What does it mean when two notes of the same pitch with different lengths occupy the same space? In this example, the F-A-C chord should take up the third beat of the measure. It seems to be tied to a F-A-C-E eighth note chord of the next measure. How do I account for what appears to be a pair of eighth notes (C-E) at the end of the first measure?
To me, this looks like a way of differentiating voices. It's hard to read some of that, but the written text seems to indicate a harp is playing those chords and a flute is playing the eighth note melody
It's a piano/conductor score, not a piano part. It clearly shows what the woodwind are doing and what the harp is doing. If the harp started on D instead of C, you wouldn't be worried. Well, it starts on C.
But even in music written to be specifically played on keyboard, this sort of thing often happens when two melodic lines share the same pitch. The composer is showing the musical structure. The player copes!