Potomac Speleological Club

Access Procedures

Read all the access procedures, rules and waivers before contacting the manager about gaining access. 

Trip leaders must be at least 21 years of age. 

The safety of your group is YOUR responsibility. The Sinnett-Thorn Cave Conservancy (STCC) manager is not a safety officer. The owner and STCC want people to enjoy the cave, but we need to know if you meet the entry requirements. Not everybody gains access. 

Read and follow all National Speleological Society guidelines for caving and equipment. The links are available on the STCC homepage.

Maps of the cave, directions to the cave and cave guides are not provided by STCC.

Read, print, and send all three pages of the Sinnett waiver located through the homepage. If you plan on going through the gated Thorn entrance (this is not the Connection), you need to read and print the Thorn Addendum (PDF) in addition to the Sinnett waiver. If you have any problems, please contact the STCC manager at the e-mail address listed on the Rules page.

The manager will communicate only with the trip leader. Do not have trip members contact the manager. For youth groups, the contact/trip leader is the cave guide and is not necessarily the group leader.

The completed original signed waiver must be received before the combination is given. Copies, faxes, and promises are not accepted. Please have participants complete a second waiver, with original signatures, so that if the first gets lost in the mail (and this has happened) you can quickly send the back-up. If there is a problem getting all the cavers to sign a single form, have the cavers download their own individual copy off the website, sign it, and send it directly to the STCC manager with a note listing the date and the name of the trip leader.

Keep the total number of participants between 4 and 10. No more than 10, no less than 4.

Get the waivers to the manager at least one week before your trip. Several groups have waited until the last minute to send the waivers and did not gain access because of mistakes made in signing the waivers. In one case the waiver, sent overnight express, was received a month after the scheduled trip. This group did not gain access. Please be sure to waive the signature requirement when sending the waivers express or overnight mail. The manager may not be at home to sign a receipt and your paperwork will not be picked up at the post office. STCC needs to have time to review the information and to e-mail a confirmation. Your procrastination is not the manager’s emergency.

BIRTH-YEARS (year only: not the month or day) for all participants under 21 years of age must be included. Parental signatures, birthdates AND the signatures of the minors who enter the cave are also required. The parent CANNOT sign for the minor. Please don’t send birthdates for those over 21 years of age and older.

STCC is not responsible for verifying that the waiver is correctly completed by each person. This is the responsibility of the trip leader. If an individual does not complete the waiver correctly, they are not allowed to access the property.

When a correctly filled-out waiver has been received the trip leader will receive the combination the Tuesday night before the trip. Do not share this combination with anyone until you are entering the cave! If the combination is not received by the Tuesday night before your trip, contact the cave manager as soon as possible. This may indicate that there is a problem with the waivers.

When a waiver is received by STCC, the trip leader will be sent an e-mail that lists all individuals who have permission to go. All cavers under 21 years of age will be listed separately and noted as such. If a name is left off the list or is not correctly designated as being under 21 years of age, you MUST notify the STCC access manager as soon as possible so that person may receive permission to enter the cave. If an individual is not listed correctly on the STCC response to the waiver, that person does not have permission to enter the cave or the property to the entrance.

If someone is not sure they are going, have them sign the waiver anyway! Having fewer people on a trip than originally intended is not a problem as long as the minimum group number (4) and ratios of experienced cavers to novices meet the STCC requirements. Ask the STCC access manager about including more than 10 people on the waiver if that would help with planning your trip. Your group will still be limited to 10 people max to enter the cave.

Gaining access to the gated Thorn entrance (not the Connection) requires special permission and the use of the Thorn Addendum. The lock on the Thorn entrance requires a combination that is not the same as the combination for Sinnett. If permission to enter the Thorn entrance is given and you do not receive 2 combinations (one for Sinnett and another for Thorn), you need to contact the manager.

Individuals entering Sinnett may not access the property to the Thorn entrance unless each has received prior and specific written permission from STCC to enter the Thorn properties. There are BULLS which may present a danger in the pastures leading up to this entrance.

Boy Scout leaders must read and adhere to all BSA regulations and NSS guidelines which are available through the STCC homepage. According to BSA regulations, Boy Scout groups are limited to ten participants. This includes the adult leaders and cave guides. Boy Scout cave guides must list their current BSA vertical work certification. All BSA groups must have vertical work certification to enter the cave. No exceptions.

Youth group leaders must read and adhere to all National Speleological Society (NSS) guidelines in addition to all of their parent organization’s regulations and guidelines.

Trip leaders need to answer the following questions when they first contact STCC for cave access. These questions must be answered in the first e-mail to the manager. Experienced cavers are those who have been on at least 5 wild (not commercial) cave trips and are at least 18 years of age. There must be at least one experienced caver for every 4 novice cavers, and all groups need at least two experienced cavers in order to enter the cave. If an experienced caver is unable to make the trip and your group doesn’t meet the requirements, you are not allowed entry onto the properties.

  1. Have you been in Sinnett-Thorn before? If so, what year(s) and how approximately how many times?
  2. How many participants plan on entering the cave?
  3. Describe (very briefly, but with specifics to include cave names, dates, etc.) your caving experience and that of two of your experienced cavers, one of whom may be yourself. 
  4. How many novices vs. experienced cavers?
  5. What group or grotto are you associated with?
  6. What is the purpose of your trip?
  7. Are you an NSS member and, if so, what is your number?
  8. Please list your phone number and address.
  9. What dates do you want? List them in order of preference.