I. BACKGROUND §5.1
II. SURFACE WATER RESULTS
A. Rainwater §5.2
Figure 5-1: Rainwater and Lake Sampling Locations
Figure 5-2: Rainwater Radiological Monitoring Results
B. Creeks §5.3
Figure 5-3: Creek Sampling Locations
Figure 5-4: Creek Tritium Monitoring Results
Figure 5-5: Annual Averages for Tritium in Chicken Creek (1994–1998)
C. Lakes §5.4
D. Hydraugers §5.5
Figure 5-6: Hydrauger Sampling Locations
Figure 5-7: Hydrauger Tritium Monitoring Results
E. Stormwater §5.6
Figure 5-8: Stormwater and Creekwater Baseline Sampling Locations
§5.1 I. BACKGROUND
Berkeley Lab’s surface water monitoring includes rainwater, creeks, lakes, hydraugers, and stormwater. The first four surface water types are monitored primarily for gross alpha, gross beta, and tritium, based on Department of Energy orders1 that prescribe monitoring for radioisotopes. Nonradiological sampling of surface water occurs as part of the Laboratory’s ongoing efforts to characterize and manage its overall impact on the environment. Stormwater monitoring is performed under the California General Permit for Stormwater Discharges Associated with Industrial Activities2 and includes monitoring for metals and other constituents. The monitoring programs for each type of surface water are further described in this chapter.
To place the Laboratory’s results into a familiar context, this chapter cites drinking water standards as a comparison for results from certain sampling programs. In actuality, the drinking water standard is not a compliance standard for the surface water program (no such standard exists), and the water being monitored is not a source of public drinking water.
Surface water samples were analyzed in 1998 by both commercial and in-house state-certified laboratories. Individual results can be found in volume II.
II. SURFACE WATER RESULTS
§5.2 A. Rainwater
Monthly rainwater composite samples are collected when rainfall occurs. In 1998, June, July, August, and September were dry months, so no samples were collected for those months.
Samples collected throughout the year came from three locations. See Figure 5-1. One location (ENV-75) is on site, near Building 75. Of the two off-site locations, one (ENV-B13C) is south of Berkeley Lab on Panoramic Hill, and one (ENV-B13D) is located northwest of the Lawrence Hall of Science.
Samples were analyzed for tritium and gross alpha and beta radiation. Figure 5-2 summarizes the levels of alpha, beta, and tritium seen in rainwater samples taken during 1998. Alpha and beta activity were either not detected or seen in low amounts at all stations, below federal and state maximum contaminant levels (MCLs) for drinking water: 0.6 Bq/L (15 pCi/L) for alpha and 1.9 Bq/L (50 pCi/L) for beta.3
Tritium was generally not detected in rainwater collected at off-site locations. On site, the maximum tritium level in rainwater was measured in the sample collected at ENV-75 in March (26.3 Bq/L). The mean tritium level for rainwater samples collected at ENV-75 was 11.8 Bq/L. For comparison, the maximum tritium level in rainwater represents approximately 3.5% of the US/EPA drinking water limit (740 Bq/L or 20,000 pCi/L).4
§5.3 B. Creeks
Given Berkeley Lab’s location in the hills of the Strawberry Creek watershed, many streams and creeks at and near the site flow at varying intensities throughout the course of the year. When creek flow occurs, a grab sample is collected and analyzed quarterly for alpha and beta activity and tritium. Creeks routinely sampled during 1998 were Chicken Creek, Claremont Creek, the North Fork of Strawberry Creek, Strawberry Creek (UC), and Wildcat Creek. See Figure 5-3 for locations.
A second set of creeks was also sampled and analyzed for tritium only. These creeks (also shown in Figure 5-3) include Botanical Garden Creek, Cafeteria Creek, No Name Creek, Ravine Creek, and Ten-Inch Creek.
No alpha or beta activity was detected at any sampling site, with the exception of very low amounts of both at Claremont Creek during the May sampling. Tritium was also generally not detected, except in Chicken Creek, where it was always seen at low levels. Measurable, though small, amounts of tritium were also found three times in the North Fork of Strawberry Creek and once in Wildcat Creek. A summary of tritium results above detection limits for creek sampling in 1998 is shown in Figure 5-4.
Chicken Creek is the only creek in which tritium has been found with any regularity. Figure 5-5 presents a comparison of the annual mean for tritium over the last five years in Chicken Creek. From a high of 43.9 Bq/L (1,190 pCi/L) in 1995, levels dropped by nearly half in 1996 to 23 Bq/L (620 pCi/L) and have remained reasonably consistent since then.
One sample was collected during the year from the second set of creek sites and analyzed for tritium and nonradiological parameters (volatile organic compounds (VOCs), hardness, and metals). The North Fork of Strawberry was also sampled a second time for VOCs, semivolatiles, tritium, and metals. All semivolatiles and VOCs were below detectable levels, except for one measurement for diethylphthalate in the North Fork of Strawberry Creek. A repeat sampling of semivolatiles also showed this to be below detectable levels. No tritium was detected in any of the creeks sampled in this set. Trace levels of barium, chromium, copper, lead, molybdenum, selenium, vanadium, and zinc were found. These levels were consistent with past results and with natural background levels.
§5.4 C. Lakes
Lake sampling is performed once each year at Lake Anza in Tilden Regional Park and at Lake Temescal in Oakland’s Temescal Regional Park. See Figure 5-1. For 1998, no samples from either lake contained alpha or beta activity or tritium above minimum detectable amounts.
§5.5 D. Hydraugers
Because of its steep hillsides, Berkeley Lab uses hydraugers to manage soil stability. Hydraugers are perforated pipes inserted into a hillside to improve drainage of groundwater. Figure 5-6 shows the locations of monitored hydraugers. In 1998, the frequency of hydrauger monitoring was reduced from quarterly to semi-annually. Summary tritium data for hydraugers are displayed in Figure 5-7.
Five hydrauger sites (HYG77-0101, HYG77-0104, HYG77-02XX, HYGCC1, and HYGCC2) were routinely monitored in 1998 for alpha, beta, and tritium. HYG77-0103 has been deleted from the program because of lack of flow. HYG77-02XX is a manifold of several hydraugers (HYG77-0204 through HYG77-0207) and is sampled at the common discharge point. Hydraugers prefixed with HYG77 are located behind Building 77, while those prefixed with HYGCC are located near Chicken Creek, further to the south and further down the hillside.
Because hydrauger flow depends on several factors (including rainfall), it can vary considerably. No flow or very low flow prevents samples from being taken. For example, HYG77-0104 was dry in all four quarters during 1998, and no samples could be taken from it.
At the hydraugers that could be sampled, alpha and beta were always below detection limits. Tritium levels varied considerably. Tritium was detected in 73% and 33% of the samples collected from the HYG77 and HYGCC hydraugers, respectively. The highest level measured was 504 Bq/L for a sample collected at HYG77-0101 on January 20.
§5.6 E. Stormwater
Berkeley Lab lies within the Blackberry Canyon and Strawberry Canyon watersheds. There are two main creeks in the watershed, Strawberry Creek and the North Fork of Strawberry Creek, plus several small tributaries that generally do not flow all year long. See Figure 5-8.
Surface runoff from Berkeley Lab is substantial because of the site’s hillside location, the amount of paved or covered surface, and the moderate annual rainfall. All stormwater runoff from the site drains through this system to Strawberry Creek or its north fork, which join below the Laboratory on the UC Berkeley campus.
Under the State of California’s National Pollutant Discharge Elimination System (NPDES) program, Berkeley Lab must follow the General Permit for Stormwater Discharges Associated with Industrial Activities.5 Permit holders must develop and maintain a Storm Water Monitoring Plan (SWMP)6 and a Storm Water Pollution Prevention Plan (SWPPP).7 These are the guiding documents for the Laboratory’s compliance with stormwater regulations. For further discussion of this compliance program, see §§3.24, 3.25, and 3.26.
Berkeley Lab’s SWMP explains the rationale for sampling, sampling locations, and the kinds of radiological and nonradiological analyses to be performed. For metals, the permit requires analysis for total metals. Following a request from the City of Berkeley, however, Berkeley Lab has committed to analyzing at least one sample per stormwater year for both total and dissolved metals as a comparison. Dissolved metals are consistently lower than total metals. Sampling points are shown in Figure 5-8.
Two of the monitoring points, StW01 and StW03, are influent points, where stormwater comes onto the site from residential areas, roads, and UC Berkeley campus facilities located above Berkeley Lab. These points were chosen as a basis of comparison and to aid in an investigation if contaminants are found.
Under the terms of the general permit, sampling must take place at least twice each "stormwater year" (July 1 through June 30) under specific conditions. Monitoring also includes visual observation of one storm per month and quarterly observation of authorized and unauthorized nonstormwater discharges. All sampling points must be monitored for the following:
Note that in calendar year 1998, stormwater monitoring was performed only once because of rainfall patterns during the 19981999 stormwater year.
In 1998, pH was always near neutral, and total petroleum hydrocarbons (diesel) and oil and grease (both tests for gas or oil) were once detected in very low quantities in Chicken Creek and B69 Storm Drain (StW03), its influent point. Interestingly, levels decreased between the influent and effluent points, indicating that the site may actually be retaining contaminants. Specific conductance, usually a measure of the degree of mineralization of water, was low and within the range of domestic drinking water. The measure for total suspended solids (TSS) was also usually quite low, indicating clear water. B69 Storm Drain was an exception; it had a relatively higher number for TSS in the influent point. Chemical oxygen demand, filtered (CODF), is a measure that can be correlated to the amount of organic matter in the water. CODF results in stormwater discharge for the Laboratory were generally low.
Metals results were generally in the "nondetect" range. Only aluminum, iron, and manganese were occasionally seen at low levels in the total metals analyses. The general permit does not contain specific discharge limits for metals. For comparison purposes, Table 4-3 of the Basin Plan8 gives effluent limitations for selected toxic pollutants discharged to shallow surface waters applicable to point source discharges from Publicly Owned Treatment Works (like the East Bay Municipal Utility District) and industrial effluent.
Routine stormwater samples are also analyzed for alpha and beta emitters and tritium. Neither alpha nor beta emitters were detected. All tritium values were low, ranging from 8.7 Bq/L (235 pCi/L) at East Canyon (StW05) to 65.2 Bq/L (1,760 pCi/L) at Building 69 Influent (StW03). The influent point at Building 69 consistently has the highest values for tritium in stormwater. The tritium value for the corresponding effluent point, Chicken Creek or StW04, is about half that level at 35.1 Bq/L (948 pCi/L).
During 1998, Berkeley Lab completed the special creek water baseline project, which was initiated in 1997 and described in last year’s Site Environmental Report. The goal of this internal project was to establish a baseline for the quality of creek water being discharged from the site. The last phase of the project occurred in 1998, concomitant with the second stormwater sampling for the 19971998 season.
As with the first and second sampling rounds, samples were taken from the North Fork of Strawberry Creek, Strawberry Creek at the Botanical Garden, Chicken Creek, and B71 Storm Drain, an influent point. In addition, B69 Storm Drain, the Water Tower on the North Fork of Strawberry (both influent points), and East Canyon were also sampled. See Figure 5-8. Analyses were run for the following:
Results in general are the same as the stormwater results described above. For the two additional monitoring locations, NFS influent at Water Tower and Strawberry Creek at Botanical Garden, no oil and grease, TPH diesel, or gross alpha or tritium were detected. At the Water Tower, beta activity was only slightly above the detection limit. CODF and TSS were within normal ranges, as were pH and specific conductance. Aluminum, barium, copper, iron, magnesium, manganese, and zinc were generally detected at low levels. Traces of nitrate and ammonia as nitrogen were detected in both locations. A normal range of constituents and levels was found in the general minerals analysis.