| (a) Septic tank effluent filters. Effective 180 days
after the effective date of these rules, all effluent filters that
are installed in septic tanks shall be listed and approved under the
NSF International Standard 46 (2000) or under any standard approved
by the executive director.
(b) Pump tanks. Pump tanks may be necessary when the
septic tank outlet is at a lower elevation than the disposal field
or for systems that require pressure disposal. All requirements in §285.32(b)(1)(D)
- (F) of this title (relating to Criteria for Sewage Treatment Systems)
also apply to pump tanks. The pump tank shall be constructed according
to the following specifications.
(1) Pump tank criteria. When effluent must be pumped
to a disposal area, an appropriate pump shall be placed in a separate
water-tight tank or chamber. A check valve may be required if the
disposal area is above the pump tank. The pump tank shall be equipped
to prevent siphoning. The tank shall be provided with an audible and
visible high water alarm. If an electrical alarm is used, the power
circuit for the alarm shall be separate from the power circuit for
the pump. Batteries may be used for back-up power supply only. All
electrical components shall be listed and labeled by Underwriters
Laboratories (UL). At the discretion of the permitting authority,
leak testing using water filled to the inside level of the tank lid
or to the top of the riser(s) may be required.
(2) Pump tank sizing. Pump tanks shall be sized to
contain one-third of a day's flow between the alarm-on level and the
inlet to the pump tank. The capacity above the alarm-on level may
be reduced to four hours average daily flow if the pump tank is equipped
with multiple pumps. See §285.33(d)(2)(G)(iii) of this title
(relating to Criteria for Effluent Disposal Systems) for sizing of
pump tanks for surface application systems.
(3) Pump specifications. A single pump may be used
for hydraulic flows equal to or less than 1,000 gallons per day. Dual
pumps are required for hydraulic flows greater than 1,000 gallons
per day. A dual pump system shall have the "alarm on" level below
the "second pump on" level, and shall have a lock-on feature in the
alarm circuit so that once it is activated it will not go off when
the second pump draws the liquid level below the "alarm on" level.
All audible and visible alarms shall have a manual "silence" switch.
The pump switch-gear shall be set such that each pump operates as
the first pump on an alternating basis. All pumps shall be rated by
the manufacturer for pumping sewage or sewage effluent.
(4) Equalization tanks. In addition to the requirements
for pump tanks in this section, equalization tanks shall meet the
following criteria:
(A) The equalization tank must be preceded by a pretreatment
tank.
(B) If an equalization tank is serving residences,
the tank shall have a volume between the pump intake level and the
high water level of at least 50% of the design flow and be designed
to time dose at equal intervals and equal doses throughout a 24-hour
period. The tank may contain a gravity line located above the high
water alarm level which allows flow to the aerobic treatment unit.
The design will use no fewer than 12 doses throughout the 24-hour
period.
(C) If an equalization tank is designed to equalize
flows over periods longer than a 24-hour period, the tank shall be
designed to time dose at equal intervals and equal doses over the
flow equalization time period. The design shall have a storage between
the highest wastewater flow line during the period and the high level
alarm equal to at least 20% of the flow generated during peak days.
The tank may contain a gravity line located above the high water alarm
level which allows flow to the aerobic treatment unit.
(c) Electrical wiring. All electrical wiring and their
conduits shall conform to the requirements of the National Electric
Code (1999) or under any other standards approved by the executive
director. Additionally, all external wiring shall be installed in
approved, rigid, non-metallic gray code electrical conduit. The conduit
shall be buried according to the requirements in the National Electrical
Code and terminated at a main circuit breaker panel or sub-panel.
The permitting authority may approve up to four feet of external wiring
to be contained in water-tight, flexible electrical conduit between
the buried wire and the circuit breaker panel or sub-panel. Any external
wiring that exceeds four feet must be contained in rigid, non-metallic
gray code electrical conduit. Connections shall be in approved junction
boxes. All electrical components shall have an electrical disconnect
within direct vision from the place where the electrical device is
being serviced. Electrical disconnects must be weatherproof (approved
for outdoor use) and have maintenance lockout provisions.
(d) Grease interceptors. Grease interceptors shall
be used on kitchen waste-lines from institutions, hotels, restaurants,
schools with lunchrooms, and other buildings that may discharge large
amounts of greases and oils to the OSSF. Grease interceptors shall
be structurally equivalent to, and backfilled according to, the requirements
established for septic tanks under §285.32(b)(1)(D) - (F) of
this title. The interceptor shall be installed near the plumbing fixture
that discharges greasy wastewater and shall be easily accessible for
cleaning. Grease interceptors shall be cleaned out periodically to
prevent the discharge of grease to the disposal system. Grease interceptors
shall be properly sized and installed according to the requirements
of the 2000 edition of the Uniform Plumbing Code, the 1980 EPA Design
Manual: Onsite Wastewater Treatment and Disposal Systems, or other
prevailing code.
(e) Holding tanks. Tanks shall be constructed according
to the requirements established for septic tanks under §285.32(b)(1)(D)
- (E) of this title. Inlet fittings are required. No outlet fitting
shall be provided. A baffle is not required. Holding tanks shall be
used only on sites where other methods of sewage disposal are not
feasible (these holding tank provisions do not apply to portable toilets
or to an office trailer at a construction site). All holding tanks
shall be equipped with an audible and visible alarm to indicate when
the tank has been filled to within 75% of its rated capacity. A port
with its smallest dimension being at least 12 inches shall be provided
in the tank lid for inspection, cleaning, and maintenance. This port
shall be accessible from the ground surface and must be easily removable
and watertight.
(1) Minimum capacity. The minimum capacity of the holding
tank shall be sufficient to store the estimated or calculated daily
wastewater flow for a period of one week (wastewater usage rate in
gallons per day x seven days).
(2) Location. Holding tanks shall be installed in an
area readily accessible to a pump truck under all weather conditions,
and at a location that meets the minimum distance requirements in §285.91(10)
of this title (relating to Tables).
(3) Pumping requirements. A scheduled pumping contract
with a waste transporter, holding a current registration with the
executive director, must be provided to the permitting authority before
a holding tank may be installed. Pumping records must be retained
for five years.
(f) Composting toilets. Composting toilets will be
approved by the executive director provided the system has been tested
and certified under NSF International Standard 41 (1999) or under
any other standards approved by the executive director.
(g) Condensation. If condensate lines are plumbed directly
into an OSSF, the increased water volume must be accounted for (added
to the usage rate) in the system planning materials.
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| Source Note: The provisions of this §285.34 adopted to be effective February 5, 1997, 22 TexReg 1114; amended to be effective June 13, 2001, 26 TexReg 4115; amended to be effective September 11, 2008, 33 TexReg 7536; amended to be effective December 27, 2012, 37 TexReg 9947; amended to be effective July 6, 2023, 48 TexReg 3508 |
