Connecting spark core to an arduino mini

I have 2 sensors that are I2C based, and I am interested in getting both of their data at the same time all the time.
From what I understand, in order to communicate in I2C with the core, I only have D0 and D1, so I can connect only 1 sensor or use a bus, I dont really know what a bus but from what I read online it looks like it will not give me the ability to read both of the sensors and still have high sampling rate (the sensors have 100hz and I would like to keep it)
So I thought to use the mini in order to have the 2 sensors connected and sampled at the same time, do the calculations I want, and send the data to the core, and from there up to the cloud.
Is there a better way, using only the core, to sample both sensors at the same time?

By the way, I just want to say I am very thankful for your help!