Abstract: Control of the pH of an elastomer-containing emulsion concentrate having an external water phase and an oil phase containing a dissolved elastomer, the oil preferably being an aromatic oil having an aromatic content of at least 50 percent and a viscosity below about 50 SUS at 210.degree. F., within the range of a pH of 1 to 3.5, results in an emulsion concentrate system having improved storage stability. Such an emulsion concentrate system can be let down with water to form a frictionally stable emulsion system useful in the treating of asphalt pavements.