kernelfault

Hi everyone, i am having an issue, i forgot to turn off my quarry before i went to bed and now i assume there is a bunch of blocks sitting on the ground lagging me to pieces. I have read somewhere that i can run a command off the Worldedit plugin that will let me remove all items on the ground. I have attempted to run this but can see no options to run this in tekkit. Can someone please tell me how i can run this command? or if i need to download another plugin to make this happen? thanks in advance.