2. (a) That's probably correct. The vibrations are likely to be a nuisance if A can show that they are actually harming his property to a substantial and unreasonable degree. Appropriate relief would be damages to compensate for the cost of repairs to the plaster and an injunction to prevent heavy trucks from using nearby roads in the future.
In St Helens Smelting v Tipping (1865) 11 ER 1483 a valuable estate was purchased 1.5 miles from a large smelting works. When smelting began, the associated fumes from the works caused damage to the plaintiff's shrubs. The Court held that this was nuisance as there was damage to property.