SOLUTION TO PRIZE CROSSWORD No 15,646:

ACROSS: 6 Opencast mining. 9 Victim. 10 Salutary. 11 Black ice. 13 Tetchy. 15 Enigma. 17 Terror. 19 Public. 20 Goodwill. 22 Riparian. 24 Ensign. 26 Systems analyst. DOWN: 1 Social security. 2 Neat. 3 Scampi. 4 Omelette. 5 Unit. 7 Sussex. 8 Northern lights. 12 Chill. 14 Throw. 16 Machismo. 18 Uganda. 21 One-way. 23 Arts. 25 Styx.