Detonator-Chunks ignore collision with my goal

I have my script:

 var Prefabspecial_button_holder : GameObject; //object to spawn item at
 var Prefabspecial_button : GameObject; //powerup spawned
 var firestorm_powerup : GameObject; //powerup pod
 var level_complete : GameObject; //level complete text
 
 function OnTriggerEnter (other : Collider) { 
 
     if (other.gameObject.tag == "Player")
     {
 
     var Prefabspecial_button : GameObject = Instantiate(Prefabspecial_button, GameObject.Find("special_button_holder").transform.position, Quaternion.identity);
     Prefabspecial_button.transform.parent = Prefabspecial_button_holder.transform;
     }
     
     level_complete.renderer.enabled = true;
     
     yield WaitForSeconds (3);
     
     Application.LoadLevel(Application.loadedLevel + 1);
 }

it detects when the player falls into it and level is completed, the problem I am having is that I have on one level objects that explode (using Detonator-Chunks) what is happening is that sometimes the chunk object is hitting the finish and completing the level before the player has even got near.

How do I prevent this?