Violations
|
| Violation ID |
Occurred Date |
Violation Type |
(-) Violation Description |
Corrective Action |
Status |
Classification |
Source |
| 1143283 |
03/31/2025 |
DMON |
Radioactivity.
Per the MRP, final effluent shall be analyzed quarterly for radioactivity. At the Pomona WRP, the second quarter grab samples for gross alpha, gross beta, uranium, radium-226, radium-228, tritium, and strontium-90 were not collected due to a Laboratory oversight. Following the Laboratory Information Management System (LIMS) update in November 2024, the Sanitation Districts identified a system issue in which the automated regeneration of sampling events for certain compounds began defaulting to an incorrect interval rather than the intended frequency. The Sanitation Districts¿ LIMS administrator is aware of the issue and is actively working with the system¿s provider to resolve it. As a corrective measure, a separate schedule has been established to ensure these compounds continue to be sampled on a quarterly basis. Make-up samples were collected on April 8, and the results will be reported in the April 2025 monthly compliance report. The Pomona WRP was operating under normal conditions during the month. Thus, the concentrations of the radioactivity compounds in the final effluent are expected to have been within normal ranges.
|
Radioactivity.
Per the MRP, final effluent shall be analyzed quarterly for radioactivity. At the Pomona WRP, the second quarter grab samples for gross alpha, gross beta, uranium, radium-226, radium-228, tritium, and strontium-90 were not collected due to a Laboratory oversight. Following the Laboratory Information Management System (LIMS) update in November 2024, the Sanitation Districts identified a system issue in which the automated regeneration of sampling events for certain compounds began defaulting to an incorrect interval rather than the intended frequency. The Sanitation Districts¿ LIMS administrator is aware of the issue and is actively working with the system¿s provider to resolve it. As a corrective measure, a separate schedule has been established to ensure these compounds continue to be sampled on a quarterly basis. Make-up samples were collected on April 8, and the results will be reported in the April 2025 monthly compliance report. The Pomona WRP was operating under normal conditions during the month. Thus, the concentrations of the radioactivity compounds in the final effluent are expected to have been within normal ranges.
|
Violation |
U |
eSMR |
| 1142110 |
01/05/2025 |
OEV |
Total Coliform 7-Day Median limit is 2.2 CFU/100 mL and reported value was 2.4 CFU/100 mL at EFF-001. |
Per Section 4.1 of the WDR, the wastes discharged shall be adequately disinfected at all times such that the 7-day median number of total coliform bacteria shall not exceed 2.2 Most Probable Number (MPN) or Colony Forming Units (CFU) per 100 milliliters (mL) utilizing the bacteriological results of the last seven (7) days for which an analysis has been completed. The total coliform density exceeded the 7-day median limit of 2.2 CFU/100 mL on January 4 and 5 with a value of 2.4 CFU/100 mL. All other total coliform permit limitations were met (i.e., the number of total coliform bacteria did not exceed 23 CFU/100 mL in more than one sample within any 30-day period, and no samples exceeded 240 CFU/100 mL). The Sanitation Districts investigated the cause of these exceedances and findings suggested that the samples collected at the Pomona WRP for total coliform analysis may have been impacted by skimmings and debris floating on the water surface of the chlorine contact tanks, from which the samples were collected. The operation of the floating skimming equipment, which typically removes excess surface debris from the chlorine contact tanks, was temporarily changed from a continuous to a periodic operation during Summer 2024 in order to maximize the amount of recycled water available for non-potable reuse due to construction activities at the Pomona WRP during that time. This appears to have resulted in the formation of a thin layer of skimmings accumulating near the end of the tank which may have caused sample contamination when the sample bottle was lowered into the tank through the thin skimmings layer. To prevent reoccurrence, the skimming equipment was operated on a full-time basis beginning January 8. Please see the cover letter for more details. |
Violation |
U |
eSMR |
| 1141158 |
01/05/2025 |
OEV |
Total Coliform 7-Day Median limit is 2.2 CFU/100 mL and reported value was 2.4 CFU/100 mL at EFF001 WRR. |
The Sanitation Districts investigated the cause of these exceedances and findings suggested that the samples collected at the Pomona WRP for total coliform analysis had been impacted by skimmings and debris on the water surface of the chlorine contact tanks, from which the samples were collected. During the past summer the operation of the floating skimming equipment, which typically removes excess surface debris in the chlorine contact tanks, was temporarily changed from a continuous to a periodic operation to maximize the amount of recycled water available for non-potable reuse due to construction activities at the plant during the summer months. This appears to have resulted in the formation of a thin layer of skimmings accumulating near the end of the tank which may have caused sample contamination when the sample bottle was lowered in the tank through the thin skimmings layer. Effluent that is discharged to the San Jose Creek is pulled from lower in the chlorine contact tanks and is not expected to be impacted by the thin skimmings layer. Therefore, these total coliform results may not be representative of actual effluent water quality.
To prevent reoccurrence, the skimming equipment was reactivated on a full-time basis beginning January 8. In addition, the Sanitation Districts evaluated if a new sampling location, downstream of the skimming equipment and closer to the effluent weir, would be more representative of effluent water quality. Starting February 12, the total coliform sampling location at the Pomona WRP was relocated to downstream of the skimming equipment and closer to the effluent weir of the chlorine contact tanks to better ensure results representative of current treatment. Please see cover letter for more details.
|
Violation |
U |
eSMR |
| 1142109 |
01/04/2025 |
OEV |
Total Coliform 7-Day Median limit is 2.2 CFU/100 mL and reported value was 2.4 CFU/100 mL at EFF-001. |
Per Section 4.1 of the WDR, the wastes discharged shall be adequately disinfected at all times such that the 7-day median number of total coliform bacteria shall not exceed 2.2 Most Probable Number (MPN) or Colony Forming Units (CFU) per 100 milliliters (mL) utilizing the bacteriological results of the last seven (7) days for which an analysis has been completed. The total coliform density exceeded the 7-day median limit of 2.2 CFU/100 mL on January 4 and 5 with a value of 2.4 CFU/100 mL. All other total coliform permit limitations were met (i.e., the number of total coliform bacteria did not exceed 23 CFU/100 mL in more than one sample within any 30-day period, and no samples exceeded 240 CFU/100 mL). The Sanitation Districts investigated the cause of these exceedances and findings suggested that the samples collected at the Pomona WRP for total coliform analysis may have been impacted by skimmings and debris floating on the water surface of the chlorine contact tanks, from which the samples were collected. The operation of the floating skimming equipment, which typically removes excess surface debris from the chlorine contact tanks, was temporarily changed from a continuous to a periodic operation during Summer 2024 in order to maximize the amount of recycled water available for non-potable reuse due to construction activities at the Pomona WRP during that time. This appears to have resulted in the formation of a thin layer of skimmings accumulating near the end of the tank which may have caused sample contamination when the sample bottle was lowered into the tank through the thin skimmings layer. To prevent reoccurrence, the skimming equipment was operated on a full-time basis beginning January 8. Please see the cover letter for more details. |
Violation |
U |
eSMR |
| 1141157 |
01/04/2025 |
OEV |
Total Coliform 7-Day Median limit is 2.2 CFU/100 mL and reported value was 2.4 CFU/100 mL at EFF001 WRR. |
The Sanitation Districts investigated the cause of these exceedances and findings suggested that the samples collected at the Pomona WRP for total coliform analysis had been impacted by skimmings and debris on the water surface of the chlorine contact tanks, from which the samples were collected. During the past summer the operation of the floating skimming equipment, which typically removes excess surface debris in the chlorine contact tanks, was temporarily changed from a continuous to a periodic operation to maximize the amount of recycled water available for non-potable reuse due to construction activities at the plant during the summer months. This appears to have resulted in the formation of a thin layer of skimmings accumulating near the end of the tank which may have caused sample contamination when the sample bottle was lowered in the tank through the thin skimmings layer. Effluent that is discharged to the San Jose Creek is pulled from lower in the chlorine contact tanks and is not expected to be impacted by the thin skimmings layer. Therefore, these total coliform results may not be representative of actual effluent water quality.
To prevent reoccurrence, the skimming equipment was reactivated on a full-time basis beginning January 8. In addition, the Sanitation Districts evaluated if a new sampling location, downstream of the skimming equipment and closer to the effluent weir, would be more representative of effluent water quality. Starting February 12, the total coliform sampling location at the Pomona WRP was relocated to downstream of the skimming equipment and closer to the effluent weir of the chlorine contact tanks to better ensure results representative of current treatment. Please see cover letter for more details.
|
Violation |
U |
eSMR |
| 1135640 |
09/26/2024 |
DMON |
Per Section I of the MRP, recycled water shall be analyzed daily for settleable solids. The settleable solids result for the recycled water sample collected on September 26 was invalidated because the analyst did not read the result within the method's required analysis time. To prevent reoccurrence, Laboratory staff was reminded of the analysis requirement. Throughout the month, the Pomona WRP was operating under normal conditions and settleable solids results were all not detected (ND). Therefore, this result is expected to have been within normal range and to have been in compliance with the permit limits.
|
Per Section I of the MRP, recycled water shall be analyzed daily for settleable solids. The settleable solids result for the recycled water sample collected on September 26 was invalidated because the analyst did not read the result within the method's required analysis time. To prevent reoccurrence, Laboratory staff was reminded of the analysis requirement. Throughout the month, the Pomona WRP was operating under normal conditions and settleable solids results were all not detected (ND). Therefore, this result is expected to have been within normal range and to have been in compliance with the permit limits.
|
Violation |
U |
eSMR |
| 1135639 |
09/03/2024 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 157 mg/L at EFF001 WRR. |
Per Section A.2 of the WRRs, the daily maximum chloride concentration of recycled water shall not exceed 150 mg/L. A recycled water sample collected from the Pomona WRP on September 3 had a chloride concentration of 157 mg/L, which exceeds the daily limit. Chloride loadings to the Pomona WRP can come from various residential and industrial sources, chemicals added during wastewater treatment, and the potable water supply. Plant operation was normal at the time of the exceedance and no cause of the elevated chloride result was identified.
Reduced sewer flows due to water conservation have the potential to concentrate community loadings, resulting in higher plant influent chloride concentrations, and consequently, elevated effluent chloride concentrations. The supply water within the drainage area of the Pomona WRP consists of a blend of groundwater and surface water from the Metropolitan Water District's Weymouth Water Filtration Plant (WFP), and, overall, the chloride concentrations from the Weymouth WFP have been rising. This increase in chloride from the Weymouth WFP water as well as reduced sewer flows may be driving increases in effluent chloride concentration at the Pomona WRP. The Sanitation Districts will continue to monitor this constituent and, if necessary, will investigate and examine additional possible sources.
|
Violation |
U |
eSMR |
| 1135995 |
08/31/2024 |
CTOX |
Chronic Toxicity-C.dubia-Reproduction Monthly Median limit is 0 Pass/Fail (Pass = 0, Fail = 1) and reported value was 1 Pass/Fail (Pass = 0, Fail = 1) at EFF-001. |
The chronic toxicity tests conducted in August have been invalidated. Initially, the tests resulted in an MMEL exceedance. However, in October 2024, the San Jose Creek Water Quality Laboratory (SJCWQL) determined that all Ceriodaphnia dubia (C. dubia) test organisms used by SJCWQL for chronic toxicity testing were compromised between July and September 2024 and thus invalidated all of the C. dubia chronic toxicity tests conducted by SJCWQL during this period. Therefore, the MMEL exceedance in August has not been substantiated by valid testing and is considered not to have occurred. Numerical toxicity testing results values included in the CDF of this report are included for Regional Board's informational purposes, but are considered invalid. C. dubia compliance toxicity testing was immediately contracted to Enthalpy Analytical from October through December 2024 while SJCWQL determined necessary corrective actions. SJCWQL will implement comprehensive corrective actions to address the contamination issue and establish quality control measures before resuming in-house C. dubia chronic toxicity testing. Complete documentation of all C. dubia toxicity tests, reference toxicant tests, operational data, and industrial waste data will be provided in a final TRE report. |
Violation |
U |
eSMR |
| 1134449 |
08/01/2024 |
DMON |
Per Section I of the MRP, recycled water shall be analyzed daily for total coliform. The total coliform result for the recycled water sample collected on August 1 was invalid because the micro incubator fell out of temperature range during a planned electrical shutdown on August 2, preventing the analysis from being finalized. While the confirmation test for the sample analysis in process during that time is invalid, the presumptive result remains valid, although no confirmed results can be reported. The total coliform results were non-detectable (ND) in August, except on August 6 (2 CFU/100 mL) and 30 (1 CFU/100 mL). Therefore, this result is expected to have been within normal range and to have been in compliance with the permit limits. |
Per Section I of the MRP, recycled water shall be analyzed daily for total coliform. The total coliform result for the recycled water sample collected on August 1 was invalid because the micro incubator fell out of temperature range during a planned electrical shutdown on August 2, preventing the analysis from being finalized. While the confirmation test for the sample analysis in process during that time is invalid, the presumptive result remains valid, although no confirmed results can be reported. The total coliform results were non-detectable (ND) in August, except on August 6 (2 CFU/100 mL) and 30 (1 CFU/100 mL). Therefore, this result is expected to have been within normal range and to have been in compliance with the permit limits. |
Violation |
U |
eSMR |
| 1131901 |
07/30/2024 |
DMON |
Per Section I of the MRP, recycled water shall be analyzed daily for total coliform. The total coliform result for the recycled water sample collected on July 30 was invalid because the micro incubator fell out of temperature range during a planned electrical shutdown on August 2, preventing the analysis from being finalized. While the confirmation test for the sample analysis in process during that time is invalid, the presumptive result remains valid, although no confirmed results can be reported. Throughout July, the coliform results ranged were all non-detectable (ND). Therefore, this result is expected to have been within normal range and to have been in compliance with the permit limits. |
Per Section I of the MRP, recycled water shall be analyzed daily for total coliform. The total coliform result for the recycled water sample collected on July 30 was invalid because the micro incubator fell out of temperature range during a planned electrical shutdown on August 2, preventing the analysis from being finalized. While the confirmation test for the sample analysis in process during that time is invalid, the presumptive result remains valid, although no confirmed results can be reported. Throughout July, the coliform results ranged were all non-detectable (ND). Therefore, this result is expected to have been within normal range and to have been in compliance with the permit limits. |
Violation |
U |
eSMR |
| 1129425 |
05/09/2024 |
DMON |
Per the MRP, effluent shall be monitored daily for total coliform. On May 9, the total coliform result was invalidated due to a laboratory error in which the analyst misread the setup time and read the results 30 minutes before 22-24 hour read time. To prevent reoccurrence, Laboratory staff will ask questions if unsure about handwriting and take more time to read the setup time. Pomona WRP was operating under normal conditions during the month. Thus, the total coliform concentration in the effluent on this day is expected to have been within normal range and in compliance with effluent limitations. |
Per the MRP, effluent shall be monitored daily for total coliform. On May 9, the total coliform result was invalidated due to a laboratory error in which the analyst misread the setup time and read the results 30 minutes before 22-24 hour read time. To prevent reoccurrence, Laboratory staff will ask questions if unsure about handwriting and take more time to read the setup time. Pomona WRP was operating under normal conditions during the month. Thus, the total coliform concentration in the effluent on this day is expected to have been within normal range and in compliance with effluent limitations. |
Violation |
U |
eSMR |
| 1128599 |
04/10/2024 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 157 mg/L at EFF001 WRR. |
Per Section A.2 of the WRRs, the daily maximum chloride concentration of recycled water shall not exceed 150 mg/L. On April 10, a recycled water sample collected from the Pomona WRP had a chloride concentration of 157 mg/L, which exceeds the daily limit. Chloride loadings to the Pomona WRP can come from various residential and industrial sources, chemicals added during wastewater treatment, and the potable water supply. Plant operation was normal at the time of the exceedance and no cause of the elevated chloride result was identified.
Reduced sewer flows due to water conservation have the potential to concentrate community loadings, resulting in higher plant influent chloride concentrations, and consequently, elevated effluent chloride concentrations. The supply water within the drainage area of the Pomona WRP consists of a blend of groundwater and surface water from the Metropolitan Water District's Weymouth Water Filtration Plant (WFP), and, overall, the chloride concentrations from the Weymouth WFP have been rising. This increase in chloride from the Weymouth WFP water as well as reduced sewer flows may be driving increases in effluent chloride concentration at the Pomona WRP. The Sanitation Districts will continue to monitor this constituent and, if necessary, will investigate and examine additional possible sources. |
Violation |
U |
eSMR |
| 1128592 |
03/31/2024 |
DMON |
Per Section 4 of the MRP, effluent samples shall be analyzed quarterly for oil and grease. The quarterly effluent grab sample for oil and grease was inadvertently not analyzed due to laboratory oversight. The next quarterly oil and grease monitoring is scheduled for June and the result will be reported in the appropriate monthly monitoring report. To prevent a recurrence of this issue, laboratory staff have reviewed and revised procedures for tracking samples. During this period, the Pomona WRP was operating under normal conditions; thus, this parameter is expected to be within normal range on this day. |
Per Section 4 of the MRP, effluent samples shall be analyzed quarterly for oil and grease. The quarterly effluent grab sample for oil and grease was inadvertently not analyzed due to laboratory oversight. The next quarterly oil and grease monitoring is scheduled for June and the result will be reported in the appropriate monthly monitoring report. To prevent a recurrence of this issue, laboratory staff have reviewed and revised procedures for tracking samples. During this period, the Pomona WRP was operating under normal conditions; thus, this parameter is expected to be within normal range on this day. |
Violation |
B |
eSMR |
| 1127444 |
03/05/2024 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 169 mg/L at EFF001 WRR. |
Per Section A.2 of the WRRs, the daily maximum chloride concentration of recycled water shall not exceed 150 mg/L. On March 5, a recycled water sample collected from the Pomona WRP had a chloride concentration of 169 mg/L, which exceeds the daily limit. Chloride loadings to the Pomona WRP can come from various residential and industrial sources, chemicals added during wastewater treatment, and the potable water supply. Plant operation was normal at the time of the exceedance and no cause of the elevated chloride result was identified.
Reduced sewer flows due to drought conditions and water conservation have the potential to concentrate community loadings, resulting in higher plant influent chloride concentrations, and consequently, elevated effluent chloride concentrations. The supply water within the drainage area of the Pomona WRP consists of a blend of groundwater and surface water from the Metropolitan Water District¿s Weymouth Water Filtration Plant (WFP), and, overall, the chloride concentrations from the Weymouth WFP have been rising. This increase in chloride from the Weymouth WFP water as well as reduced sewer flows may be driving increases in effluent chloride concentration at the Pomona WRP. The Sanitation Districts will continue to monitor this constituent and, if necessary, will investigate and examine additional possible sources.
|
Violation |
U |
eSMR |
| 1125029 |
01/08/2024 |
Order Conditions |
An unauthorized recycled water discharge of a maximum of 9,000 gallons occurred on January 8 from roughly 7:10 a.m. to 7:30 a.m. at the Sanitation Districts' Spadra Landfill located at 4125 West Valley Boulevard in the city of Walnut. The Sanitation Districts notified the Regional Board at 3:45 p.m. on January 8, with a follow up letter on January 12. The unauthorized discharge originated from a below-grade recycled water distribution line near Bench 5 of the landfill on the southwestern side of the facility. The discharge occurred due to a crack in a Victaulic pipe connection fitting which allowed the line to separate, discharging recycled water into the soil. The pipe separation led to surface runoff downslope and into the storm drain prior to the pipeline being isolated. The leak was observed at approximately 7:10 a.m. on January 8, and continued until approximately 7:30 a.m. the same day, when site staff isolated the line. Recycled water was discharged into the soil until it became saturated, emanated from the surface and began to flow approximately 400 feet down the bench road before entering a catch basin. The discharge then flowed another approximately 600 feet before entering a Los Angeles County Department of Public Works storm drain. This storm drain ultimately discharges into the San Jose Creek. The recycled water produced at the Pomona WRP is suitable for discharge to the San Jose Creek per its National Pollutant Discharge Elimination System permit (Order No. R4-2021-0097), therefore no impacts to public health or the environment are expected. Staff reported that there was little flow in the San Jose Creek channel and there were no indications that fish or wildlife had been adversely impacted; therefore, there were no observed biological impacts from the discharge. To minimize reoccurrence of similar events, the Sanitation Districts will investigate the installation of above-grade recycled water lines and initiate a Victaulic fitting inspection program. |
To minimize reoccurrence of similar unauthorized recycled water discharge events, the Sanitation Districts will investigate the installation of above-grade recycled water lines and initiate a Victaulic fitting inspection program. |
Violation |
U |
eSMR |
| 1125030 |
01/04/2024 |
DMON |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on January 4 was invalidated due to a laboratory error in which the analyst left the bacterial culture tubes outside of the incubator after the 24-hours read time. All other coliform results for the month were either non-detect or 1 CFU/100 mL, therefore, this result was expected to be within normal ranges. Laboratory staff were reminded of proper procedures. |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on January 4 was invalidated due to a laboratory error in which the analyst left the bacterial culture tubes outside of the incubator after the 24-hours read time. All other coliform results for the month were either non-detect or 1 CFU/100 mL, therefore, this result was expected to be within normal ranges. Laboratory staff were reminded of proper procedures. |
Violation |
U |
eSMR |
| 1122428 |
10/11/2023 |
DMON |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on October 11 was invalidated because of improper sample incubation procedure. The analyst failed to write down the read time on the lab bench sheet and was unable to verify the correct duration of the incubation period. Throughout the month, the coliform results were typically non-detectable, except for five separate instances in which it was recorded at 1 CFU/100mL. Therefore, this result was expected to be within normal range and in compliance with the WRRs. To prevent a recurrence of this issue, Laboratory staff will double check that the sample data is properly filled out on the bench sheet. |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on October 11 was invalidated because of improper sample incubation procedure. The analyst failed to write down the read time on the lab bench sheet and was unable to verify the correct duration of the incubation period. Throughout the month, the coliform results were typically non-detectable, except for five separate instances in which it was recorded at 1 CFU/100mL. Therefore, this result was expected to be within normal range and in compliance with the WRRs. To prevent a recurrence of this issue, Laboratory staff will double check that the sample data is properly filled out on the bench sheet. |
Violation |
U |
eSMR |
| 1121673 |
09/23/2023 |
DMON |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on September 23 was invalidated because of improper sample incubation procedure. Throughout the month, the coliform results were typically non-detectable, except for one instance in which it was recorded at 2 CFU/100 mL and three other separate instances where it was recorded at 1 CFU/100 mL. Therefore, this result was expected to be within normal range. To prevent a recurrence of this issue, Laboratory senior staff revisited the procedure with the analyst. |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on September 23 was invalidated because of improper sample incubation procedure. Throughout the month, the coliform results were typically non-detectable, except for one instance in which it was recorded at 2 CFU/100 mL and three other separate instances where it was recorded at 1 CFU/100 mL. Therefore, this result was expected to be within normal range. To prevent a recurrence of this issue, Laboratory senior staff revisited the procedure with the analyst. |
Violation |
U |
eSMR |
| 1120968 |
08/21/2023 |
DMON |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on August 21 was invalidated because the bacterial plate was discarded by the lab analyst before confirming two colonies. All other coliform results for the month were either non-detect or, in one occurrence, 2 CFU/100 mL, therefore, this result was expected to be within normal ranges. To prevent a recurrence of this issue, Laboratory senior staff revisited the procedure with the analyst. |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on August 21 was invalidated because the bacterial plate was discarded by the lab analyst before confirming two colonies. All other coliform results for the month were either non-detect or, in one occurrence, 2 CFU/100 mL, therefore, this result was expected to be within normal ranges. To prevent a recurrence of this issue, Laboratory senior staff revisited the procedure with the analyst. |
Violation |
U |
eSMR |
| 1120972 |
07/24/2023 |
DMON |
Per Section 4 of the MRP, effluent samples shall be analyzed daily for Total Residual Chlorine. The Total Residual Chlorine result from the effluent sample collected on July 24 was invalid because the sample was not analyzed within the appropriate laboratory holding time. A make-up sample could not be collected due to lack of effluent flow after initial collection. Laboratory staff have reviewed procedures for tracking samples during handling and to complete analyses within the required holding time in the future. During this period, the Pomona WRP was operating under normal conditions; thus, this parameter is expected to be within normal range on this day. |
Per Section 4 of the MRP, effluent samples shall be analyzed daily for Total Residual Chlorine. The Total Residual Chlorine result from the effluent sample collected on July 24 was invalid because the sample was not analyzed within the appropriate laboratory holding time. A make-up sample could not be collected due to lack of effluent flow after initial collection. Laboratory staff have reviewed procedures for tracking samples during handling and to complete analyses within the required holding time in the future. During this period, the Pomona WRP was operating under normal conditions; thus, this parameter is expected to be within normal range on this day. |
Violation |
B |
eSMR |
| 1120040 |
06/07/2023 |
DMON |
Per Section 8.1 of the MRP, samples shall be collected semiannually for Mercury. Due to laboratory oversight, samples collected on June 7 from receiving water stations RSW-001D (R-A), RSW-002D (R-C) and RSW-003D (R-D) were invalidated because an older analytical method was used analyze the samples. To prevent this oversight from reoccurring, laboratory personnel have updated internal procedures to specify the correct sampling method for mercury. Make-up samples were collected on July 20, 2023 and results will be included in the July report. |
Per Section 8.1 of the MRP, samples shall be collected semiannually for Mercury. Due to laboratory oversight, samples collected on June 7 from receiving water stations RSW-001D (R-A), RSW-002D (R-C) and RSW-003D (R-D) were invalidated because an older analytical method was used analyze the samples. To prevent this oversight from reoccurring, laboratory personnel have updated internal procedures to specify the correct sampling method for mercury. Make-up samples were collected on July 20, 2023 and results will be included in the July report. |
Violation |
B |
eSMR |
| 1117819 |
04/05/2023 |
DMON |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on April 5 was invalidated because the test initiation time was not properly recorded. All other coliform results for the month were either non-detect or 1 CFU/100 mL, therefore, this result was expected to be within normal ranges. Laboratory staff were reminded of proper recording and review procedures. |
Per Section I of the MRP, recycled water samples shall be analyzed daily for total coliform. The total coliform result in the recycled water sample collected on April 5 was invalidated because the test initiation time was not properly recorded. All other coliform results for the month were either non-detect or 1 CFU/100 mL, therefore, this result was expected to be within normal ranges. Laboratory staff were reminded of proper recording and review procedures. |
Violation |
U |
eSMR |
| 1115393 |
02/07/2023 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 155 mg/L at EFF001 WRR. |
Per Section A.2 of the WRRs, the daily maximum chloride concentration of recycled water shall not exceed 150 mg/L. On February 7, a recycled water sample collected from the Pomona WRP had a chloride concentration of 155 mg/L, which exceeds the daily limit. Chloride loadings to the Pomona WRP can come from various residential and industrial sources, chemicals added during wastewater treatment, and the potable water supply. Plant operation was normal at the time of the exceedance and no cause of the elevated chloride result was identified. Reduced sewer flows due to drought conditions and water conservation have the potential to concentrate community loadings, resulting in higher plant influent chloride concentrations, and consequently, elevated effluent chloride concentrations. The supply water within the drainage area of the Pomona WRP consists of a blend of groundwater and surface water from the Metropolitan Water District¿s Weymouth Water Filtration Plant (WFP), and, overall, the chloride concentrations from the Weymouth WFP have been rising. This increase in chloride from the Weymouth WFP water as well as reduced sewer flows may be driving increases in effluent chloride concentration at the Pomona WRP. The Sanitation Districts will continue to monitor this constituent and, if necessary, will investigate and examine additional possible sources. |
Violation |
U |
eSMR |
| 1114555 |
01/03/2023 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 151 mg/L at EFF001 WRR. |
Per Section A.2 of the WRRs, the daily maximum chloride concentration of recycled water shall not exceed 150 milligrams per liter (mg/L). On January 3, a recycled water sample collected from the Pomona WRP had a chloride concentration of 151 mg/L, which exceeds the daily limit. Chloride loadings to the Pomona WRP can come from various residential and industrial sources, chemicals added during wastewater treatment, and the potable water supply. Plant operation was normal at the time of the exceedance and no cause of the elevated chloride result was identified. Reduced sewer flows due to drought conditions and water conservation have the potential to concentrate community loadings, resulting in higher plant influent chloride concentrations, and consequently, elevated effluent chloride concentrations. The supply water within the drainage area of the Pomona WRP consists of a blend of groundwater and surface water from the Metropolitan Water District¿s Weymouth Water Filtration Plant (WFP), and, overall, the chloride concentrations from the Weymouth WFP have been rising. This increase in chloride from the Weymouth WFP water as well as reduced sewer flows may be driving increases in effluent chloride concentration at the Pomona WRP. The Sanitation Districts will continue to monitor this constituent and, if necessary, will investigate and examine additional possible sources. |
Violation |
U |
eSMR |
| 1113244 |
12/06/2022 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 153 mg/L at EFF001 WRR. |
Per Section A.2 of the WRRs, the daily maximum chloride concentration of recycled water shall not exceed 150 milligrams per liter (mg/L). On December 6, a recycled water sample collected from the Pomona WRP had a chloride concentration of 153 mg/L, which exceeds the daily limit. Chloride loadings to the Pomona WRP can come from various residential and industrial sources, chemicals added during wastewater treatment, and the potable water supply. Plant operation was normal at the time of the exceedance and no cause of the elevated chloride result was identified. Reduced sewer flows due to drought conditions and water conservation have the potential to concentrate community loadings, resulting in higher plant influent chloride concentrations, and consequently, elevated effluent chloride concentrations. The supply water within the drainage area of the Pomona WRP consists of a blend of groundwater and surface water from the Metropolitan Water District's Weymouth Water Filtration Plant (WFP), and, overall, the chloride concentrations from the Weymouth WFP have been rising. This increase in chloride from the Weymouth WFP water as well as reduced sewer flows may be driving increases in effluent chloride concentration at the Pomona WRP. The Sanitation Districts will continue to monitor this constituent and, if necessary, will investigate and examine additional possible sources. |
Violation |
U |
eSMR |
| 1109906 |
09/06/2022 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 159 mg/L at EFF001 WRR. |
Per Section A.2 of the WRRs, the daily maximum chloride concentration of recycled water shall not exceed 150 milligrams per liter (mg/L). On September 6, a recycled water sample collected from the Pomona WRP had a chloride concentration of 159 mg/L, which exceeds the daily limit. Chloride loadings to the Pomona WRP can come from various residential and industrial sources, chemicals added during wastewater treatment, and the potable water supply. Plant operation was normal at the time of the exceedance and no cause of the elevated chloride result was identified. Reduced sewer flows due to drought conditions and water conservation have the potential to concentrate community loadings, resulting in higher plant influent chloride concentrations, and consequently, elevated effluent chloride concentrations. The supply water within the drainage area of the Pomona WRP consists of a blend of groundwater and surface water from the Metropolitan Water District¿s Weymouth Water Filtration Plant (WFP), and, overall, the chloride concentrations from the Weymouth WFP have been rising. This increase in chloride from the Weymouth WFP water may be driving increases in effluent chloride concentration at the Pomona WRP. The Sanitation Districts will continue to monitor this constituent and, if such exceedances continue, will investigate and examine additional possible sources. |
Violation |
U |
eSMR |
| 1109187 |
08/13/2022 |
DMON |
Per Section I of the MRP, recycled water shall be analyzed daily for total coliform. Total coliform results from recycled water samples collected on August 13 and 14 were invalid because expired media was inadvertently used during laboratory analysis. To prevent this issue from re-occurring, laboratory staff will ensure that the correct media is used for total coliform analyses. The Pomona WRP was operating under normal conditions during the month. Thus, total coliform concentrations in the final effluent are expected to have been within normal ranges. |
Per Section I of the MRP, recycled water shall be analyzed daily for total coliform. Total coliform results from recycled water samples collected on August 13 and 14 were invalid because expired media was inadvertently used during laboratory analysis. To prevent this issue from re-occurring, laboratory staff will ensure that the correct media is used for total coliform analyses. The Pomona WRP was operating under normal conditions during the month. Thus, total coliform concentrations in the final effluent are expected to have been within normal ranges. |
Violation |
U |
eSMR |
| 1109205 |
07/07/2022 |
DMON |
Per Section 8.1 of the MRP, receiving water samples shall be analyzed monthly for nitrate, nitrite, nitrate plus nitrite, and total nitrogen. Nitrate, nitrite, nitrate plus nitrite, and total nitrogen results from a receiving water sample collected at RSW-001D (R-A) on July 7 were invalid because the sample was not analyzed within the appropriate laboratory holding time. The sample collected from RSW-001D was inadvertently switched with another sample prior to analysis, and by the time laboratory staff noticed the error, the RSW-001D sample was outside of the holding time and therefore not analyzed. A make-up sample was collected on September 7 and the results will be included in the corresponding report. Laboratory staff have reviewed procedures for tracking samples during handling and to complete analyses within the required holding time in the future. |
Per Section 8.1 of the MRP, receiving water samples shall be analyzed monthly for nitrate, nitrite, nitrate plus nitrite, and total nitrogen. Nitrate, nitrite, nitrate plus nitrite, and total nitrogen results from a receiving water sample collected at RSW-001D (R-A) on July 7 were invalid because the sample was not analyzed within the appropriate laboratory holding time. The sample collected from RSW-001D was inadvertently switched with another sample prior to analysis, and by the time laboratory staff noticed the error, the RSW-001D sample was outside of the holding time and therefore not analyzed. A make-up sample was collected on September 7 and the results will be included in the corresponding report. Laboratory staff have reviewed procedures for tracking samples during handling and to complete analyses within the required holding time in the future. |
Violation |
B |
eSMR |
| 1103732 |
04/16/2022 |
LREP |
Annual SMR ( PRETRPT ) report for 2021 (2416175) was due on 15-APR-22 |
|
Violation |
B |
Report |
| 1097864 |
10/05/2021 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 151 mg/L at EFF001 WRR. |
Per Section A.2 of the WRRs, the daily maximum chloride concentration of recycled water shall not exceed 150 milligrams per liter (mg/L). A recycled water sample collected from the Pomona WRP on October 5 was measured to have a chloride concentration of 151 mg/L, which exceeds the 150 mg/L daily limit. Chloride loadings to the Pomona WRP come from residential sources, industrial sources, chemicals added during wastewater treatment, and water supplied to the community. Plant operation was normal at the time of the exceedance and no cause of the elevated chloride result was identified. The Sanitation Districts will continue to monitor water quality in the recycled water and will conduct further investigations into potential causes, such as inspections of industrial waste dischargers, if future concentrations exceed the permit threshold. |
Violation |
U |
eSMR |
| 1099032 |
10/01/2021 |
DMON |
Per Section 8 of the MRP, receiving water samples shall be analyzed monthly for bromoform, chloroform, dichlorobromomethane, dibromochloromethane, and total trihalomethanes. Receiving water samples were not collected for these constituents during the month of October due to a laboratory error in scheduling the sample collection. This scheduling error was associated with the new monitoring and reporting requirements of Order R4-2021-0097, which became effective in August 2021. Laboratory staff have reviewed their sample collection schedules, have updated those schedules accordingly, and began monthly sample collection for these constituents in November. |
Per Section 8 of the MRP, receiving water samples shall be analyzed monthly for bromoform, chloroform, dichlorobromomethane, dibromochloromethane, and total trihalomethanes. Receiving water samples were not collected for these constituents during the month of October due to a laboratory error in scheduling the sample collection. This scheduling error was associated with the new monitoring and reporting requirements of Order R4-2021-0097, which became effective in August 2021. Laboratory staff have reviewed their sample collection schedules, have updated those schedules accordingly, and began monthly sample collection for these constituents in November. |
Violation |
U |
eSMR |
| 1097946 |
09/01/2021 |
DMON |
Per Section 8 of the MRP, receiving water samples shall be analyzed monthly for bromoform, chloroform, bromodichloromethane, dibromochloromethane, and total trihalomethanes. Receiving water samples were not collected for these constituents during the month of September due to a laboratory error in scheduling the sample collection. This scheduling error was associated with the new monitoring and reporting requirements of Order R4-2021-0097, which became effective in August 2021. Laboratory staff have reviewed their sample collection schedules and have updated those schedules accordingly. |
Per Section 8 of the MRP, receiving water samples shall be analyzed monthly for bromoform, chloroform, bromodichloromethane, dibromochloromethane, and total trihalomethanes. Receiving water samples were not collected for these constituents during the month of September due to a laboratory error in scheduling the sample collection. This scheduling error was associated with the new monitoring and reporting requirements of Order R4-2021-0097, which became effective in August 2021. Laboratory staff have reviewed their sample collection schedules and have updated those schedules accordingly. |
Violation |
U |
eSMR |
| 1091924 |
05/29/2021 |
DMON |
Results from a recycled water sample collected on May 29 were invalid because the 24-hour composite was comprised of less than 12 aliquots. This issue was caused by a laboratory staff error in running the autosampler equipment; staff were alerted to the error and have been reminded of proper procedures. |
Results from a recycled water sample collected on May 29 were invalid because the 24-hour composite was comprised of less than 12 aliquots. This issue was caused by a laboratory staff error in running the autosampler equipment; staff were alerted to the error and have been reminded of proper procedures. |
Violation |
U |
eSMR |
| 1088869 |
02/28/2021 |
DMON |
Per Section I of the MRP, Pomona WRP recycled water samples shall be collected daily for total coliform monitoring. A Pomona WRP recycled water sample was collected on February 28 but not analyzed for total coliform because the sample exceeded the appropriate holding time prior to analysis. |
To prevent this issue from re-occurring, laboratory staff will modify procedures for tracking samples that still require analysis. |
Violation |
U |
eSMR |
| 1088879 |
01/03/2021 |
DMON |
Per Section IV.A.2 of the MRP, additional effluent samples shall be collected and analyzed for residual chlorine if the residual chlorine meter reads greater than 0.3 mg/L for more than five minutes. On January 3 at approximately 5:47 a.m., the residual chlorine meter in the final effluent exceeded 0.5 mg/L for over five minutes. Operations staff identified the cause as a blockage in the feed line for the sodium bisulfite dechlorinating agent and restored the bisulfite flow at approximately 6:30 a.m. Plant operators collected a grab sample from the final effluent at 7:38 a.m. following the incident and sent it to the laboratory for analysis. Laboratory staff analyzed the chlorine residual concentration in the sample and noted the concentration was non-detect. However, because the laboratory staff erroneously believed the sample was only being used for operational control, they did not record the sample result using their standard protocols. Thus, there is no official documentation of the sample collected January 3 at 7:38 a.m. following the chlorine residual exceedance. To prevent this issue from re-occurring, notification and sample collection procedures have been reviewed with operational and laboratory supervisory staff. |
Per Section IV.A.2 of the MRP, additional effluent samples shall be collected and analyzed for residual chlorine if the residual chlorine meter reads greater than 0.3 mg/L for more than five minutes. On January 3 at approximately 5:47 a.m., the residual chlorine meter in the final effluent exceeded 0.5 mg/L for over five minutes. Operations staff identified the cause as a blockage in the feed line for the sodium bisulfite dechlorinating agent and restored the bisulfite flow at approximately 6:30 a.m. Plant operators collected a grab sample from the final effluent at 7:38 a.m. following the incident and sent it to the laboratory for analysis. Laboratory staff analyzed the chlorine residual concentration in the sample and noted the concentration was non-detect. However, because the laboratory staff erroneously believed the sample was only being used for operational control, they did not record the sample result using their standard protocols. Thus, there is no official documentation of the sample collected January 3 at 7:38 a.m. following the chlorine residual exceedance. To prevent this issue from re-occurring, notification and sample collection procedures have been reviewed with operational and laboratory supervisory staff. |
Violation |
B |
eSMR |
| 1086036 |
12/06/2020 |
Order Conditions |
An unauthorized discharge of Pomona WRP disinfected tertiary-treated recycled water occurred on December 6, 2020 from approximately 2:13 a.m. to 2:50 a.m. in Rowland Heights, CA near the intersection of Brea Canyon Cut Off Road and Balan Road. The Walnut Valley Water District (end user) reported the discharge to the Los Angeles County Sanitation Districts (Sanitation Districts) on December 16 at 10:54 a.m. The Sanitation Districts confirmed the discharge on December 17 at 11:10 am and provided verbal notification of the event to the Regional Board on the same day at 12:32 p.m. The unauthorized discharge occurred as a result of a car accident near the road intersection on December 6, 2020 at approximately 2:13 a.m. The accident sheared the roadside air vacuum valve and damaged the blow-off line. The estimated total discharge volume is approximately 180,000 gallons based on the size of the recycled water distribution line and duration of the discharge. To reach the nearest receiving water, the recycled water would have had to travel approximately 2.4 miles in the storm drain and discharge into the concrete-lined portion of the San Jose Creek. Residual chlorine in the recycled water would have decayed before reaching the receiving water due to the 2.4-mile travel distance and contact with substances exerting chlorine demand along the storm drain. As a verification measure, staff from the Sanitation Districts' Biological Sciences Group inspected San Jose Creek near the discharge point in Rowland Heights at 1:55 p.m. on December 17. There were no negative biological impacts observed. Because the unauthorized discharge was caused by an unforeseen car accident, additional preventative measures cannot be implemented to prevent a reoccurrence. Walnut Valley staff and Sanitation Districts' staff will review the notification and reporting procedures for unauthorized discharges. |
An unauthorized discharge of Pomona WRP disinfected tertiary-treated recycled water occurred on December 6, 2020 from approximately 2:13 a.m. to 2:50 a.m. in Rowland Heights, CA near the intersection of Brea Canyon Cut Off Road and Balan Road. The Walnut Valley Water District (end user) reported the discharge to the Los Angeles County Sanitation Districts (Sanitation Districts) on December 16 at 10:54 a.m. The Sanitation Districts confirmed the discharge on December 17 at 11:10 am and provided verbal notification of the event to the Regional Board on the same day at 12:32 p.m. The unauthorized discharge occurred as a result of a car accident near the road intersection on December 6, 2020 at approximately 2:13 a.m. The accident sheared the roadside air vacuum valve and damaged the blow-off line. The estimated total discharge volume is approximately 180,000 gallons based on the size of the recycled water distribution line and duration of the discharge. To reach the nearest receiving water, the recycled water would have had to travel approximately 2.4 miles in the storm drain and discharge into the concrete-lined portion of the San Jose Creek. Residual chlorine in the recycled water would have decayed before reaching the receiving water due to the 2.4-mile travel distance and contact with substances exerting chlorine demand along the storm drain. As a verification measure, staff from the Sanitation Districts' Biological Sciences Group inspected San Jose Creek near the discharge point in Rowland Heights at 1:55 p.m. on December 17. There were no negative biological impacts observed. Because the unauthorized discharge was caused by an unforeseen car accident, additional preventative measures cannot be implemented to prevent a reoccurrence. Walnut Valley staff and Sanitation Districts' staff will review the notification and reporting procedures for unauthorized discharges. |
Violation |
U |
eSMR |
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Report displays most recent five years of violations. Refer to the Interactive Violation Report for more data.
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Total Violations: 36
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Priority Violations: 0
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*Click the "(+/-) Violation Description" link to expand and contract the violation description.
*As of 5/20/2010, the Water Board's Enforcement Policy requires that all violations be classified as 1, 2 or 3, with class 1 being the highest. Prior to this, violations were simply classified as Yes or No. If a 123 classification has been assigned to a violation that occurred before this date, that classification data will be displayed instead of the Yes/No data.
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CAT1 = Category 1 Pollutant (Effluent Violation for Group 1 Pollutant)
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CTOX = Chronic Toxicity
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DMON = Deficient Monitoring
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LREP = Late Report
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Order Conditions = Order Conditions
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OEV = Other Effluent Violation
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