Return to Table of Contents
| Quick Scroll To |
| Background |
| Wastewater Discharge Program |
| Hearst and Strawberry Sewer Outfalls |
| Building 25 Photofabrication Shop |
| Building 77 Fixed Treatment Unit |
| Treated Hydrauger Discharge |
Sanitary sewer discharge monitoring is divided into two major types: regulatory-based and DOE-based. Regulatory-based monitoring is generally termed self-monitoring, and is mandated in the wastewater discharge permits1 granted to Berkeley Lab by the East Bay Municipal Utility District (EBMUD). Samples are analyzed for pH, total suspended solids, and chemical oxygen demand, with additional analyses for volatile organic compounds and metals included required in specific permit situations. Analysis is performed by a state-certified outside contract laboratory. Results are compared against the discharge limits for each parameter given in the permits, and self-monitoring reports are submitted to EBMUD.
DOE-based monitoring concentrates on radiological parameters. This type of monitoring is required by DOE guidance2 and orders,3 but also ensures compliance with the radiological limits given in the California Code of Regulations.4 California regulations now incorporate by reference the applicable federal regulations,5 thus making the California limits for discharge the same as the federal limits. Sanitary sewers are normally monitored for gross alpha, gross beta, iodine-125, and tritium. Gross alpha and gross beta measurements are used as a screening mechanism to determine if specific radionuclide measurements are required. Currently such monitoring is performed biweekly, and split samples are analyzed by both an outside laboratory and Berkeley Lab's in-house Radiation and Analytical Measurement Laboratory as a quality control measure.
Sanitary sewer discharge is monitored at two site outfalls, Hearst and Strawberry (see Figure 2-5 in Chapter 2 for locations). These two locations capture all wastewater leaving the site, although the discharge from Strawberry Sewer includes effluent from certain UCB facilities in Strawberry Canyon located both above and below the Berkeley Lab site. Additional details of the sewage system are given in the Sanitary Sewer Systems section of Chapter 2, Introduction. Self-monitoring of wastewater discharge within Berkeley Lab also occurs at Buildings 25 and 77, and at groundwater treatment units, according to the terms of their respective EBMUD permits.
Berkeley Lab currently has four wastewater discharge permits issued by EBMUD: one for general sitewide discharges, two for the metal finishing facilities found in Building 25 and Building 77, and one for the discharge of treated groundwater from hydraugers. EBMUD annually renews the site's wastewater discharge permits in September.
As the local Publicly Owned Treatment Works, EBMUD regulates all industrial discharges to its treatment facilities. The self-monitoring dates for 1996 identified by EBMUD for each Berkeley Lab permit are presented in Table 7-1. In addition, EBMUD has discretion to conduct its own monitoring at the site. Table 7-2 lists the dates and locations of these unannounced inspections by EBMUD.
Berkeley Lab's wastewater management program has an outstanding record. As a measure of the effectiveness, the Laboratory has not had any violations of its wastewater discharge permits for either technical reasons or exceedance of wastewater discharge limits since September of 1994. Operational changes in metals finishing and implementation of programs designed to reduce pollutant discharges have contributed significantly to this record.
Effective program management has also given Berkeley Lab flexibility to start several new undertakings in 1996 that reduce the amount and cost of low-level radioactive or hazardous waste disposed to offsite facilities. In one effort, materials classified as waste only for their short-lived radiological isotope content are allowed to decay in place until they have reached insignificant levels and can be safely and legally disposed of to the sanitary sewer. This disposal activity takes place only at the HWHF. Another effort involved testing of water from the "water curtain" used in a paint spray booth to control atmospheric emissions to determine the level of hazardous constituents in the water. Results of the testing made it possible to dispose of this water to the sanitary sewer in compliance with discharge limits.
Yet another program enables selected researchers using short-lived radioactive isotopes in their laboratories to dispose of nonhazardous liquid wastes to the sanitary sewers. Eligible research programs are selected on the following basis:
Once selected, these research programs follow stringent sampling and characterization conditions.
Many of the requirements that EBMUD had mandated for Berkeley Lab in past years have been relaxed because of the Laboratory's outstanding ongoing compliance record. For example, EBMUD no longer requires calibration reports on the various equipment, such as flowmeters, that the Laboratory still calibrates. Similarly, the semi-annual flowmeter reading reports are no longer requested by EBMUD. Annual flow information is still gathered biweekly and provided to EBMUD as part of the annual renewal of the discharge permits.
Hearst and Strawberry Sewer Outfalls
Nonradiological
A major improvement in sanitary sewer monitoring occurred in 1996, when the Hearst monitoring station was connected to the Laboratory's communications network system. This connection allowed real-time remote viewing of station flowmeter information, giving monitoring personnel better control over the tracking of flow, and a quicker response in the event of instrumentation failure. Flowmeters provide vital information used to determine both wastewater charges from EBMUD and the accuracy of radiological sampling reports. The difficult terrain and the monitoring station's distance from telephone lines make a similar connection of the Strawberry outfall to telemetry service not feasible at this time. However, the Laboratory currently uses redundant flowmeters to collect reliable backup information.
Six self-monitoring samples were taken from the Hearst and Strawberry outfalls during 1996. All results were well within discharge limits, as were all measurements made by EBMUD in its independent samplings. Analyses for metals were required for only the second and fourth sampling events. Table 7-3 illustrates the average annual levels of metals found in these two samples. Permit discharge limits are given for comparison.
Radiological
Hearst and Strawberry sewer outfalls are sampled continuously by automatic samplers that collect samples at half-hour intervals at Hearst and 20-minute intervals at Strawberry. The composite samples are collected biweekly by technicians. Analysis for iodine-125, gross alpha, gross beta, and tritium is performed by both the in-house laboratory and a state-certified outside laboratory. Some split samples were occasionally analyzed by a third laboratory for additional quality control purposes.
Regulatory guidelines used to evaluate radioactive sewer discharge data are not concentrations, as they are with surface water. Rather, the federal6 and state7 regulatory limits are total amounts per year. For tritium, this amount is 1.85 x 1011 Bq (5 curies) per year; for carbon-14, the limit is 3.7 x 1010 Bq (1 curie) per year; and the limit for all other radioisotopes is a total of 3.7 x 1010 Bq (1 curie) per year.
Radioanalyses of Berkeley Lab's sewer wastewater for 1996 are summarized in Table 7-4. Tritium was often less than the minimum detectable activity. The total discharge of tritium in wastewater was 6.68 x 109 Bq (0.18 Ci), and the total for other radioisotopes was 7.02 x 108 Bq (0.019 Ci). Both measures are down significantly from 1995 when the corresponding discharges were 4.81 x 1010 Bq (1.3 Ci), and 5.93 x 109 Bq (0.16 Ci), respectively These values are well below allowable limits. Tritium, for example, was only 4% of the allowable limit. When present, tritium was found in greater concentrations at Strawberry than Hearst. Alpha, which comes from transuranic and heavy element research, was generally nondetectable at both sewers. Beta, including iodine-125 from biomedical research, was consistently low in both sewers.
The source of tritium discharged from the NTLF is wash water. This wash water is strictly monitored. It is discharged only if analysis is below 7.4 x 107 Bq (2,000 µCi) per day. This threshold level is an LBNL-imposed administrative limit of 10% of the strictest regulatory limit mentioned above.
Building 25 Photo Fabrication Shop
The Photofabrication Shop in Building 25 manufactures electronic printed wiring boards and screen print nomenclature on panels as needed to support Berkeley Lab research and operations. Wastewaters containing metals and other hazardous materials from these operations are routed to a fixed treatment unit (FTU) prior to discharge to the sanitary sewer. The Building 25 FTU has successfully operated in batch mode since an upgrade in 1993.
In March of 1996, a reverse osmosis and ion exchange system for this unit came on line. This addition is a closed-loop recycling system that will reduce FTU wastewater volume between 50% and 90% per month. The system allows reuse of rinsewater and reduces contaminant loading, primarily copper, on the treatment unit.
In July, the Photo Fabrication Shop stopped general operations for facility improvements. During the upgrade, the shop was limited to small chemical milling and screening processes. Taking advantage of the reduced operations, the flowmeter required by EBMUD was repositioned to allow future calibrations to occur without removing the meter.
By December, the shop was gradually brought back on line. The two self-monitoring samples from this FTU for the year were taken despite the upgrade project. None of the sample analyses exceeded discharge limits set by EBMUD.8 All sampling performed by EBMUD also yielded results well within discharge limits.
Building 77 Fixed Treatment Unit
The Ultra High Vacuum Cleaning Facility (UHVCF) at Building 77 cleans metal parts that are used in research and support operations at Berkeley Lab. The cleaning process selected depends on the type of metal to be cleaning. Cleaning operations available include passivating, UHV cleaning, and vapor degreasing. Acid and caustic rinsewaters from these operations are routed to a nearby fixed treatment unit.
During 1996, the UHVCF completed several major changes. This facility reopened in March after undergoing a complete rebuilding. A temporary cleaning facility in adjacent Building 77H meet Berkeley Lab's interim cleaning demands.
During the upgrade project, a new 227-liter-per-minute (60-gallon per minute) FTU was installed. This unit can treat acidic rinsewaters containing metals and alkaline rinsewaters generated by the UHVCF. As part of EBMUD's approval of a permit modification for this unit, pilot testing following EBMUD procedures began in May. The unit functioned at full capacity during which time the effluent was sampled once per day for five consecutive days and analyzed for the same constituents required by the permit. All results were well below the discharge limits for each respective parameter.
As part of the approved permit, the old 57-liter per minute (15-gpm) treatment unit was left online to serve as a backup. The old unit has not operated since startup of the new unit.
In April, before the pilot testing, deionization units for rinsewaters at Building 77 were installed. They are expected to save 132 liters (35 gallons) per minute of waste from entering the treatment unit.
Four self-monitoring samples were taken from the Building 77 FTU during 1996. None of the sample analyses, nor any sampling done by EBMUD, exceeded any of the discharge limits in the permit.9
Since the latter half of 1993, Berkeley Lab has had permission from EBMUD to discharge treated groundwater (groundwater that had been contaminated with volatile organic compounds and tritium) to the sanitary sewer. The treatment process consists of passing the contaminated groundwater through a double-filtered carbon adsorption system. In 1996, EBMUD decided that this activity warranted a separate permit. Berkeley Lab received this new permit in September, initially for discharging treated groundwater from the Building 51 hydrauger system and Building 51 Fire Trail. Berkeley Lab later applied for a revision to add three areas to this permit:
EBMUD approved the request effective in late December 1996. One of the conditions for this discharge was a report on the volumes discharged and any contaminants found.
Similar groundwater treatment activity also occurs at Building 37, but the treated water is reused in cooling towers onsite and therefore does not need a permit from EBMUD.
Tests using US/EPA methodologies are run quarterly on treated groundwater to determine levels of volatile organic compounds. In general, all results have been nondetect. Occasional detections of certain chlorinated hydrocarbons have been extremely low (parts per billion) and do not exceed allowable limits. As a precautionary measure not required by the permit, a sample is taken from between the two drums of carbon in each system to assist in determining when the first drum should be changed out. This prevents contaminated groundwater from being discharged to the sanitary sewer. Chapter 6, Groundwater Protection, contains further details on groundwater monitoring and treatment.
| Return to Top of Page |
| Return to Table of Contents |
