UCMR Monitoring Results
Unregulated Chemicals for which Monitoring is Required
CDPH [The California Department of Public Health] has a regulation that identifies nine chemicals as unregulated contaminants for which monitoring is required (UCMR). Methods and detection limits for purposes of reporting (DLRs) are presented here. This monitoring was to have been completed by 2003.
The monitoring results from the UCMR process can be used by CDPH for cost estimates for monitoring and treatment, as part of the MCL process, should an MCL be considered appropriate.
CDPH intends to establish MCLs for three of the UCMR chemicals. It is in the process of developing an MCL for perchlorate, and will be developing an MCL for chromium-6, once a public health goal (PHG) is available. CDPH has requested a PHG for 1,2,3-trichloropropane (1,2,3-TCP). (Find out more about PHGs here.)
Findings
Results from UCMR sampling that occurred from 2000 through 2004, as compiled in April 2005, are presented in Tables 1, 2, and 3. Distribution by county is presented for the five organic chemicals (Table 2) and the four inorganics (Table 3):
There are ~16,000 drinking water sources, though not all are subject to UCMR requirements.
Table 1. Results of UCMR analyses (2000-2004) |
||
---|---|---|
. | No. of Sources |
|
UCMR Chemical | Detects | Detects >NL* |
Boron | 3,797** | 152 |
Chromium-6 | 3,482** | --*** |
Dichlorodifluoromethane (Freon 12) | 180 | 0 |
Ethyl tertiary butyl ether (ETBE) | 2 | -- |
Perchlorate | 462 | 275 |
Tertiary amyl methyl ether (TAME) | 0 | -- |
Tertiary butyl alcohol (TBA) | 46 | 12 |
1,2,3-TCP | 405 | 388 |
Vanadium | 5,483** | 146 |
*NL=Notification level, discussed below **The large number of detections reflects the natural occurrence of the chemical. ***Chemical has no notification level. |
Findings by county are presented in Tables 2 and 3. Some chemicals were detected above their notification levels. Notification of local agencies by water systems would be required if subsequent sampling confirmed those levels. (Note that the values presented in Tables 1, 2 and 3, are not based on confirmed findings, only single detections.)
Table 2. Drinking water sources with organic UCMR detections 2000-2004, and detections above notification levels (NLs)* |
||||||||
---|---|---|---|---|---|---|---|---|
County | Freon 12 | ETBE | TAME | TBA | 1,2,3-TCP | |||
. | No. of Sources |
No. >NL |
No. of Sources | No. of Sources | No. of Sources |
No. >NL |
No of Sources | No. >NL |
Alameda | 5 | . | . | . | 1 | . | 1 | 1 |
Amador | . | . | . | . | 1 | 1 | . | . |
Calaveras | . | . | . | . | 1 | 1 | . | . |
El Dorado | . | . | . | . | 1 | . | . | . |
Fresno | 33 | . | . | . | . | . | 72 | 68 |
Kern | 4 | . | . | . | 15 | 7 | 111 | 108 |
Kings | . | . | . | . | . | . | 1 | 1 |
Los Angeles | 65 | . | 1 | . | 4 | . | 48 | 43 |
Madera | . | . | . | . | 1 | . | 3 | 3 |
Merced | . | . | . | . | 1 | . | 28 | 28 |
Monterey | 3 | . | . | . | 1 | . | 5 | 3 |
Orange | 4 | 1 | 1 | 2 | 2 | |||
Riverside | . | . | . | . | . | . | 18 | 17 |
Sacramento | 5 | . | . | . | 2 | 1 | 2 | 2 |
San Benito | . | . | . | . | . | . | 1 | 1 |
San Bernardino | 43 | . | . | . | 4 | . | 28 | 27 |
San Diego | . | . | . | . | 7 | . | 6 | 6 |
San Joaquin | 3 | . | . | . | 1 | . | 14 | 14 |
San Luis Obispo | . | . | . | . | 1 | . | 3 | 2 |
San Mateo | . | . | . | . | . | . | 7 | 7 |
Santa Barbara | . | . | . | . | . | . | 1 | 1 |
Santa Clara | 5 | . | 1 | . | . | . | . | . |
Santa Cruz | . | . | . | . | 2 | . | 2 | 2 |
Shasta | . | . | . | . | 2 | 1 | ||
Solano | . | . | . | . | . | . | 2 | 2 |
Stanislaus | 9 | . | . | . | . | . | 12 | 12 |
Sutter | . | . | . | . | . | . | 3 | 3 |
Tulare | 4 | . | . | . | . | . | 34 | 33 |
Yolo | 1 | . | . | . | . | . | . | . |
Yuba | . | . | . | . | 1 | . | 1 | 1 |
TOTAL | 180 | 0 | 2 | 0 | 46 | 12 | 405 | 388 |
DLR (mg/L) | 0.0005 | . | 0.002 | 0.002 | 0.003 | . | 0.000005 | . |
NL (mg/L) | . | 1 | n/a** | n/a** | . | 0.012 | . | 0.000005 |
*Number of drinking water sources with at least one detection in water sampled 2000-2004. Numbers are considered "draft" because they will change with subsequent updates. ** ETBE and TAME do not have NLs. |
Table 3. Drinking water sources with inorganic UCMR detections 2000-2004, and detections above notification levels (NLs) |
|||||||
---|---|---|---|---|---|---|---|
County | Boron | Cr-6** | Perchlorate | Vanadium | |||
. | No. of Sources |
No. >NL |
No. of Sources |
No. of Sources |
No. >NL |
No. of Sources |
No. >NL |
Alameda | 43 | . | 34 | . | . | 28 | . |
Alpine | 1 | . | . | . | . | . | . |
Amador | 10 | . | 4 | . | . | 6 | . |
Butte | 38 | 2 | 61 | . | . | 97 | . |
Calaveras | 6 | 1 | 1 | . | . | 7 | . |
Colusa | 6 | . | 4 | . | . | 1 | . |
Contra Costa | 42 | 15 | 5 | . | . | 13 | >. |
Del Norte | . | . | 6 | . | >. | . | >. |
El Dorado | 5 | . | 3 | . | >. | 18 | >. |
Fresno | 33 | 3 | 341 | 1 | >. | 412 | >7 |
Glenn | 15 | . | 21 | . | >. | 17 | >. |
Humboldt | 10 | . | 10 | . | . | 4 | . |
Imperial | 10 | . | 2 | 3 | >. | 10 | >2 |
Inyo | 13 | 3 | 4 | . | >. | 35 | >. |
Kern | 386 | 14 | 193 | 5 | >3 | 328 | >7 |
Kings | 37 | . | 2 | 3 | 1 | 13 | 1 |
Lake | 51 | 12 | 8 | . | . | 26 | . |
Lassen | 14 | . | 1 | . | >. | 27 | >. |
Los Angeles | 702 | 12 | 489 | 147 | >99 | 635 | >5 |
Madera | 12 | . | 30 | . | >. | 51 | >. |
Marin | 6 | . | . | 1 | >1 | 4 | >1 |
Mariposa | 6 | . | 2 | . | >. | 8 | >. |
Mendocino | 55 | 3 | 8 | 1 | >. | 12 | >. |
Merced | 27 | 1 | 73 | 2 | >2 | 88 | >. |
Modoc | 6 | . | 1 | . | >. | 10 | >. |
Mono | 4 | . | 1 | . | >. | 7 | >. |
Monterey | 90 | 1 | 135 | 10 | >7 | 146 | >. |
Napa | 28 | . | 1 | . | . | 24 | . |
Nevada | 9 | . | 8 | 1 | >1 | 21 | >. |
Orange | 188 | . | 5 | 37 | 7 | 170 | . |
Placer | 9 | . | 11 | . | >. | 20 | >. |
Plumas | 1 | . | . | . | >. | 16 | >. |
Riverside | 169 | 11 | 285 | 93 | >60 | 426 | >21 |
Sacramento | 82 | 1 | 300 | 12 | >6 | 309 | >. |
San Benito | 58 | 8 | 22 | 2 | >1 | 41 | >. |
San Bernardino | 232 | 7 | 454 | 93 | >60 | 706 | >53 |
San Diego | 74 | . | 5 | 6 | >1 | 110 | >2 |
San Francisco | 3 | . | . | . | >. | 1 | >. |
San Joaquin | 150 | 12 | 185 | 18 | >11 | 316 | >7 |
San Luis Obispo | 170 | 1 | 94 | . | >. | 227 | >2 |
San Mateo | 15 | . | 15 | . | >. | 18 | >. |
Santa Barbara | 138 | 1 | 40 | . | >. | 114 | >5 |
Santa Clara | 174 | 3 | 107* | 12 | >5 | 157 | >. |
Santa Cruz | 37 | 1 | 15 | . | >. | 19 | >. |
Shasta | 18 | 1 | 12 | . | >. | 99 | >. |
Sierra | . | . | . | . | >. | 9 | >. |
Siskiyou | 5 | . | . | . | >. | 19 | >1 |
Solano | 74 | . | 31 | . | >. | 73 | >. |
Sonoma | 156 | 8 | 30 | 2 | >1 | 99 | >. |
Stanislaus | 98 | 3 | 157 | . | >. | 231 | >10 |
Sutter | 18 | . | 21 | . | . | 16 | . |
Tehama | 6 | . | 42 | . | . | 28 | . |
Trinity | 1 | . | 1 | . | . | 4 | . |
Tulare | 27 | . | 130 | 11 | 7 | 249 | 18 |
Tuolumne | 3 | . | . | . | . | 10 | . |
Ventura | 150 | 5 | 11 | 2 | 2 | 71 | 4 |
Yolo | 81 | 23 | 54 | . | >. | 57 | >. |
Yuba | 8 | . | 9 | . | >. | 20 | >. |
TOTAL | 3,797 | 152 | 3,482 | 462 | >275 | 5,483 | >146 |
DLR (mg/L) | 0.1 | . | 0.001 | 0.004 | >. | .003 | >. |
NL (mg/L) | . | 1 | n/a** | . | >0.006 | . | >0.05 |
*Number of drinking water sources with at least one detection in water sampled 2000-2004. Numbers are considered "draft" because they will change with subsequent updates. **Chromium-6 has no NL. It is regulated under the total chromium MCL of 0.05 mg/L. Five sources had Cr-6 detected above 0.05 mg/L. |
On July 1, 2014, CDPH's Drinking Water Program transferred to the State Board to become the Division of Drinking Water.