Boulder Creek flows south into the west end of Surprise Lake about 17 kilometres northeast of the community of Atlin. The stream is about 6 kilometres long and braids into three separate streams near its mouth where most of the placer work has been done. From the years 1898 to 1945, 1920 kilograms of gold were taken from the creek (Bulletin 28). The creek was extensively hydraulic mined at the lower end and has received a resurgence of work in the 1980s. It is the third largest producer in Atlin.

The headwaters of the creek are located within a fine grained alaskite body of the Late Cretaceous Surprise Lake batholith (Surprise Lake Plutonic Suite). The creek then flows out of the pluton and over Upper Paleozoic ultramafic and volcanic rocks of the Cache Creek Complex. The volcanic rocks belong to the upper Mississippian to Permian Nakina Formation and comprise mafic greenstone flows and minor volcanic greywacke. The upper Mississippian to Permian ultramafic rocks are often altered to serpentinite.

Most of the gold was taken from the lower end of the creek and very little at the upper end where it flows over the batholith. There is significant placer wolframite in Boulder Creek and several wolframite showings in areas surrounding the headwaters of the creek.

Hydraulic mining was done on Boulder Creek from 1927 to 1941 and produced most of the gold recovered from the creek. A dam was built on the upper reaches of the creek to supply water for operations lower down.