Violations
|
Violation ID |
Occurred Date |
Violation Type |
(-) Violation Description |
Corrective Action |
Status |
Classification |
Source |
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 |
1069324 |
10/04/2019 |
DMON |
Per Section IV.A of the MRP, effluent chlorine residual samples shall be analyzed daily (Monday through Friday, except for holidays). Effluent chlorine residual results on October 4 were invalidated due to an exceedance of the holding time. Because the issue was identified the following day, no make-up samples were collected. As a corrective action, the analyst was reminded of the short holding time. |
Per Section IV.A of the MRP, effluent chlorine residual samples shall be analyzed daily (Monday through Friday, except for holidays). Effluent chlorine residual results on October 4 were invalidated due to an exceedance of the holding time. Because the issue was identified the following day, no make-up samples were collected. As a corrective action, the analyst was reminded of the short holding time. |
Violation |
U |
eSMR |
1065321 |
08/06/2019 |
CAT1 |
Chloride Daily Maximum limit is 150 mg/L and reported value was 186 mg/L at EFF001 WRR. |
A recycled water sample collected from the Pomona WRP on August 6 was measured to have a concentration of 186 mg/L, which exceeded the daily maximum chloride limit of 150 mg/L. 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 the salt loadings from the wastewater treatment processes were within typical levels. The chloride result appears to be anomalously high; this concentration is the highest value in the last 15 years, and the average concentration from January through July of 2019 was 133 mg/L. Industrial Waste (IW) staff at the Sanitation Districts identified a potential the source of the chloride to come from an industrial waste discharger located upstream of the Pomona WRP and will continue to investigate this issue further. The Sanitation Districts will continue to monitor water quality in the effluent and will conduct any necessary inspections of nearby industrial waste dischargers upstream of the Pomona WRP. Reduced sewer flows due to the recent drought conditions and water conservation measures have the potential to concentrate community loadings, resulting in higher plant influent chloride concentrations, and consequently, elevated plant 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 Districts Weymouth Water Filtration Plant (WFP). Overall, since 2011, the chloride concentration from the Weymouth WFP has been steadily rising. The Weymouth WFP effluent chloride average concentrations for 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, and 2019 were 63, 84, 87, 89, 98, 102, 55, 90, and 76 mg/L, respectively (the 2019 average is calculated using data from January through July 2019). |
Violation |
U |
eSMR |
1066625 |
08/06/2019 |
CAT1 |
Chloride Monthly Average (Mean) limit is 180 mg/L and reported value was 186 mg/L at EFF-001. |
Per Section IV.A.1 of the WDR, the average monthly effluent limit (AMEL) for chloride is 180 mg/L. An effluent sample from the Pomona WRP was collected on August 6, 2019, and the measured chloride result of 186 mg/L was provided to Sanitation Districts Compliance staff on September 20, 2019. The Sanitation Districts notified Jeong-Hee Lim, Chief of the Municipal Permitting Unit, of the exceedance via a phone call the same day at 9:22 a.m., and submitted written confirmation of this event to the Regional Board on September 25. The chloride result appears to be anomalously high; the permit limit of 180 mg/L has not been exceeded for at least 15 years, and the average concentration from January through July of 2019 was 133 mg/L. Based on the results of a concurrent monthly effluent chronic toxicity test, the measured chloride level is unlikely to have had any impact on aquatic life: toxicity samples were collected on August 2, 5, and 6, 2019 and no toxicity was observed. Sanitation Districts staff identified a potential source: Master Recycling Center (MRC), an industrial waste discharger that processed off-spec waste and was located upstream of the Pomona WRP. During a July inspection of the facility, staff observed hundreds of packed pickle jars, which could contain high chloride concentrations. MRC's industrial discharge permit was revoked on July 24, and staff from the Sanitation Districts, City of Pomona, and the Pomona Police Department disconnected their industrial waste line on August 1. However, evidence indicated that they continued to discharge to the sewer: chloride concentrations in wastewater samples collected immediately downstream of MRC on August 7 and 14 were 168 mg/L and 597 mg/L, respectively. MRC's sanitary connection was sealed on September 19, 2019, and they are no longer in operation. The Sanitation Districts will continue to monitor effluent water quality and inspect nearby industrial waste dischargers as needed. |
Violation |
B |
eSMR |
1065320 |
07/02/2019 |
CTOX |
Chronic Toxicity Maximum Daily (MDEL) limit is 0 Pass/Fail (Pass = 0, Fail = 1) and reported value was 1 Pass/Fail (Pass = 0, Fail = 1) at EFF-001. |
The Maximum Daily Effluent Limit (MDEL) for chronic toxicity was exceeded at the Pomona Water Reclamation Plant (WRP) for the test initiated on July 3, 2019. In accordance with Section VI.A.2.y of the WDR, the Sanitation Districts notified Jeong-Hee Lim, Chief of the Municipal Permitting Unit, at 1:52 p.m. on July 10, and submitted written confirmation of this event to the Regional Board on July 12, 2019.
A 24-hour effluent composite sample collected July 2 from the Pomona WRP was acutely toxic: complete mortality was observed in undiluted sample within 24-hours of exposure. A semi-quantitative metals scan of the sample indicated silver concentrations of 28.5 µg/L in this sample, but <1 µg/L in the second and third samples collected for the test. The acutely toxic sample was reanalyzed using the quantitative EPA 200.8 test method and found to contain 57.5 µg/L of silver; literature reports that common silver complexes (e.g., silver nitrate) at this level could cause acute toxicity. This elevated level is anomalous; silver concentrations have not been detected above the reporting level (0.2 µg/L) in the Pomona WRP effluent since at least 2010.
Sanitation Districts' industrial waste inspectors were immediately notified of this observation, and identified/interviewed five industrial dischargers that may use silver in their processes. Ultimately, none of the facilities are suspected of being the source of silver, but staff will continue to monitor these locations.
Two additional tests that were conducted in July passed the Test of Significant Toxicity (TST); therefore the median monthly effluent limitation (MMEL) was not exceeded. Although a source has not been identified, evidence indicates that the observed toxicity was caused by silver complexes. As demonstrated by the subsequent samples with low silver concentrations and toxicity tests that passed the TST, this toxicity was episodic in nature and is no longer present. |
Violation |
B |
eSMR |
Report displays most recent five years of violations. Refer to the Interactive Violation Report for more data.
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Total Violations: 27
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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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Violation Types |
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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