Is it possible and with due appreciation for installed RAM would it be possible to get Apache Spark running on TX1 and would it be able to make use of the GPUs?
Spark appears to be usable on the Raspberry Pi, so it stands to reason that it would be usable on the Jetson platform. As for porting it to the Jetson platform, I am unaware of any attempts to do so. However, there have been attempts to make it usable with CUDA, so you might want to post this question to our CUDA forums instead:
Also note that OpenCL is often used with Spark, this will not be possible on the Jetson platform.