long ramps in June 1971. Jacqueline Kennedy Onassis was buried at the site alongside Kennedy following her death in May 1994. Senator Edward M. Kennedy was buried about south of Robert Kennedy's memorial between two maple trees shortly after his death on August 25, 2009, from brain cancer. The Arlington Oak The 220-year-old "Arlington Oak", which stood off-center within the Kennedy memorial gravesite area was uprooted and killed on August 27, 2011, during Hurricane Irene. The gravesite was closed to the public for two days to remove the tree and stump, but reopened on August 30. On Arbor Day, April 27, 2012, a sapling grown from an acorn of the Arlington Oak was planted at the same site. Two other Arlington Oak saplings were planted nearby, while a fourth was planted in Section 26 near Tanner Amphitheater and a fifth in Section 36 near Custis Walk. Maintenance Arlington National Cemetery experts said in 2001 that it cost about $200 a month to keep the flame burning. Its original, custom-manufactured ignition system, contained in a box buried a few feet from the grave, controlled the flow of gas and oxygen to the flame and activated a 20,000-volt spark ignition electrode near the gas burner whenever the flame was extinguished. In 2012, the automatic ignition system began clicking audibly. In early 2013, a $350,000 contract was awarded for upgrading the system. During the work the permanent flame was extinguished after being transferred to a temporary flame to one side. The refurbishment replaced the original burner with one not requiring a separate oxygen supply, laid new gas lines, relocated gas pressure regulators, added controls to improve energy efficiency, and replaced electrical lines. The flame was returned to the upgraded permanent eternal flame on May 17, 2013, and the temporary flame extinguished. In 2010, the carved inscriptions in the low stone wall in front of the site were renewed, which power cleaning and weather had made difficult to read. The Knights of Columbus donated $6,000 to have the letters darkened and more deeply incised in time for the 50th anniversary of Kennedy's inauguration. Gordon Ponsford, a sculptor who restored several major monuments at Arlington National Cemetery, performed the work. On December 10, 1963, a group of Catholic schoolchildren accidentally extinguished the temporary flame while sprinkling it with holy water. A cemetery official quickly relit the flame by hand. In August 1967, an exceptionally heavy