" Porter Jr., a noted physicist and radiation expert who was called to Three Mile Island, Pa., in 1979 after an accident destroyed a reactor in what proved to be the nation's worst nuclear incident, died April 23 of lymphoma at a Haverford, Pa., nursing home.
Mr. Porter, who had homes in St. Michaels and Ardmore, Pa., was 78.
The son of a Baltimore Sun advertising department solicitor and a noted bibliophile, he was born in Baltimore and raised on Maywood Avenue in Mount Washington. He was a 1950 graduate of St. Paul's School.
He was a 1954 graduate of St. John's College in Annapolis and did extensive postgraduate work in physical chemistry at the Johns Hopkins University and in the field of radiochemistry at New York University.
From 1957 to 1963, Mr. Porter was coordinator of health physics at General Dynamics Corp.'s Electric Boat Co. in Groton, Conn., where his duties included developing radiation safety programs for the Navy's early nuclear submarines, including the USS Nautilus.
Mr. Porter became head in 1963 of the radiological safety department at the Armed Forces Radiology Research Institute at the National Naval Center in Bethesda.
He served as a member of the U.S. Department of Defense Reactor Inspector General's Team and was awarded the department's Antarctica Service Medal for his work at the U.S. Antarctic research center at McMurdo Station in Antarctica.
From 1969 to 1974, he was vice president of Health Physics Operations and a co-founder of Radiation Management Corp. in Philadelphia.
In 1974, he established Porter Consultants Inc., also in Philadelphia, which provided radiation safety and health physics consulting to the nuclear industry.
"Early on the morning of March 28, 1979, he was one of the first outside radiation experts called to respond to the nuclear accident at Three Mile Island nuclear generating station near Harrisburg, Pa.," said John Eringis, his son-in-law, who lives in Gladwyne, Pa.
The loss of coolant at the power plant, which lasted for only 30 minutes, resulted in a 50 percent meltdown and destruction of the core of the No. 2 reactor in the facility located along the Susquehanna River near Middletown, Pa.
The reactor, officially known as TMI-2, was permanently shut down.
"During the weeks and months following the incident, he and his team assisted the reactor's station staff with assessments of radioactive materials released during and after the accident, and radiologic dose assessments of plant workers and the public," said Mr. Eringis.
"He testified before Congress about the accident response. His company was responsible for Three Mile Island's radiological environmental monitoring program from 1979 to 1982," he said.
Mr. Porter continued working at his company until retiring in 2009 because of failing health.
In addition, Mr. Porter had been an adjunct professor at Drexel University in the Graduate School of Environmental Studies.
"He was also a well-known educator of other health physicists and workers responsible for radiation safety throughout the country," his son-in-law said.
He was a fellow of the Health Physics Society and during 1991-1992 was president of the American Association of Radon Scientists and Technologists.
Mr. Porter was a charter member and an early president of the Baltimore-Washington Chapter of the Health Physics Society, and was a past president of the Delaware Valley Chapter for Radiation Safety, which presented him with its Meritorious Service Award last year.
He was also a diplomate of the American Academy of Health Physics, and a member of the American Nuclear Society and the American Association of Physicists in Medicine.
A lifelong science enthusiast, Mr. Porter helped research and restore a piezo-electric device, which was a precursor to the dosimeter, a radiation detector, that Pierre Curie made for his wife, Madame Marie Curie, who donated the instrument in 1921 to the Mutter Museum of the College of Physicians in Philadelphia.
Mr. Porter traveled to Bethlehem, Pa., each May to attend the annual Bethlehem Bach Festival and to hear the Bach Choir of Bethlehem perform Bach's Mass in B minor.
He also served for many years as a member of the board of the Bach Choir of Bethlehem. He had studied at the Barnes Institute in the Philadelphia suburb of Lower Merion Township.
Mr. Porter, who was an avid Chesapeake Bay sailor, maintained an interest in maritime art and history. His philanthropic interests also included the Independence Seaport Museum in Philadelphia and Mystic Seaport in Mystic, Conn.
"He had a catboat, motorboat and enjoyed kayaking in the bay," Mr. Eringis said.
Mr. Porter was a communicant of St. Michaels Episcopal Church, 301 S. Talbot St., St. Michaels, where a memorial service will be held at 10:30 a.m. June 11.
Also surviving is his daughter, Dawn Porter Eringis of Gladwyne, Pa.; two brothers, Geoffrey A. Porter of Rising Sun and Temple G. Porter of Raleigh, N.C.; a sister, Marguerite P. "Marti" Porter of Tiburon, Calif.; two grandchildren; and his longtime companion, Barbara Opper of Chevy Chase. His marriage to the former Lynn Kony ended in divorce.