Yes; there are very severe restrictions. My hon. friend is receiving protests about the use of asphalts, and I am receiving protests from cities which would like to use tarvia. However, they are not permitted to do so, because restrictions are severe with respect to the use of petroleum products on roads. I was surprised to read that asphalt pavements are being laid. I had thought that was prohibited, but I may be wrong. I shall be glad to get the regulations and advise my hon. friend as to what the prohibition is. But tarvia, and products of that kind, cannot be used.