Program: 25224
Project: 25224
Buggy source:
public void excavationProcCheck(Block block,Player player){
  int type=block.getTypeId();
  Location loc=block.getLocation();
  ItemStack is=null;
  Material mat=null;
  if (type == 3 || type == 13 || type == 2) {
    if (Math.random() * 10 > 9) {
      mcUsers.getProfile(player).skillUpExcavation(1);
      player.sendMessage(ChatColor.YELLOW + "String_Node_Str" + mcUsers.getProfile(player).getExcavationInt()+ "String_Node_Str");
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 750) {
      if (Math.random() * 2000 > 1999) {
        mat=Material.getMaterial(354);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 500 && type == 3) {
      if (Math.random() * 1000 > 999) {
        mat=Material.getMaterial(2256);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
      if (Math.random() * 1000 > 999) {
        mat=Material.getMaterial(2257);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
      if (Math.random() * 500 > 499) {
        mat=Material.getMaterial(264);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
    }
  }
  if (type == 12) {
    if (Math.random() * 10 > 9) {
      mcUsers.getProfile(player).skillUpExcavation(1);
      player.sendMessage(ChatColor.YELLOW + "String_Node_Str" + mcUsers.getProfile(player).getExcavationInt()+ "String_Node_Str");
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 50 && Math.random() * 100 > 95) {
      mat=Material.getMaterial(348);
      is=new ItemStack(mat,1,(byte)0,(byte)0);
      loc.getWorld().dropItemNaturally(loc,is);
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 500 && Math.random() * 500 > 499) {
      mat=Material.getMaterial(264);
      is=new ItemStack(mat,1,(byte)0,(byte)0);
      loc.getWorld().dropItemNaturally(loc,is);
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 125) {
      if (Math.random() * 2000 > 1999) {
        mat=Material.getMaterial(263);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
    }
  }
  if ((type == 2 || type == 3) && mcUsers.getProfile(player).getExcavationInt() > 25) {
    if (Math.random() * 10 > 7) {
      mat=Material.getMaterial(348);
      is=new ItemStack(mat,1,(byte)0,(byte)0);
      loc.getWorld().dropItemNaturally(loc,is);
    }
  }
  if (type == 13 && mcUsers.getProfile(player).getExcavationInt() > 75) {
    if (Math.random() * 10 > 7) {
      mat=Material.getMaterial(289);
      is=new ItemStack(mat,1,(byte)0,(byte)0);
      loc.getWorld().dropItemNaturally(loc,is);
    }
  }
}

Fixed version (ground truth):
public void excavationProcCheck(Block block,Player player){
  int type=block.getTypeId();
  Location loc=block.getLocation();
  ItemStack is=null;
  Material mat=null;
  if (type == 2 && mcUsers.getProfile(player).getExcavationInt() > 250) {
    if (Math.random() * 100 > 99) {
      mat=Material.getMaterial(260);
      is=new ItemStack(mat,1,(byte)0,(byte)0);
      loc.getWorld().dropItemNaturally(loc,is);
    }
  }
  if (type == 3 || type == 13 || type == 2) {
    if (Math.random() * 10 > 9) {
      mcUsers.getProfile(player).skillUpExcavation(1);
      player.sendMessage(ChatColor.YELLOW + "String_Node_Str" + mcUsers.getProfile(player).getExcavationInt()+ "String_Node_Str");
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 750) {
      if (Math.random() * 2000 > 1999) {
        mat=Material.getMaterial(354);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 500) {
      if (Math.random() * 1000 > 999) {
        mat=Material.getMaterial(2256);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
      if (Math.random() * 1000 > 999) {
        mat=Material.getMaterial(2257);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
      if (Math.random() * 500 > 499) {
        mat=Material.getMaterial(264);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
    }
  }
  if (type == 12) {
    if (Math.random() * 10 > 9) {
      mcUsers.getProfile(player).skillUpExcavation(1);
      player.sendMessage(ChatColor.YELLOW + "String_Node_Str" + mcUsers.getProfile(player).getExcavationInt()+ "String_Node_Str");
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 50 && Math.random() * 100 > 95) {
      mat=Material.getMaterial(348);
      is=new ItemStack(mat,1,(byte)0,(byte)0);
      loc.getWorld().dropItemNaturally(loc,is);
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 500 && Math.random() * 500 > 499) {
      mat=Material.getMaterial(264);
      is=new ItemStack(mat,1,(byte)0,(byte)0);
      loc.getWorld().dropItemNaturally(loc,is);
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 125) {
      if (Math.random() * 2000 > 1999) {
        mat=Material.getMaterial(263);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
    }
  }
  if ((type == 2 || type == 3) && mcUsers.getProfile(player).getExcavationInt() > 25) {
    if (Math.random() * 10 > 7) {
      mat=Material.getMaterial(348);
      is=new ItemStack(mat,1,(byte)0,(byte)0);
      loc.getWorld().dropItemNaturally(loc,is);
    }
  }
  if (type == 13) {
    if (mcUsers.getProfile(player).getExcavationInt() > 75) {
      if (Math.random() * 10 > 7) {
        mat=Material.getMaterial(289);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
    }
    if (mcUsers.getProfile(player).getExcavationInt() > 175) {
      if (Math.random() * 10 > 6) {
        mat=Material.getMaterial(352);
        is=new ItemStack(mat,1,(byte)0,(byte)0);
        loc.getWorld().dropItemNaturally(loc,is);
      }
    }
  }
}