What is export data pump worker doing when create table sys.ET$nnnnnnnnn

listing datapump workers I find this process that appears to be hung:

 1819 (DW08) Data Pump Worker        WAITING       PX Deq: Execute Reply              199 CREATE TABLE "SYS"."ET$071BAA720001"   ( "ID",  "CREATED",  "QUICK_KEY",  "EVENT_LEVEL",  "CLASSNAME",  "LINE_NUM

I have never encountered this worker wait except on one production database; I am hoping this error is due to high amount of OLTP activity, but am not sure.

Can anyone provide an explanation of what this activity is and why it might possibly be hung? I've watched this process before, and it has waited almost an hour before I kill the export datapump process.