Closure Report for Cau 339: Area 12 Fleet Operations Steam Cleaning Discharge Area Nevada Test Site - Revision: 0

Page 1

Area 12 Fleet Operations Steam Cleaning Discharge Area Nevada Test Site Controlled Copy No. U.S. Department of Energy Nevada Operations Office j

Page 2

This report has been reproduced from the best available copy. DOE and DOE contractors can obtain copies of this report from the Office of Scientific and Technical Information, P.O. Box 62, Oak Ridge, TN 37831, (423) 576-8401. This report is available to the public from the National Technical Information Service, U. S. Department of Commerce, 5285 Port Royal Road, Springfield, VA, 22161, (703) 487-4650.

Page 3

This report was prepared as an account of work sponsored by an agency of the United States Government Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or use fulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any spe cific commercial product, process, or service by trade name, trademark, manufac turer, or otherwise does not necessarily constitute or imply its endorsement, recom mendation. or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the. United States Government or any agency thereof.

Page 4

Portions of this document may be illegible in electronic image products. Images are produced from the best available original

Page 5

CLOSURE REPORT FOR CAU 339: AREA 12 FLEET OPERATIONS NEVADA TEST SITE Prepared for the Nevada Operations Office Under Contract No. DE-AC08-96NV11718 Controlled Copy No.:

Page 6

CLOSURE REPORT FOR CAU 339: AREA 12 FLEET OPERATIONS STEAM CLEANING DISCHARGE AREA NEVADA TEST SITE Michael O. Giblin, Acting Project Manager Nevada Environmental Restoration Project

Page 7

TABLE OF CONTENTS Area 12 Fleet Ops ACRONYMS AND ABBREVIATIONS ............. v 1.3 Closure Report Contents..................................................... 4 2.1 Description of Corrective Action Activities ..................................................................... 6 2.2 Deviations From Corrective Action Plan ............................................................................8 2.3 Corrective Action Schedule as Completed ....................................................................... 8 4.1 Total Petroleum Hydrocarbon Results............................................................................. 12

Page 8

TABLE OF CONTENTS (continued) Area 12 Fleet Ops FIGURE 3 - CAU 339 CORRECTIVE ACTION BOUNDARY AND SAMPLE PLOT LOCATION ................... 7 TABLE 1 - AREA 12 DISCHARGE AREA SUMMARY OF TPH BASELINE SOIL SAMPLE TABLE 2 - AREA 12 DISCHARGE AREA SUMMARY OF BIO-CHARACTERIZATION BASELINE SOIL SAMPLE RESULTS................................................... 14

Page 9

Section: Act & Abb. Area 12 Fleet Ops ACRONYMS AND ABBREVIATIONS bgs below ground surface C:P Carbon to Phosphate CADD Corrective Action Decision Document CAP Corrective Action Plan CAS Corrective Action Site CAU Corrective Action Unit CEA Comparative Enumeration Assay COC Constituent(s) of Concern DOE U.S. Department of Energy ERD Environmental Restoration Division FFACO Federal Facility Agreement and Consent Order IRIS Integrated Risk Information System mg/kg milligrams per kilogram

Page 10

ACRONYMS AND ABBREVIATIONS (continued) Section: Acr & Abb. Area 12 Fleet Ops NAC Nevada Administrative Code NDEP Nevada Division of Environmental Protection NTS Nevada Test Site PRGs Preliminary Remediation Goals TPH Total Petroleum Hydrocarbon voc volatile organic compound WDNR Wisconsin Division of Natural Resources

Page 11

Section: Exec. Summary Area 12 Fleet Ops This Closure Report (CR) provides documentation of the completed corrective action at the Area 12 Fleet Operations site located in the southeast portion of the Area 12 Camp at the Nevada Test Site (NTS). Field work was performed in July 1997 as outlined in the Corrective Action Plan (CAP). The CAP was approved by the Nevada Division of Environmental Protection (NDEP) in June 1997. This site is identified in the Federal Facility Agreement and Consent Order (FFACO) as Corrective Action Site (CAS) Number 12-19-01 and is the only CAS in Corrective Action Unit (CAU) 339. The former Area 12 Fleet Operations Building 12-16 functioned as a maintenance facility for light- and heavy-duty vehicles from approximately 1965 to January 1993. Services performed at the site included steam-cleaning, tire service, and preventative maintenance on vehicles and equipment. Past activities impacted the former steam-cleaning discharge area with volatile organic compounds (VOCs) and total petroleum hydrocarbons (TPH) Closure activities at the former Area 12 steam-cleaning discharge area were completed in July 1997. Closure activities completed include excavating approximately 61 m3 (80 yd3) of hydrocarbon impacted soils, plugging the end of the discharge line, removing a sandbag berm constructed around the discharge line, regrading the site with imported Type II soils, and installing perimeter fencing. As part of the closure activity, soil samples were also collected from three undisturbed sample plots to establish a baseline for future post-closure monitoring and to verify that active biodegradation is occurring on the site. Samples were analyzed for TPH and bio-characterization parameters. Analytical results indicated that the sample points identified will be suitable to monitor the natural degradation of the remaining on-site hydrocarbons and that active . biodegradation is occurring. The post-closure monitoring program established for the site consists of sampling three selected sample plots on a biennial (every two years) basis. If after six years (three sampling episodes) the rate of degradation appears to be so slow that the greatest concentrations would not decay below 100 milligrams per kilogram (mg/kg) within 30 years, the site conditions will be re evaluated. Post-closure monitoring and sampling will begin in the spring of 1999, approximately two years from the completion of the site closure activities. Based upon the completion of the closure activities described within this document and the commitment for biennial post-closure monitoring of the former discharge area, it is requested that a Notice of Completion be provided by the NDEP and that CAU 339 be moved from Appendix III to Appendix IV in the FFACO.

Page 12

Area 12 Fleet Ops The Area 12 Fleet Operations site is located in the southeast portion of the Area 12 Camp at the Nevada Test Site (NTS) (Figure 1). The former Area 12 Fleet Operations Building 12-16 was constructed in approximately 1965 and functioned as a maintenance facility for light- and heavyduty vehicles up to January 1993. Services performed at the Fleet Operations site included steam-cleaning, tire service, and preventative maintenance on vehicles and special purpose A sand/oil interceptor, which segregated the materials generated from the steam-cleaning activities, is located at the southeast side of the Fleet Operations Building. Wastewater from the separator was gravity fed through a pipeline which discharged approximately 104 meters (m) (340 feet [ft]) east of the sand\oil interceptor into an open field. Physical boundaries of the discharge area include the Rainier Mesa Road to the south, a helicopter pad to the east, a natural erosional channel (arroyo) to the north, and a former parking area to the west. A soil berm separates the upper discharge area from a down gradient arroyo; however, discharge into the arroyo occurred prior to placement of the soil berm. Past activities impacted the discharge area with volatile organic compounds (VOCs) and total petroleum hydrocarbons (TPH) as oil. A site vicinity map is provided as Figure 2. Surface water appears to follow the natural topography which slopes predominantly to the east and northeast. Approximate Nevada coordinates for the site are N 890,000 and E 650,000 (from NTS Road and Facility Map, Holmes and Narver, 1986 update). This site is identified in the Federal Facility Agreement and Consent Order (FFACO) as Corrective Action Site (CAS) Number 12-19-01, and is the only CAS assigned to Corrective Action Unit (CAU) 339. This Closure Report (CR) provides documentation of the completed corrective action as outlined in the Corrective Action Plan (CAP) (DOE, 1997). The corrective action was completed in accordance with recently adopted Nevada Division of Environmental Protection (NDEP) closure 1997). In addition, the selected corrective action was supported by the evaluation of remedial alternatives outlined in the Corrective Action Decision Document (CADD) (DOE, 1996a). Detailed information of the site history and results of previous characterizations can be found in the Work Plan (REECo, 1992), the Preliminary Investigation Report (DOE, 1996b), and the Phase 2 Characterization Report which was provided with the CADD (DOE, 1996a). Previous characterization investigations were completed as a condition of the Temporary Water Pollution Control Permit issued by the NDEP to the Department of Energy (DOE) on July 14,1992

Page 15

Since the site was primarily closed in place, verification samples were not required. The selected remedial alternative for closure of the discharge area consisted of the following: • Excavating the hydrocarbon-impacted soils in the areas of visibly stressed vegetation and where hardened hydrocarbon layers had formed. • Removing the sandbag barrier surrounding the effluent line. • Plugging the end of the effluent discharge line. • Fencing and posting the area of hydrocarbon impact. • Biennial post-closure sampling and monitoring of the remaining hydrocarbon-impacted Using Preliminary Remediation Goals (PRGs) from the Integrated Risk Information System (IRIS) Database (EPA, 1996), removal of the VOC-impacted soils identified at the site was not required since the PRGs are well above maximum concentrations detected in the two previous site investigations (DOE, 1997). However, as a consequence of excavating the hydrocarbonimpacted areas, the majority of the VOC-impacted soils were removed. The closure activities and the post-closure monitoring only address the former release area east of the effluent discharge. Building 12-16, the former vehicle dispatch parking area, the sand/oil interceptor, and helicopter pad are not considered part of this closure as they are considered 1.3 CLOSURE REPORT CONTENTS This CR has been developed to sufficiently document the closure of the discharge effluent area. The format of the CR is: • Section 2.0 - Closure Activities (Description of Activities, Deviations from CAP, Completion Schedule, and Site Plan) • Section 4.0 - Analytical Results (baseline analytical results from biennial soil sampling) Area 12 Fleet Ops

Page 16

The corrective action was implemented using information and guidance provided from the • Corrective Action Plan for CAU No. 339: Area 12 Fleet Operations Steam-Cleaning Discharge Area Nevada Test Site (DOE. 1997T • Site Specific Health and Safety Plan for Area 12 Fleet Operations Steam-Cleaning Discharge Area Nevada Test Site Corrective Action Unit 339 fBN. 1997aV Discharge Area Nevada Test Site Corrective Action Unit 339 (DOE, 1996a). • Nevada Environmental Restoration Project. Project Management Plan (DOE, 1994). • Nevada Environmental Restoration Protect. Health and Safety Plan (DOE. 1996c). • Nevada Environmental Restoration Project. Industrial Sites. Quality Assurance Project Area 12 Fleet Ops

Page 17

' Section: Closure Activ. Area 12 Fleet Ops 2.1. DESCRIPTION OF CORRECTIVE ACTION ACTIVITIES Hydrocarbon-impacted soils were excavated using a front end loader to an approximate depth of 0.3 meters (m) (1.0 foot [ft]). The excavated areas were identified by the obvious stress to vegetation growth. Vegetation growth was inhibited in these areas by the hydrocarbon-impacted soils due to the development of a surficial hard layer of hydrocarbon crust. The majority of the excavation was completed in the vicinity of the effluent discharge line and the north eastern (lowest gradient point) area of the upper discharge area. Two locations within the arroyo were also excavated. The excavation areas are shown on Figure 3. Approximately 61 cubic meters (m3) (80 cubic yards [yd3]) of impacted soil was removed from the various portions of the upper discharge area and the arroyo. The sandbag barrier surrounding the discharge effluent line was also removed. The soil generated from the sandbag removal (approximately 23 m3 [30 yd3]) was used to backfill the areas excavated in the arroyo. The former effluent discharge line was plugged with Sulfaset cement. The plug was placed approximately 0.9 m (3 ft.) into the end of the 15 centimeter (cm) (6 inch [in]) diameter metal line and packed firmly to fill the void spaces in the line. Subsequent to excavation the upper discharge area was fenced using “T-Posts” with a double strand of plastic-coated cable wiring (Figure 3). The fence was installed to prevent unauthorized disturbance of the impacted soils, minimize the potential for an unauthorized release, and protect the sample areas identified for post-closure monitoring. Additional fencing was installed to identify the post-closure monitoring locations. Fencing was not installed in the arroyo (with exception of the post-closure sample plot) since access or disturbance to the area is unlikely. Signs were placed around the fence perimeter identifying the site as being impacted by petroleum hydrocarbons. Signs were also placed on the three post-closure sample plots identifying them as Sample Plots A, B, and C were not disturbed by excavation activities and consist of an approximate 1.5 m by 1.5 m (5 ft by 5 ft) area enclosed by T-Posts and a single strand of cable wire (Figure 3). Soil samples were collected from each plot and analyzed for a Comparative Enumeration Assay (CEA), Standard Nutrient Panel (SNP) and TPH as oil. The soil sample results will be used as a baseline to evaluate the natural degradation of the impacted soils remaining on-site (refer to Section 4.0 Closure Results).

Page 18

Sandbagged Area Removed Discharge Line Plugged (~3') and Cable Wiring Rainier Mesa Road Discolored Surface Soil Area & CAU 339 Boundary CAU 339 CORRECTIVE ACTION BOUNDARY AND SAMPLE PLOT LOCATION

Page 19

2.2 DEVIATIONS FROM CORRECTIVE ACTION PLAN Very few deviations from the CAP were required. A summary of the changes made during the progress of the site closure are as follows: • One CEA and SNP for bio-characterization analysis were collected from each sample plot instead of one composite sample from the three plots. Since variations in microbial activity are possible, better baseline controls will be realized by having a representative sample from • The size of each sample plot was extended from 1.2 m by 1.2 m (4 ft by 4 ft) to 1.5 m by 1.5 m (5 ft by 5 ft). The extended dimensions will allow for the collection of enough soil samples in the posted plot throughout the post-closure monitoring period. • Due to the shallow depth of gravel and rock, soil samples were collected from a depth range of 5 cm to 20 cm (2 in to 8 in) below ground surface (bgs). The CAP indicated that samples would be collected from 15 cm to 30 cm (6 in to 12 in) bgs. • The southern fence boundary extent was reduced since impacted soils did not extend laterally beyond the southern limit of the former sandbag berm. The northern boundary was tied into an existing fenced area to reduce the labor and materials needed to complete the northern perimeter boundary. The fence boundary is shown on Figure 3. • Decontamination of the front end loader was not warranted. Since soils were very dry, impacted soils were not affixed to the bucket or tires. In addition, backfilling with the imported Type II fill removed any soils which may have been remaining on the bucket or • Decontamination rinseate from the equipment was not placed into containers for disposal. The hand auger and soil sieves were washed with Alconox and water and rinsed with water over a stainless steel bowl. Due to the dryness of the soil, limited decontamination effort was required resulting in little residual. The residual generated evaporated quickly and in total amounted to no more than approximately 0.5 liters (16 ounces). Section: Closure Activ. Area 12 Fleet Ops 2.3 CORRECTIVE ACTION SCHEDULE AS COMPLETED The corrective action was completed …