Simplify the following text for a Grade 8 native English-speaking person.
Original: Magma reached the surface of the volcano about October 11 , 2004 , resulting in the building of a new lava dome on the existing dome 's south side .
Simplified: Magma bubbles came to the top of the volcano on about October 11 , 2004 , and a new lava dome was made on the first dome 's south side .