What are my risks?
Eruptions on Kauai
The
main mass of Kauai is about 3 to 5 million year old, although
there were a few very small eruptions on the island as late
as about 400,000 years ago! After a long period of no eruptions
(maybe something like 1/2 to 1 and 1/2 million years, the latest
stage of volcanism occurred on Kauai, the post-erosional, or
rejuvenated stage. On Kauai, the lavas and other volcanic material
from this stage have been called the Koloa Volcanics.
Vog and Laze Hazards for Kauai
County
Although
the Koloa, Makaweli, and Napali volcanoes are probably dead,
volcanic hazards do affect the island. Volcanoes spew noxious
plumes of acidic gases. The resulting vog and laze effect many
communities across Kauai County.
When
a volcanic erupts, sulfur dioxide within the molten rock is
converted to sulfuric acid. The resulting plume is known as
vog (volcanic fog). Gases are also produced at the ocean. When
the lava enters the ocean, hydochloric acid is produced - called
laze (lava haze). Both of these gases can contain particulate
matter, such as volcanic glass or trace metals.
Vog
and laze are carried by winds across the county. The impacts
include:
- obscured views;
- lower agricultural
yields for certain crops;
- adverse health
effects for people with respiratory or heart conditions;
and
- acidified rainwater
catchment tanks (which, in turn, produces a secondary hazard
of leached lead in local water supplies).