12 Va. Admin. Code § 5-590-383

Current through Register Vol. 41, No. 8, December 2, 2024

Section 12VAC5-590-383 - Organic chemicals compliance

A. When the results of sampling indicate positive results for contaminants listed in Table 340.2, the owner shall collect a confirmation sample at the same sampling point within two weeks of notification of the analytical results of the first sample.

B. The results of the initial and confirmation samples shall be averaged to determine waterworks compliance in accordance with subsection C of this section. The department has the discretion to delete results of obvious sampling errors.

C. Compliance with Table 340.2 shall be determined based on the analytical results obtained at each sampling point. A sample result below the detection limit shall be calculated as zero for the purposes of determining the annual average. If the owner fails to collect the required number of samples, then compliance (average concentration) shall be based on the total number of samples collected.

1. For the owner of a waterworks that conducts monitoring more frequently than annually, compliance is determined by an RAA of all samples collected at each sampling point. If the annual average of any sampling point is greater than the PMCL, then the waterworks is out of compliance. If the initial sample or a subsequent sample would cause the annual average to be exceeded, then the waterworks is out of compliance immediately. A sample result below the detection limit shall be calculated as zero for purposes of determining the annual average.

2. If the owner is conducting monitoring annually or less frequently, then the owner is not in violation if the average of the initial and confirmation samples is greater than the PMCL for that contaminant; however, the owner shall begin quarterly sampling. The owner will not be considered in violation of the PMCL until one year of quarterly sampling has been completed and the RAA is exceeded. If any sample will cause the RAA to exceed the PMCL at any sampling point, then the waterworks is immediately out of compliance with the PMCL.

12 Va. Admin. Code § 5-590-383

Derived from Virginia Register Volume 37, Issue 20, eff. 6/23/2021.

Statutory Authority: §§ 32.1-12 and 32.1-170 of the Code of Virginia.