Ala. Admin. Code r. 335-7-2-.05

Current through Register Vol. 43, No. 1, October 31, 2024
Section 335-7-2-.05 - Volatile Synthetic Organic Chemicals (VOCs) Standards and Monitoring Requirements
(1) The following are the MCLs for VOCs:

CONTAMINANTMCL (mg/L)
Benzene 0.005
Carbon Tetrachloride 0.005
1,2-dichloroethane 0.005
Trichloroethylene 0.005
para-dichlorobenzene 0.075
1,1-dichloroethylene 0.007
1,1,1-trichloroethane 0.2
Vinyl chloride 0.002
cis-1,2-Dichloroethylene 0.07
1,2-Dichloropropane 0.005
Ethylbenzene 0.7
Monochlorobenzene 0.1
O-Dichlorobenzene 0.6
Styrene 0.1
Tetrachloroethylene 0.005
Toluene 1
Trans-1,2-Dichloroethylene 0.1
Xylene (Total) 10
Dichloromethane 0.005
1,2,4-Trichlorobenzene 0.07
1,1,2-Trichloroethane 0.005

(2) The following are the monitoring requirements for VOCs :
(a) Community and NTNC water systems shall analyze for each VOC during each three year monitoring period if no regulated VOC has been detected in the past. Samples shall be collected during periods of normal operating conditions from the entry point to the distribution system representing each source of water used after any application of treatment. Raw water analysis may be used to determine compliance if no treatment processes are used for the reduction of VOCs.
(b) Community and NTNC water systems shall sample all new sources for VOCs for four consecutive quarters. The system may apply for a waiver for the new source after two quarters of monitoring for any VOC which has not been detected above the monitoring trigger.
(c) Community and NTNC water systems using water from more than one source and blending prior to the entry point to the distribution system must sample at the entry point to the distribution system during periods of normal operating conditions. Sampling of raw water from each source may be required if a contaminant is detected.
(d) Confirmation samples may be required by the Department to confirm a negative or positive result. Confirmation samples must be collected from a point representing the source and unless investigation proves initial samples were contaminated because of conditions at the sampling site or sampling procedures, the confirmation results will be averaged with the initial results to determine compliance.
(e) Community and NTNC water systems may apply to the Department for a waiver from monitoring VOCs. Issuance of the waiver shall be based on established vulnerability criteria, results of water analysis and a demonstration by the system of no use, transport, storage or disposal in the watershed or Source Water Assessment Areas I and II. The waiver, if granted, shall be in effect for two compliance periods and the system must reapply for the waiver every two compliance periods. A system must collect one sample at each sampling point for a VOC analysis during the time frame the waiver is in effect and update the vulnerability assessment within three years after the waiver is granted.
(f) The Department may require analysis of VOCs during a specific quarter of the year.
(g) The Department has the authority to determine compliance based on analytical results and other information compiled by Department staff.
(h) Non compliance with any regulated VOC MCL will occur when:
1. For systems monitoring more than once per year, compliance with the MCL is determined by a running annual average at each sampling point.
2. Any sample analysis exceeds the MCL, if monitoring is being conducted annually or less frequently.
3. Upon exceeding the MCL, the system must establish a treatment process using the EPA approved best available technology to achieve compliance with the MCL or phase out using the source of supply in conjunction with a Department-issued compliance schedule.
4. If one sampling point is in violation of an MCL, the system is in violation of the MCL.
(i) Repeat samples must be analyzed after initial sampling has been completed according to the following schedule:
1. Community and NTNC water systems shall monitor for VOCs annually if no regulated VOCs are detected above the monitoring trigger in the initial compliance monitoring.
2. Monitoring may be reduced to one sample per compliance period for ground water systems if no regulated VOCs are detected above the monitoring trigger after a minimum of three years of annual sampling.
3. Monitoring may be reduced to one sample per compliance period for surface water systems if no regulated VOCs are detected above the monitoring trigger after a minimum of three years of annual sampling and the system is determined to be non-vulnerable according to previously approved EPA criteria.
4. If a regulated VOC is detected above the monitoring trigger, community and NTNC water systems must monitor quarterly for VOCs. The system will not be considered in violation of the MCL until it has completed one year of quarterly sampling.
5. Monitoring may be reduced to annually if the average of all analytical results within the past two years is less than one-half of the MCL and no analytical result within the past two years exceeds 75% of the MCL. Groundwater systems shall analyze a minimum of two quarterly samples and surface water systems a minimum of four quarterly samples.
6. Community and NTNC water systems which exceed the MCL for a regulated VOC shall analyze quarterly for that contaminant beginning in the next quarter after the violation occurred. Sampling may be reduced to annually if the average of all analytical results within the past two years is less than one-half of the MCL and no analytical result within the past two years exceeds 75% of the MCL. All community and NTNC water systems must analyze a minimum of four quarterly samples.
7. Community and NTNC water systems which have three consecutive annual sample results with no detection of a regulated volatile organic chemical may apply to the Department for a waiver according to the criteria listed in this chapter.
8. All repeat samples shall be collected at the sampling point where detection occurred.
9. Systems which have detected one or more of the following two-carbon organic compounds: trichloroethylene, tetrachloroethylene, 1,2 dichloroethane, 1,1,1-trichloroethane, cis-1,2 dichloroethylene, trans-1,2-dichloroethylene, or 1,1-dichloroethylene shall monitor quarterly for vinyl chloride. A vinyl chloride sample shall be taken at each sampling point at which one or more of the two-carbon organic compounds were detected. If the results of the first analysis do not detect vinyl chloride, the system shall collect one sample during each compliance period.
(j) Consecutive systems which obtain all of their water from a public water system are exempt from monitoring for the regulated VOCs.
(k) If a system fails to collect the required number of samples, compliance will be based on the total number of samples collected.
(l) If a sample result is less than the detection limit, zero will be used to calculate the annual average.

Ala. Admin. Code r. 335-7-2-.05

New Rule: Filed December 18, 2007; effective January 22, 2008.

Author: Dennis D. Harrison

Statutory Authority:Code of Ala. 1975, §§ 22-23-33, 22-23-49, 22-22A-5, 22-22A-6.