LONGEST CAVE DIVE IN CENTRAL BRAZIL

LONGEST CAVE DIVE IN CENTRAL BRAZIL

In September 20, 2004, Brazilian cave diver Gilberto Menezes accomplished a
solo penetration of 6,400 meters (21,000 ft) in the upstream sump of
Bananeira cave, state of Bahia in Central Brazil. The dive lasted 11 hours
23 minutes and was stopped in going passage. The Bananeira sump starts 400 m
inside the cave and comprises a narrow passage 3 m wide and 2 m high in
average with silty floor. Although the water is warm (c. 25ºC) visibility is
never more than 3 m being only 1.5 m during the 2004 dives. The underwater
passage is generally shallow in the first 3,500 m (25 m maximum depth)
becoming gradually deeper until a short loop at around 6,000 m penetration
brings the depth to 50 m. The dive was stopped in the ascending portion of
the loop at 20 m depth. In his longest push two Submerge Inc. UV-42 scooters
(specially adapted with 65-amph @ 24-volts NiMH batteries enabling a total
range of about 10,000 m per scooter!) were used. The dive used conventional
(open circuit) apparatus and a total of 33 tanks were either used or were in
place at the sump during the longest dive. Trimix 25/50 was used from the
surface to 25 m depth (up to 5,800 m penetration), Trimix 16/70 was used
from 25 to 50 m in depth (from 5,800 m to 6,400 m penetration). Nitrox 70
was used for decompression from 12 m to 7 m in depth (3,000 m to 1,800 m
penetration) and pure oxygen was used at 6 m depth (1,800 m penetration) and
3 m depth (1,500 m penetration).

Gilberto Menezes is the Brazilian most active cave diving explorer, having
now logged 35 solo dives over 150 m in depth at 4 Brazilian sites, including
a 274 m (898 ft) deep dive at the gigantic bell-shaped pit of Lago Azul and
a 220 m deep dive at Lagoa Misteriosa. The Bananeira cave project started
two years ago and up to now Gilberto Menezes has logged 43 dives in the sump
totaling over 170 hours of diving time. Diving is restricted to a few months
during the dry season. The water in the Bananeira sump comes from
neighboring Padre cave and it is estimated that at least 1.5 - 2 km of sump
remains to be explored until a connection is made. The project will be
resumed in 2005.

Gilberto Menezes would like to thank Rodney Nairne of Submerge Inc. for
supporting the project and making available the extra long-range scooters.
Tom Mount and Jim Lockwood provided training and information on DPV diving
and Dr. Bill Hamilton helped with decompression tables. Thanks is extended
to Augusto Auler for pointing the potential of the site and to local farmer
Nogueira for helping with field work logistics. IBAMA-CECAV provided diving
permits.