Большой англо-русский и русско-английский словарь
firm ground
Англо-русский словарь технических терминов
compact ground, firm ground, solid ground, coherent material, compact material, firm soil
Русско-английский политехнический словарь
compact ground, firm ground, solid ground, coherent material, compact material, firm soil
* * *
stiffish soil
Dictionnaire technique russo-italien
terreno compatto