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3. The Annual Monitoring Report as a primary document requires responses to comments, but in last year's report (2000 Annual Monitoring Report), the responses to regulatory comments were not included in the Final version. Please include a table of regulatory comments and responses in the Final version of the 2001 Report. SPECIFIC COMMENTS 1. Section 4.2.4.2, Page 4-3: The Report states that phthalates were detected in five wells during the 2001 sampling event (Solid Waste Management Unit [SWMU] 2, SWMU 3, SWMU 7, SWMU 8, and SWMU 20), but the last sentence of this section implies that the detections were due to laboratory contamination. While phthalates may be attributable to laboratory or field contamination at some sites, they are common contaminants at disposal sites (landfills, bum pits), and the Record of Decision (ROD) for the Tracy site set soil cleanup standards for the burn pits at Solid Waste Management Unit (SWMU) 7 and SWMU 8, and the sewage lagoon at SWMU 2. In addition, the ROD set 10 ug/L as a Groundwater Concentration Requiring Evaluation for bis(2-ethylhexyl) phthalate (DEHP) at SWMU 7, SWMU 8, SWMU 2, and SWMU 3. DEHP was reported as high as 53 ug/L at SWMU 7, well above the ROD-specified concentration. Please replace the statement about common laboratory contaminants with a statement naming the SWMUs as the likely source of phthalates. 2. Table 4.1-2, Page 4-15: The table presents only primary MCLS and implies that no secondary MCLS have been established for the listed chemicals. Many of the metals such as iron and zinc have secondary MCLS. Please revise the footnote to define MCL as the primary maximum contaminant level. 3. Table 4.1-2, Page 4-15: The table lists the MCL for arsenic as 0.050 milligrams per liter (mg/L). On October 31, 2001, EPA decided to implement a revised MCL for arsenic of 0.010 mg/L. Although arsenic is not a chemical of potential concern in groundwater at the Tracy site, the water quality standard used for comparison of monitoring results should be the latest MCL. Please revise the MCL for arsenic to 0.010 mg/L. 4. Table 4.1-2, Page 4-15: The table lists the MCL for lead as not established. As we pointed out on last year's report, lead has an established MCL of 0.015 mg/L. Please revise the table to include the lead MCL of 0.015 mg/L. This comment also affects Table 4.1-3. 5. Section 7.3.2, Page 7-2: The text recommends evaluation of air-to-water ratios in the GWTP2 air strippers, using the same wording as last year's report (Section 6.3.1, page 6-2). However, Table 5.2-1 indicates that the air flow problem at GWTP2 was addressed in November 2001. Please revise this section in the next version of the Report to discuss the results of the repairs made at GWTP2. In particular, present an evaluation of whether 2