Why would p0410 code cause a p0440 code?

Awhile back, I got these two codes and advance scanned my computer and said p0440 was tied into p0410. I replaced the air pump and the new hose assembly. The pump works fine but these two codes came back. i think its the 2 check valves but im not sure. ITS NOT THE GAS CAP! What would cause the 2ndary injection system malfunction to make an evap system malfunction?