To date there have been charcoal-making pits uncovered on Galiano, Mayne, Pender, Prevost, Salt Spring and Saturna Islands. The Tasaka charcoal pits were rediscovered in Mouat Park in 2013 and one has been restored for viewing. Two pits were operated in this location.

The pits are really pear-shaped ovens or kilns approximately 16' long, 14' wide and 5.5' deep dug into the ground and lined with stone. At the narrower end of the pit is a fireplace with a chimney.

Approximately six logs the same length as the pit are laid on the bottom with branches between to allow air to flow. Across this base of logs is laid another row of smaller logs on top of which are piled around two or three cords of logs standing on end. The logs are covered with branches and the entire structure is covered with sand and clay sealing the wood into a dome-shaped kiln. A fire is started at the narrow end until the wood begins to smoulder. The secret is to restrict the amount of air so the wood doesn't burn up and not to allow it so smoulder too hot so the charcoal doesn't break down. A large tub of water is always kept on hand to cool down the oven if necessary. The pit must be tended at all times for the three to five day process. When the smoke turns a translucent purple the charcoal is ready.

The pits were often built on land that needed to be cleared. The trees chopped down in clearing provided the wood for making charcoal. Tye [Tasaka] recalls that birch was the best wood as it yielded most charcoal although poplar was also good. Fir burned the hottest and was used for fuel but care had to be taken not to use too much to avoid a bonfire that would burn up the wood rather than produce charcoal. On a CBC Radio interview, Tye said the charcoal was exactly the same as is still made and used in Japan and is similar to North American charcoal except here it is compressed into briquettes. In Japan, natural charcoal is preferred.

Recent research suggests that the charcoal pits on Galiano Island were modelled after the pits used in the Wakayama Prefecture in Japan. The design and construction of these charcoal pits date back thousands of years.

Tye remembers helping his father load around 200 sacks of charcoal onto his fishing boat for delivery to Victoria. Masue [Tasaka] recalls her job was to keep water in the bucket that was always on hand to cool the pit if it should get too hot. Another of her responsibilities was to sew the bags closed after being filled with charcoal. Tye was in charge of the pit operation and had to report each day to his father on progress and any problems encountered. It would take a month to make a boatload and they would make two or three trips each winter. Charcoal sold for $0.30 a sack so each trip generated around $60. In Victoria, the charcoal was used to heat the oil used in the manufacture of soap. Charcoal was used because it provided smokeless, stable heating. It was also used to make an explosive called stumping powder that was used to blast tree stumps out of the ground. The charcoal from Mayne Island was apparently shipped to the canneries on the Fraser River where it heated the solder used to seal the canned fish cans. Some local island residents also used charcoal to heat their homes unaware of the risk of carbon monoxide poisoning.

Ironically, during World War II when the Japanese had been interned, Canadian soldiers used the pits in target practice. Some soldiers would climb into the pits and hold up targets that the other soldiers would shoot at with their rifles.