"You know how it works. Some things happen without you even noticing. You know, a small crack appears where you don’t see it, and suddenly things fall apart for no good reason. Or someguy far away decides something, and by the time you learn of it it’s too late.
Like those windmills outside. I wasn’t really hot on letting them build on my fields, but they told me I got no choice, and gave me some money. And if it’s good for the ‘viroment, then I guess it’s okay. Wind generators they said, produce clean power, important for the future and stuff. I was only a bit scared, when they made the first one, man, that was big! But I got used to them, they don’t bother me anymore.
But there’s the field on the west, Field 7a as they call it. I liked the place, really, had a favourite spot there. But ever since they finished the windmills I just wouldn’t stay there, just… didn’t feel like it. Last year I had a miserable harvest on that field only, this year I think there won’t be any, the corn doesn’t want to grow at all. I really don’t like the place anymore, and I hear the livestock won’t go near it, heck my own dog doesn’t want to! Last time I found a few dead birds there. I don’t know… there’s something strange with that place. Can you take a look at it?"
1. Indeed, someone has manipulated the project. The wind turbines are placed in the shape of a symbol of evil, that drains from all around, and calls upon (fill in your favourite demon, or Cthulhu himself). It is only a matter of time until it gets worse. Field 7a, the ‘eye’ of the symbol, will be the center of events.
2. Seems that the geological survey wasn’t quite thorough. The massive weight of the base has disturbed the bedrock, and small amounts of poisonous gases escape from the earth now. But for once this may be good news - there may be a hydrothermal vent, a source of drinkable mineral water, or even oil! The old farmer could be a rich man.
3. The place was always ‘strange’, an intersection of several minor ley lines. With the technology in place, converting natural power of the elements into energy, a modern wizard found it an interesting source of power for himself. Posing as one of the maintenance crew, he placed numerous charms, crystals, etc. in the towers and on the fields, and uses the field to its full potential. Is there a special reason for going so far, or is he just too power-hungry?
Note: the speaker really refers to wind turbines, and not windmills - but with some changes you could transplant it into a fantasy setting, and actual windmills.
The plot is thought for modern campaigns, ideally with a touch of the supernatural; Shadowrun may work as well.