La. Admin. Code tit. 51 § XII-1305

Current through Register Vol. 50, No. 9, September 20, 2024

Section XII-1305 - Monthly TOC Monitoring/Reporting

A. Public water systems, meeting §1303. A applicability requirements of this Subchapter, shall submit the results of their paired (source water and treated water) total organic carbon (TOC) samples (which have been collected for compliance determination in accord with the system's approved D/DBPR monitoring plan) to the state health officer monthly for each individual treatment plant. In addition, the result of source water alkalinity sampling conducted at the same time as the source water TOC sample shall also be submitted to the state health officer monthly for each individual treatment plant. The actual monthly TOC percent removal and the removal ratio (reported to two significant figures past the decimal point) shall be calculated in accord with 40 CFR 141.135(c) and indicated on the form. All results for each particular plant shall be on a report form approved by the state health officer. Such report shall specifically be provided to the OPH District Engineering office which has jurisdictional oversight of the public water system within 10 days following the end of each calendar month.

B. When monthly TOC percent removal calculations performed under Subsection A of this Section result in a negative number (indicative of having a higher level of TOC in treated water than in source water), a "0" percent removal shall be reported for that particular paired sample set instead of the negative number. If this should happen, OPH recommends that an additional paired sample set of TOC samples be collected later in that same month. If the system chooses to collect an additional paired sample set of TOC samples during that same month, the system shall mathematically average the "0" result of the first paired sample set with the result of the second paired sample set and report such average as the monthly TOC percent removal achieved on the monthly TOC report form. If the system does not choose to collect an additional paired sample set of TOC samples during that same month, the system shall report a "0" percent removal achieved on the monthly TOC report form.

C. Plant sites having multiple treatment trains shall perform TOC paired monitoring on each treatment train and report the results of each separate treatment train on its own, individual, and properly identified TOC monthly operating report. The actual monthly TOC percent removal and the removal ratio (reported to two significant figures past the decimal point) for the entire plant site shall be determined by performing a flow-weighted average using the results from each individual treatment train. Flow-weighted averaging shall be based upon the flows at the moment in time that the samples are collected. The percent flow attributed to each treatment train shall be reported and shown in the flow-weighted average calculation formula.

1. On a case-by-case basis, a system may apply to DHH-OPH for approval of the use of a flow-weighted sample composite of all treatment trains in lieu of individual TOC analyses of each individual treatment train. The flow-weighted sample shall be composited by laboratory personnel using aliquots from individual samples collected from each treatment train. Flow-weighted averaging shall be based upon the flows at the moment in time that the samples are collected. Each sample composite shall consist of aliquots from no more than five different treatment trains. Each laboratory report of a sample composite shall identify the specific treatment trains associated with the composited sample.

2. On a case-by-case basis, a system may apply to DHH-OPH for a waiver allowing monitoring of only one treatment train at a facility having multiple treatment trains if the system can demonstrate consistency in TOC sample results between each of the different treatment trains located at the facility. If such waiver is granted, it shall be stipulated therein that the waiver shall automatically cease if any treatment changes are made which may affect the continued consistency between TOC sample results between the various treatment trains.

La. Admin. Code tit. 51, § XII-1305

Promulgated by the Department of Health and Hospitals, Office of Public Health, LR 30:1196 (June 2004).

AUTHORITY NOTE: Promulgated in accordance with R.S. 40:4(A)(8) and 40:5(2)(3)(5)(6)(17)(20).