R317-4-10. Wastewater Holding Tanks Administrative, Design, and Installation

10.1. Administrative Requirements.

A. Requests for the use of wastewater holding tanks shall receive the written approval of the local health department prior to the installation of the holding tank and be administered under an annual operating permit.

B. Wastewater holding tanks are only permitted:

1. where an absorption system for an existing dwelling has failed and installation of a replacement absorption system is not practicable;

2. as a temporary, not to exceed one year, wastewater system for a new dwelling until a connection is made to an approved sewage collection system;

3. as a temporary, not to exceed one year, wastewater system that may include construction sites, labor camps, temporary mass gatherings, or emergency refuge sheltering; or

4. for other essential and unusual situations where both the division and the local health department having jurisdiction concur that the proposed holding tank will be designed, installed and maintained in a manner that provides long term protection of the waters of the state.

a. Requests for the use of wastewater holding tanks in this instance shall receive the written approval of both agencies prior to the installation of such devices.

C. Except on those lots recorded and approved for wastewater holding tanks prior to May 21, 1984, wastewater holding tanks are not permitted for use in new housing subdivisions, or commercial, institutional, and recreational developments except in those instances where these devices are part of a specific watershed protection program acceptable to the division and the local health department having jurisdiction.

10.2. General Requirements.

The design, site placement, installation, and maintenance of all wastewater holding tanks shall comply with the following:

A. No wastewater holding tank shall be installed and used unless plans and specifications covering its design and construction have been submitted to and approved by the appropriate regulatory authority.

B. A statement accompanying the application, that a contract with an approved pumper per Rule R317-550 will be obtained stating that the tank will be pumped out periodically at regular intervals or as needed, and contents will be disposed in an approved manner.

C. If authorization is necessary for disposal of wastewater at certain facilities, evidence of such authorization must be submitted for review.

10.3. Basic Plan Information Required.

Depending on the individual site and circumstances, or as determined by the regulatory authority, some or all of the following plan information may be required.

A. Applicant Information.

1. The name, current address, and telephone number of the applicant.

2. Complete address, legal description of the property, or both, to be served by this onsite wastewater system.

B. A plot or site plan showing:

1. direction of North;

2. daily wastewater flow;

3. location and liquid capacity of wastewater holding tank;

4. source and location of water supply;

5. location of water service line and building sewer; and

6. location of streams, ditches, watercourses, ponds, etc., near property.

C. Plan detail of wastewater holding tank and high wastewater level warning device.

D. Relative elevations of:

1. building floor drain;

2. building sewer;

3. invert of inlet for tank;

4. lowest plumbing fixture or drain in building served; and

5. the maximum liquid level of the tank.

E. Statement indicating the maximum anticipated ground water table.

10.4. Construction.

A. The tank shall be constructed of sound and durable material not subject to excessive corrosion and decay and designed to withstand hydrostatic and external loads. All wastewater holding tanks shall comply with the manufacturing materials and construction requirements specified for septic tanks.

B. Construction of the tank shall be such as to assure water tightness and to prevent the entrance of rainwater, surface drainage or ground water.

C. Tanks shall be provided with a maintenance access manhole at the ground surface or above and of at least 18 inches in diameter. Access covers shall have adequate handles and shall be designed and constructed in such a manner that they cannot pass through the access opening, and when closed will be child-proof and prevent entrance of surface water, dirt, or other foreign material, and seal the odorous gases in the tank.

D. A high water warning device shall be installed on each tank to indicate when it is within 75% of being full.

1. This device shall be either an audible or a visual alarm.

a. If the latter, it shall be conspicuously mounted.

2. All wiring and mechanical parts of such devices shall be corrosion resistant.

3. All conduit passage ways through the tank top or walls shall be water and vapor tight.

E. No overflow, vent, or other opening shall be provided in the tank other than those described above.

F. The regulatory authority may require that wastewater holding tanks be filled with water and allowed to stand overnight to check for leaks. Tanks exhibiting obvious defects or leaks may not be approved unless such deficiencies are repaired to the satisfaction of the regulatory authority.

G. The building sewer shall comply with this rule.

H. Above ground holding tanks shall be clearly labeled as "Sewage".

10.5. Capacity.

The liquid capacity of the wastewater holding tank shall be based on wastewater flows for the type of dwelling or facility being served as identified in Section R317-4-13 Table 3 and on the desired time period between each pumping.

A. The minimum capacity of underground wastewater holding tanks shall be 1,000 gallons.

10.6. Location.

Any wastewater holding tank must be located:

A. in an area readily accessible to the pump truck in any type of weather that is likely to occur during the period of use;

B. in accordance with the requirements for septic tanks as specified in Section R317-4-13 Table 2; and

C. where it will not tend to float out of the ground due to a high ground water table or a saturated soil condition, since it will be empty or only partially full most of the time. In areas where the ground water table may be high enough to float the tank out of the ground when empty or partially full, adequate ground anchoring procedures shall be provided.

10.7. Management.

A. Wastewater holding tanks shall be pumped periodically, at regular intervals or as needed, and the wastewater contents shall be disposed of in a manner and at a facility meeting the approval of the appropriate regulatory authority.

B. Wastewater holding tanks for seasonal dwellings should be pumped out before each winter season to prevent freezing and possible rupture of the tank.

C. A record of the liquid waste hauler, pumping dates, and amounts pumped shall be maintained and made available to the appropriate regulatory authorities upon request.

D. Wastewater holding tanks shall be checked at frequent intervals by the owner or occupant and if leakage is detected it shall be immediately reported to the regulatory authority.

E. Repairs or replacements shall be conducted under the direction of the regulatory authority.

F. Improper location, construction, operation, or maintenance of a particular holding tank may result in appropriate legal action against the owner by the regulatory authority having jurisdiction.

G. Each holding tank installed under this rule, shall be inspected upon renewal of the operating permit.