Good idea to document determination. - Particularly if you conclude you are not subject to the rule. - Not a rule requirement. See Section 2.4 of SPCC guidance document. http://www.epa.gov/emergencies/docs/oil/spcc/guidance/2_Applicability.pdf.
The age of consent is eighteen. With parental consent, parties can marry at age seventeen with the exception that if one party does not have a parent who resides in the state and one party has been a resident in Oregon for at least six months, then no permission is necessary.
You'd have to check your local laws. Age of consent varies state to state and significantly by country. And for minors, there is usually an allowance of a certain number of years difference. For example, if you're under 16 in Alabama, you can have sex with someone 12-years old. Some laws will go into details of what sexual acts are permitted and what sexual acts are not. Ages of consent in North America Don't get too discouraged from the judgmental answers like Quora User's (Madeleine Gallay's).