Taken from the CNRC website:
APPLICANT DRUG AND ALCOHOL ABUSE POLICY
1. Policy. Navy regulations prohibit, except for authorized medical purposes, the introduction, possession, sale or use of narcotic substances and other controlled substances onboard any ship, craft or aircraft of the Department of the Navy, or within any naval activity or other place of jurisdiction of the Department of the Navy. They further prohibit, except for authorized medical purposes, the possession of marijuana, narcotic substances or other controlled substances by persons in the naval service. It is the policy of the Department of the Navy that alcohol/drug dependent personnel or current alcohol/drug abusers will not be permitted to enter the Naval service. However, it is recognized that some people have clear potential to become creditable performers despite limited exposure to alcohol or drug abuse. Recruiting procedures shall include positive measures to screen alcohol/drug abusers at the point of application for admission. They shall also provide an administrative procedure for the granting of pre-service drug abuse waivers to good risk applicants for initial entry into the service.
2. The expanded drug statement is required only when the applicant has admitted drug use or answered "Yes" to drug-related questions on the EPSQ and physical examination forms for applicants of all programs, excluding Nuclear candidates. All Nuclear program candidates shall sign the Submarine and/or Nuclear Propulsion Pre-Service Drug Abuse Statement.
Nuclear Propulsion Programs. No officer or officer candidate will be accepted into the Nuclear Propulsion Program including officers assigned to Naval Reactors' staff, who has:
(1) Been addicted to any illicit drug or is physically or psychologically dependent on any illicit drug or alcohol.
(2) Been a drug trafficker or manufacturer per OPNAVINST 5355.3 series.
(3) Abused illicit drugs (other than cannabis). Note: Waivers for pre-service experimental cannabis use may be granted by CNRC (with Chief of Naval Personnel (Pers-42) concurrence), for Nuclear Propulsion Officer Candidates, Nuclear Power School Instructors, and Naval Reactor Engineers.
(4) During processing and in personal history questioning, the following will be accomplished for applicants for the Navy Nuclear Propulsion Program:
(a) Applicants will acknowledge, by signature, that they may be subject to
further background investigation and that any false statements made during application may subsequently result in removal from the program. The certification will also indicate to what extent the applicant meets the criteria in the above paragraph and will contain a signed statement rejecting the illegal use of drugs.
(b) If the applicant admits to drug abuse and requests consideration, the
following information concerning the circumstances of past drug abuse involvement will be obtained:
1. Type(s) of drug(s) abused;
2. Number of times, approximate dates, and amounts;
3. Period over which taken;
4. Last involvement;
5. Civil involvement.
(c) The Pre-Service Drug Abuse Statement (Annex 8C(7)), shall be used to document the statements made by applicants for nuclear programs regarding drug use. This form will be submitted with the application kit to the appropriate CNRC (Code 31/32/38). CNRC will review all pre-service drug abuse statements and grant waivers, if appropriate (with Pers-42 concurrence). Applicants for these programs may be granted a pre-service drug abuse waiver by CNRC (with the concurrence of Chief of Naval Personnel) for experimental use of marijuana only.
All Non-Nuclear Officer Programs.
a. No individual will be accepted in any officer program, exclusive of the nuclear field programs above, who has:
(1) Been addicted, or physically or psychologically dependent on any drug or
alcohol;
(2) Been a trafficker of illegal drugs;
(3) Abused narcotics;
(4) Abused dangerous drugs;
(5) Abused marijuana within the past year;
b. Pre-service drug abuse waivers may be granted to any applicant for a non-nuclear field officer program who has:
(1) Abused narcotics more than one year previous;
(2) Abused dangerous drugs more than one year previous;
(3) Abused marijuana between six months and one year previous. (Marijuana use only, more than one year previous, does not require a waiver unless civil involvement was associated.) Pre-service drug abuse waiver authority for applicants in non-nuclear related officer programs is CNRC with the concurrence of the DCNO (Manpower, Personnel and Training) (OP-01).
c. No applicant will be considered for a pre-service drug abuse waiver who does not reject further abuse.
d. Those applicants requiring drug waivers will be considered for a pre-service drug abuse waiver based upon the type and extent of drug abuse, expressed attitude toward past and future drug abuse, suitability under the whole-person concept, and the recommendation of the cognizant NAVCRUITDIST CO, XO or OPO.
e. Those applicants who are not eligible for drug waiver consideration under the
parameters stated above are subject to mandatory rejection at the field level. This does not preclude submission of an application at a later date if the pre-service drug abuse waiver criteria can be met at that time.
f. Previous or current alcohol abuse, including documented alcohol-related incidents or offenses, will be a factor in the whole-person evaluation made by the selection board for all officer programs. Although not a mandatory rejection factor, significant history of alcohol abuse is considered a major deterrent to an applicant's qualifications and will normally result in non-selection.
g. Officer candidates in OCS and officers in OIS who are identified as drug abusers by urinalysis or other methods will be disciplined as appropriate and processed for separation. Officer accessions with enlisted status or an enlisted obligation will be immediately disqualified for commissioning and treated as enlisted members for disposition, as appropriate.