Texas Administrative Code › Title 30 - ENVIRONMENTAL QUALITY › Part 1 - TEXAS COMMISSION ON ENVIRONMENTAL QUALITY › Chapter 285 - ON-SITE SEWAGE FACILITIES › Subchapter D - PLANNING, CONSTRUCTION, AND INSTALLATION STANDARDS FOR OSSFS › Section 285.34 - Other Requirements

Current through Reg. 49, No. 28; July 12, 2024
(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.