Looks like they got you...
"B. No internal combustion engine shall be operated at any time or place in the Town of Royalton without an adequate muffler designed and manufactured to suppress exhaust noises to a minimum for the vehicle."
but how do they get the $350 fine?
"§ 95-4
Penalties for offenses.
A violation of this chapter is an offense punishable by a fine of not more than $250. Each day's violation shall constitute a separate offense."
it would be tough to keep your noise from staying within the boundary's of your property...you say she has Horses, can you hear them...maybe you find the noise of a horses whinne /neigh emotionally disturbing.