|(a) The purpose of this subchapter is to promulgate
a set of effluent quality limitations for treated domestic sewage
which will be required of permittees as appropriate to maintain water
quality in accordance with the commission's surface water quality
standards. Any incorporation of federal regulations into this chapter
shall apply only to disposal of domestic sewage.
(b) Secondary treatment, with exceptions applicable
to certain stabilization pond systems and other natural systems, is
defined as a minimum reduction of pollutants to meet the quality specified
in Figure: 30 TAC §309.1(b):
(c) Effective April 1988, all permits containing an
ammonia-nitrogen effluent limit are modified to change Biochemical
Oxygen Demand (BOD5 ) to carbonaceous
biochemical oxygen demand (CBOD5 ).
(d) Effective January 1, 1988, any permit containing
a BOD5 effluent limitation may be monitored
and reported as CBOD5 as long as nitrogen
is monitored and reported as ammonia-nitrogen at the same sampling
frequency. If the permit authorizes a discharge to land or an evaporation
pond only, ammonia-nitrogen monitoring and reporting are not required
to change to CBOD5 .
(e) The state of Texas has established a state water
quality management program and a continuing planning process which
sets forth the strategy and procedures for accomplishing the management
program's objectives. Essential elements of the program include updates
of basin plans, total maximum daily loads, and wasteload evaluations
by basin segments. In order to achieve compliance with water quality
standards within certain segments, more stringent effluent quality
limitations other than basic secondary treatment may be required to
protect water quality.
|Source Note: The provisions of this §309.1 adopted to be effective March 19, 1990, 15 TexReg 1160; amended to be effective October 8, 1990, 15 TexReg 5500; amended to be effective June 5, 1998, 23 TexReg 5723; amended to be effective January 9, 2020, 45 TexReg 370