| units per 100 milliliters of water or a fecal coliform effluent limitation
of 200 colony forming units per 100 milliliters water, per grab sample,
in accordance with paragraph (1) of this subsection.
(5) Unless otherwise specified in a permit, chemical
disinfection is not required for stabilization ponds when the total
retention time in the free-water-surface ponds (based on design flow)
is at least 21 days.
(h) Effluent limitations for bacteria.
(1) To demonstrate the disinfection level in effluent
discharged into water in the state by its wastewater treatment facility,
a permittee shall measure the amount of bacteria in the effluent.
(A) E. coli must be
the indicator bacteria measured for discharges to fresh water.
(B) Enterococci must be the indicator bacteria measured
for discharges to salt water.
(2) The monthly average bacteria effluent limitation
in a Texas Pollutant Discharge Elimination System (TPDES) permit must
be the applicable geometric mean for the most stringent contact recreation
category as specified in Chapter 307 of this title (relating to Texas
Surface Water Quality Standards).
(3) The daily maximum bacteria effluent limitation
in a TPDES permit must be the applicable single grab sample for the
most stringent contact recreation category in Chapter 307 of this
title.
(i) More stringent requirements. The commission may
impose more stringent requirements in permits than those specified
in subsections (a) - (h) of this section, on a case-by-case basis,
where appropriate to maintain desired water quality levels or protect
human health.
|
| Source Note: The provisions of this §309.3 adopted to be effective March 19, 1990, 15 TexReg 1160; amended to be effective June 5, 1998, 23 TexReg 5723; amended to be effective July 5, 2006, 31 TexReg 5336; amended to be effective November 26, 2009, 34 TexReg 8327; amended to be effective January 9, 2020, 45 TexReg 370 |
