GFI Atch 2 for Bidders Inquiry #8332507 Pages 3-4 Extracted from SAP for OBOD and Site 8.pdf

Sampling and Analysis Plan, OB/OD Unit and Site 8/Landfill 8 Tetra Tech

Contract No. FA3002-07-D-0016, TO 0015 September 2019 to purging with a tape or downhole electronic water level indicator. The indicator will be lowered into the water column only enough to obtain the water level and then will be withdrawn in order to limit suspending sediment that may be present in the bottom of the well. The measurement will be taken from the permanent, surveyed reference point on the well casing. The measurement will be to an accuracy of 0.01 foot and the measurement will be taken at least twice in succession to verify that precision is + 0.01 foot.

After all sampling is complete, the water level indicator will be lowered to the bottom of the well and a measurement will be taken from the surveyed reference point on the well casing. This measurement will be subtracted from the total well depth shown on the well completion log to determine if silting has occurred. The measurement will be repeated to verify precision of + 0.1 foot. All measuring devices should be thoroughly decontaminated before and after use.

2.2.2 Well Purging Methods

Low-flow (micropurge) techniques will be used to minimize mixing between the overlying stagnant casing water and water within the screened interval. The wells will be purged and sampled with a low-flow pump. Pumps should be held to a purge rate of 0.1 to 0.3 liters/minute, with a drawdown of 0.3 feet or less. Both dedicated and portable pumps will be used to purge the wells. The dedicated pumps will remain in their respective wells and thus do not require decontamination. For wells without dedicated pumps, portable pumps will be slowly lowered into the well to limit the mixing of water and the suspension of sediment that may be present in the bottom of the well. Portable pumps must be thoroughly decontaminated before and after use. One equipment blank will be collected using the portable pump at the end of each sampling period.

The pump intake will be located within the screened interval, at the approximate midpoint of the screen, unless previous information suggests otherwise, (e.g., significant sediment has accumulated in the bottom of the well). If possible, the pump should be kept at least 3.0 feet above accumulated sediment but well within the screened interval. The water level and pumping rate will be monitored throughout well purging. The pumping rate will be set to maintain a constant water level. If a constant water level cannot be maintained, the pump will be set at the minimum pumping rate. The well will be allowed to draw down at the lowest pump rate, but not allowed to draw down below the top of the screen, to allow the well to recharge. If, after two hours, the well has not shown sufficient recharge, the samples will be collected.

During well purging, field parameters will be recorded every 2 to 3 minutes until the parameters have stabilized. Parameters are considered stabilized when at least three consecutive measurements meet the following criteria: 1) DO ± 10% or < 1 mg/L; 2) pH ± 0.1 pH units; 3) Specific conductance ±

5%; 4) Turbidity < 10 NTU or as low as practicable given sampling conditions, and ± 10%; 5)

Temperature of all three readings are within 1-degree; and 6) Oxidation/reduction potential (redox) will be recorded but will not be used to determine stabilization. All purged water will be containerized.

All measurements and notes regarding well purging, including the estimated amount of water purged, will be included on the field information sheet.

2.2.3 Well Sampling

Monitor wells will be sampled by the low-flow sampling procedure using a dedicated or portable pump and uninterrupted flow stream that was used to purge the well. Samples will be taken before entering the in-line water quality monitor. Upon completion of well purging, the in-line water quality monitor will be disconnected or bypassed. Sampling flow rate must remain at the established purge rate or less when sampling. Flow rates less than 0.3 liters/minute are appropriate. Samples will be introduced into the sample containers directly from the pump tubing. Care will be taken to minimize turbulence and

Sampling and Analysis Plan, OB/OD Unit and Site 8/Landfill 8 Tetra Tech

Contract No. FA3002-07-D-0016, TO 0015 September 2019 introduction of entrapped air. The container will be filled and capped tightly. If the low-flow sampling procedure is not successful due to recharge rates of the monitoring well, another suitable means of sampling (e.g., disposable bailers) will be utilized.

As prescribed in CP Table IIIA, samples from the OB/OD Unit will be analyzed for anions, metals, nitroaromatics/nitramines, perchlorate, and volatile organic compounds (VOCs). Samples from Site 8 will be analyzed for anions, dehalococcoides, dissolved gases, metals, total organic carbon, and VOCs. All sample bottle labels will include the client name, sample ID, location, comments, preservative, collection date/time, name of the person who collected the sample, bottle type, and project number. Sample IDs will correspond to those listed in the Hazardous Waste Permit and Compliance Plan (CP) No. 50335, CP Table

V. The sampling and analytical requirements for the OB/OD Unit and Site 8 are prescribed by the laboratory for each analytical method and are listed in Tables 2-1 and 2-2 below. The laboratories selected to perform the analysis of the samples will be National Environmental Laboratory Accreditation

Conference (NELAC)-accredited through the Texas Laboratory Accreditation Program and will comply with the requirements of the Texas Commission on Environmental Quality (TCEQ) Regulatory Guidance

Review and Reporting of COC Concentration Data under TRRP (RG-366/TRRP-13).

Table 2-1

OB/OD Unit Sampling and Analytical Requirements

Method Group Analytical

Method Container Size

Preservation

Method Holding Time

Anions

2320B 1000 mL None 14 days

300_ORGFMS 1000 mL None 2 days

300_ORGFM_28D 1000 mL None 28 days

SM4500_S2_D 500 mL Zinc acetate and sodium hydroxide 7 days

Metals SW6020A 250 mL (2) Nitric Acid 180 days

SW7470A 250 mL (2) Nitric Acid 28 days

Nitroaromatics/

Nitramines SW8330A 500 mL (2) None 7 days

Perchlorate SW6860 125 mL None 28 days

VOCs SW8260B 40 mL (3) Hydrochloric Acid 14 days

Table 2-2

Site 8 Sampling and Analytical Requirements

Method Group Analytical

Method Container Size

Preservation

Method Holding Time

Anions SW9056A 125 mL (2) None 2 days/28 days

Dehalococcoides

Gene-Trac

Dehalococcoides

Assay 1000 mL None 7 days

Dissolved Gases RSK-175 40 mL (3) Hydrochloric Acid 14 days

Metals SW6020 250 mL Nitric Acid 180 days

Total Organic

Carbon SW9060A 40 mL (3) Sulfuric Acid 28 days

VOCs SW8260B 40 mL (3) Hydrochloric Acid 14 days