Oil production in South American country's very risky (8)
I believe the answer is:
perilous
'very risky' is the definition.
(perilous means dangerous or risky)
'oil production in south american country's' is the wordplay.
'production' indicates an anagram.
'in' is an insertion indicator.
'south american country's' becomes 'Peru's' (country in South America).
'oil' with letters rearranged gives 'ilo'.
'ilo' put inside 'perus' is 'PERILOUS'.
(Other definitions for perilous that I've seen before include "Fraught with danger" , "Hazardous, dangerous" , "Full of danger" , "Hazardous, menacing" , "Risky" .)