Mine Poppin'

You can complete this achievement during the quest That Airspace is Mine(d)!, on the [storyline=5559] storyline for Sojourner of Azj-Kahet.

If you've already completed this quest, you can still do it straight away on a level 70 alt.
/run print(C_QuestLog.IsQuestFlaggedCompleted(79579))

1. 
   
2. 
   Head to Ruptured Lake, [zone=14752] and find [npc=217133] to take the quest The Second Front.
   /way #2255 29.4 41.6 Kal Smoulderbrow
   
3. 
   
4. Complete the quest, turnin to [npc=212076], and then take the second quest That Airspace is Mine(d)! from the same NPC.
5. 
   
6. Fly through the gold orbs in the area to gain [spell=440220], allowing you to fly through and destroy the mines.
7. 
   
8. Don't turnin, and keep going until you've destroyed 500 for the achievement.
9. 
   

All done :)

The mines each take about 30s to respawn once destroyed.

Edit:
For now, as suggested by Yadilie, you can still do this achievement after you've completed the quest; the golden orbs you fly through to get [spell=440220] are just invisible.

/way #2255 27.89 44.90 1. Right side of the skiff
/way #2255 27.55 45.88 2. Right side of the skiff
/way #2255 29.91 47.25 3. Edge of the rock, just above ground
/way #2255 30.03 42.66 4. Edge of the rock, just above ground
/way #2255 28.81 42.86 5. Edge of the rock, just above ground
/way #2255 30.64 41.25 6. Above tip of pointy rock
/way #2255 29.45 43.54 7. Right of the tip of the big skiff (front)
/way #2255 28.41 40.61 8. Right of the tip of the big skiff (back)

This achievement currently (8/29/24) can be completed at ANY time. Blizzard has simply hidden the golden rings and the orbs can still be collected if you know where they were during the quest / WQ. I used the one at the very tip of the main webbed quest ship. Simply fly over the front tip and you should get the light buff to pop mines. Then get to popping for the 9ish sec you have, then repeat.

UPDATE: This achievement apparently has GROUP wide credit, I helped 2 friends get it and even though I had finished the achievement my pops counted for them. So if you have any friends you can make this even faster by doing it together.

I had a hard time figuring this one out, even with all the fine comments here,
so I decided to make a video that might make it a little easier for you.

Hope you like it.

https://youtu.be/PbYfHXY3xuw