EA-Environmental Consequences

FRC research activities would not change the landscape (e.g., large-area bulldozing, large-scale clearing, and excavation.) Activities to support site characterization, to obtain research-quality samples, and in situ research would not impact the general topography of the proposed FRC because of the small-scale nature(less than one acre) of the proposed activities.

4.2.1.2 Geology

The 100-H area in which the proposed contaminated area and background area are located is dominated by the Hanford and Ringold formations, which contain primarily sand and gravel dominated facies. Because of the small-scale nature of investigations (less than one acre and to a depth of up to 75 feet), minimal impacts to these large geologic units are anticipated as a result of proposed FRC activities.

Within the 100-H Area, soils are classified as either Burbank loamy sand or Riverwash, with Riverwash occurring closer to the river. Proposed FRC activities would disturb these soil types only in areas where drilling, boring, or well installation would occur. Uncontaminated soils would be redistributed around the test plot. Contaminated soils would be disposed of in accordance with site-specific management plans. Soils obtained as research-quality samples would be characterized for potential hazardous contaminants prior to laboratory experimentation. It is estimated that the quantity of soil removed as a result of research activities at a test plot would be small (75 kilograms of soil per well or 825 kilograms of soil from 11 wells in a test bed); therefore, impacts to soils would be minimal.

Climate at the Hanford Site is classified as mid-latitude semiarid or mid-latitude desert, depending on the climatological classification scheme used. Summers are warm and dry with abundant sunshine. Large diurnal temperature variations result from intense solar heating during the day and radiational cooling at night. Daytime temperatures in June, July, and August periodically exceed 100°F (38C). Winters are cool with occasional precipitation. Outbreaks of cold air associated with modified arctic air masses can reach the area and cause temperatures to drop below 0°F (-18C). Overcast skies and fog occur periodically.

Air quality in the Hanford region is well within the state and federal standards for criteria pollutants, except that short-term particulate concentrations occasionally exceed the 24-hour "particulate matter nominally 10 microns or less" (PM₁₀) standard. Benton County is in an "unclassified" area for PM₁₀ (Neitzel et al. 1999).

Surface waters within the 100-H Area are dominated by the Columbia River, which flows alongside the contaminated area of the proposed FRC (see Figure 3-9). The two background areas are located approximately one-half mile from the Columbia River. FRC activities to support site characterization, obtain research-quality samples, and perform in situ research would not occur any closer than 200 feet (60 meters) from all surface waters, including the Columbia River. Any potential runoff occurring as a result of ground-disturbing activities, coupled with rain events, would be reduced by implementing best management practices (e.g., silt fences).

The closest point where injection of materials might occur would be in the contaminated area 200 feet from the Columbia River. While it is conceivable that injected materials could reach the Columbia River if an injection well were installed at this point, PNNL anticipated the need to recover injected substances. PNNL proposed that they would install a series of groundwater extraction wells within each test plot to capture any substances injected into upstream injection wells. These extraction wells would be positioned to intercept groundwater flow moving toward the Columbia River. In addition, PNNL could make use of a secondary containment system of five existing extraction wells located within 150 feet of the Columbia River to ensure that substances injected as part of in situ research by investigators do not reach the Columbia River. The existing five extraction wells are part of an on-going CERCLA Interim Remedial Action that involves pumping and treating for chromium-contaminated groundwater. Filters to extract tracers, electron donors and acceptors, nutrients, microorganisms and other substances would be added to the extraction well systems. The pump and treat extraction wells have been operating constantly and will continue to do so (DOE/RL 1999c).

All contaminated water extracted from the proposed wells and existing pump and treat extraction wells would be collected in large truck-mounted tanks and transported to the Effluent Treatment Facility (ETF). Contaminated water extracted from the existing pump and treat extraction wells goes through a filtration system and is reinjected into the ground upstream from the pump and treat area. (See Section 4.2.10 for waste control information.) In the unlikely event that all of the existing and proposed extraction wells failed, the potential exists that groundwater additives injected as part of in situ research at either the background or contaminated areas could pass through groundwater channels in the highly porous loamy sand soils of the 100-H Area to the Columbia River.

As described in Appendix A, small quantities of nontoxic tracers, nutrients, electron donors or acceptors, microorganisms, or other substances might be injected as part of the in situ research activities. These substances might be injected either into the background or contaminated areas of the proposed FRC in accordance with state and federal regulations, best management practices and close monitoring of environmental conditions. While in situ research at the background and contaminated areas would provide additional information on groundwater flow paths and the movement of injected materials, sufficient information currently exists to permit estimates of potential impacts from the injection of these materials on surface waters.

To better understand groundwater flow paths and speed, nontoxic and nonpersistent tracers could be injected in concentrations ranging from 500 parts per million (ppm) to 10,000 ppm at both the background and contaminated areas of the proposed FRC. Examples of tracers that might be used include bromide, chlorofluorocarbons, latex microspheres, alcohols, and non-radioactive strontium. Tracer injections at the two proposed background areas would be more than 1,500 feet from the Columbia River and concentrations would be expected to be unmeasurable by the time the tracer had traveled only half that distance. In part, this would be due to a slow groundwater flow rate of six inches per day and to the diffusion of the tracer into the subsurface matrix. In contrast, tracer injections into the contaminated area, particularly into test plots C and D, which are close to the Columbia River, could conceivably reach the surface waters if they were not captured by proposed NABIR extraction wells or existing pump and treat extraction wells.

As with tracers proposed for use at the ORNL FRC, tracers proposed for use at the background and contaminated areas of 100-H would also be greatly diluted by diffusion into the matrix of the 100-H Area subsurface. Assuming that no NABIR extraction wells were installed, injected tracers would be recovered in the continuously operating pump and treat extraction well systems.

Different tracers move and diffuse into the groundwater at different rates. Therefore, the use of more than one tracer at the same time provides additional information about the subsurface than would be possible with only one tracer. Injection of multiple tracers at one time in the contaminated area in an injection well 200 feet from the Columbia River would not be expected to result in an increased possibility that any of the tracers would reach the Columbia River. Again, both the proposed NABIR extraction well system and the existing pump and treat system would be employed to ensure that these tracers would not reach the Columbia River.

Tracer concentrations would not be expected to exceed 10,000 ppm. The use of nontoxic and non-persistent tracers coupled with the proposed and existing extraction well systems would ensure that tracers would not reach the Columbia River. Further information on the proposed use of groundwater tracers at the FRC is available in Appendix A.

To stimulate the activity and growth of microorganisms, electron donors or acceptors or other nutrients could be injected in concentrations ranging from 100 ppm to 300 ppm (i.e., 100 mg/L to 300 mg/L) at both the background and contaminated areas of the proposed FRC. At maximum, these concentrations would be lower than those that would be considered at the ORNL FRC. Examples of electron donors that might be used include acetate, glucose, lactate, hydrogen, or molasses. Examples of electron acceptors that might be used include oxygen, nitrate, methane or sulfate. Other nutrients might include nitrogen and phosphorus. Injections at the background area would not occur in close proximity to the Columbia River (i.e., they would be more than 1,500 feet from the Columbia River).

Although injections at the contaminated area could be as close as 200 feet to the Columbia River, the likely approach for such injections would be a push-pull approach. In a push-pull experiment, electron donors, acceptors or nutrients would be "pushed" into a single injection well, and then "pulled" out of the same well after a short time of up to several hours (Schroth et al. 1998). Using this type of injection/extraction procedure in a single well, PNNL estimates that approximately 95 percent of the injected materials could be recovered through the injection well (Long 1999a).

In some cases, electron donors, electron acceptors, or nutrients could be injected into one well and extracted from another. In such a situation, the proposed series of NABIR extraction wells and the existing pump and treat extraction wells would mitigate any potential for electron donors, electron acceptors, or nutrients to reach the surface waters of the Columbia River. In addition, the proposed NABIR extraction wells and the existing pump and treat system would capture any contaminants that might be mobilized as a result of the addition of electron donors, electron acceptors, or nutrients in the contaminated area.

Another point to consider would be a shift in the existing microbial population due to the addition of electron donors, electron acceptors, or nutrients. Based on two other recent studies, even though the species that constitute the existing microbial populations might shift, the shift would only be detectable as long as the electron donor, electron acceptor or nutrient was present in the groundwater (Konopka et al. 1999, Rooney-Varga et al. 1999). Once the electron donor, acceptor or nutrient was removed from the groundwater through the extraction well systems, the microbial populations would return to their previous state, and there would be no change to inputs to the Columbia River.

Further information on the proposed use of electron donors and acceptors and nutrients at the FRC is available in Appendix A.

To determine whether it might be feasible to add microorganisms to a contaminated subsurface environment, a small quantity (2 X 10⁷ colony forming units per ml [cfu/ml]) of native microorganisms could be injected into the background and contaminated areas of the proposed FRC. Native microorganisms would most likely be strains that would be isolated from the contaminated area and reinjected. Reinjection of native microorganisms would not be expected to be of concern either at the background or contaminated area. Although they would not be expected to move through the groundwater (Dybas et al. 1997), it is conceivable that they could proliferate. In some cases, the push-pull technique might be used; in other cases, one injection and one or more different extraction wells might be used. In either situation, the microorganisms would be captured in the proposed NABIR extraction wells or in the existing pump and treat extraction wells.

PNNL has stated that non-native microorganisms would be those from a non-Hanford field site (Long 1999b). Non-native microorganisms would not be injected either at the background or contaminated areas. Similarly, genetically engineered microorganisms would not be used either at the background or contaminated areas. Further information on the proposed use of microorganisms at the FRC is available in Appendix A.

As discussed in section 4.1.3.1.4, the two primary classes of other substances that might be injected would be biosurfactants and chelators. However, unlike the proposed ORNL FRC, PNNL would not consider using these two classes of substances either at the background or the contaminated areas. Because they would not be used, there would be no impacts to the surface waters of the Columbia River.

The only proposed FRC activities expected to occur within floodplain areas would be well drilling and monitoring (e.g., installation of piezometers). Typical installations of wells or piezometers, using for example, 2 foot by 6 inch (0.41 meter by 15.24 centimeter) diameter protective casing and 4 foot by 3 inch (0.82 meter by 7.62 centimeter) diameter bollards with a concrete pad 3 inches high and 2 feet long (7.62 centimeters by .41 meters) may reduce the cross-sectional area of the floodplain by 1.64 square feet (.5 square meters). This reduction in volume of even several wells would be negligible within the total cross-sectional area of the floodplain. Well and piezometer construction therefore, would have negligible impact on the floodplain. The well pads would minimize the erosion potential of the wells and bollards.

At the appropriate time, wells would be plugged (backfilled with clean soils) and abandoned. Well plugging and abandonment would result in the removal of surface structures (e.g. wellheads) and restoration of the former grade. This activity would have little impact on floodstage or floodplain cross-sectional area, nor would there be an increase in erosional potential since the wellhead and other surface equipment would be removed and the site restored to the original grade.

No structures or facilities would be constructed in the floodplain. Movement of heavy equipment through the floodplain would be a temporary occurrence and would not impact the capacity of the floodplain to store or carry water. The impacts from the movement of heavy equipment alone is expected to be negligible. To the extent practicable, staging areas and access roads would be temporary, construction would be limited to periods of low precipitation, and stabilization and restoration of the affected areas would be initiated promptly.

Wetlands in association with the Columbia River occur on the banks of the Columbia in proximity to the proposed contaminated area and background area. These wetlands are small in scale and are generally associated with the immediate bank of the Columbia River. Proposed FRC research would not occur in proximity to the wetlands and would not impact them.

The Ringold and Hanford Formations are continuous across the 100-H Area. Approximately 300 feet of suprabasalt sediment overlie the proposed FRC. The water table ranges from 0 feet at the Columbia River to 107 feet in depth. The direction of the groundwater flow is toward the river. Under high river flows, the direction of groundwater flow may be reversed for several hundred feet inland.

The contaminated groundwater underlying the 100-H Area is contained within a CERCLA operable unit (100-HR-3). Contaminants of concern within 100-HR-3 include chromium, nitrate, technetium-99, and uranium. This operable unit is currently undergoing interim remediation by a pump and treat system. There are extraction wells located along the river to intercept and remove contaminated groundwater, thereby protecting the quality of surface water (i.e., the Columbia River). Both the background and the contaminated area would be located hydraulically upgradient of the pump and treat system.

Because of the somewhat limited field site information available for both the background and contaminated areas, one of the first field activities that could be expected at both the background and contaminated areas would be a groundwater gradient test. As with most groundwater gradient tests, modification of the groundwater gradient due to pump/slug tests would be expected to alter the groundwater gradient over an area of several hundred feet and over a time frame of weeks. However, groundwater pumping and monitoring activities would not generate more than 14,000 gallons per year of purge water². These tests would not affect the existing direction of overall groundwater flow. The groundwater gradient would be expected to return to its pre-test level and the overall groundwater gradient would not be significantly altered.

As described in Appendix A, small quantities of nontoxic tracers, electron donors and acceptors, nutrients, microorganisms, or other substances might be injected as part of the in situ research activities. These substances might be injected either into the background or contaminated areas of the proposed FRC in accordance with best management practices and close monitoring of environmental conditions. Because the proposed contaminated area would be located in a CERCLA operable unit, permitting of discharges resulting from FRC activities would not be required. PNNL has obtained and currently holds several Categorical State Waste Discharge Permits that cover various categories of discharges, including experimental discharges from research activities. FRC work would be done within the bounds of these permits.

²In accordance with the Hanford purge water strategy, if groundwater were uncontaminated, it could be released onsite but not discharged directly to the Columbia River. If it were contaminated, it would be collected in tanker trucks until it could be transported to the ETF.

As described in Section 4.2.3.1.1, to better understand groundwater flow paths and speed, nontoxic and non-persistent tracers in concentrations ranging from 500 ppm to 10,000 ppm might be injected at both the background and contaminated areas of the proposed FRC. As with the tracers proposed for use at the ORNL FRC, the tracers proposed for use at the background and contaminated areas of 100-H would also be greatly diluted by diffusion into the matrix of the 100-H Area subsurface.

Nonreactive tracers proposed for use at the background and contaminated areas would not be expected to alter the groundwater chemistry if used. Reactive tracers could conceivably alter the groundwater chemistry, but their use would be tested in the laboratory prior to use in the field. Based on the laboratory studies, reactive tracers that would alter the groundwater chemistry would not be used at the background or contaminated areas.

To stimulate the activity and growth of microorganisms, electron donors or acceptors or other nutrients might be injected in concentrations ranging from 100 ppm to 300 ppm (i.e., 100 mg/L to 300 mg/L) at both the background and contaminated areas of the proposed FRC. At maximum, these concentrations would be lower than those that would be considered at the ORNL FRC. Injections at the background area would not occur in close proximity to the Columbia River (i.e., they would be more than 1,500 feet from the Columbia River).

As described in Section 4.2.3.1.2, injections at the contaminated area could be as close as 200 feet to the Columbia River and the most likely approach would be to use a push-pull approach. Again, approximately 95% of the injected materials could be recovered using the push-pull approach. With injection concentrations of up to 300 ppm, it is not likely that groundwater chemistry would be changed in a large area of the subsurface.

In some cases, electron donors, electron acceptors, or nutrients might be injected into one well and extracted from another. In such a situation, the proposed series of NABIR extraction wells and the existing pump and treat extraction wells would mitigate any potential for electron donors, electron acceptors, or nutrients to change the groundwater chemistry of large areas. For areas that would be changed such that a contaminant would become more mobile, the proposed NABIR extraction wells and existing pump and treat system would capture mobilized contaminants.

Possible shifts could occur in the existing microbial population due to the addition of electron donors, electron acceptors, or nutrients. However, at the low concentrations that would be used, changes in the microbial population would be limited in the area of the subsurface affected and would only persist if the electron donors, acceptors or nutrients were to continue to be added. Further information on the proposed use of electron donors and acceptors and nutrients at the FRC is available in Appendix A.

To determine whether it might be feasible to add microorganisms to a contaminated subsurface environment, a small quantity (2 X 10⁷ colony forming units per ml [cfu/ml]) of native microorganisms might be injected into the background and contaminated areas of the proposed FRC. As described in Section 4.2.3.1.3, native microorganisms would most likely be strains that would be isolated from the contaminated area and reinjected. Reinjection of native microorganisms would not be expected to be of concern either at the background or contaminated area. Although they would not be expected to move through the groundwater (Dybas et al. 1997), it is conceivable that they could survive. In some cases, the push-pull technique might be used to inject native microorganisms. In other cases, one injection and one or more different extraction wells might be used. In either situation, the microorganisms would be captured in the proposed NABIR extraction wells or in the existing pump and treat extraction wells.

If nutrients were to be added along with microorganisms, the added microorganisms could proliferate. While a proliferation of added microorganisms could effect a change in the groundwater chemistry such that a contaminant would be mobilized, any contaminants that might be mobilized would be captured either in the proposed NABIR extraction wells or in the existing pump and treat extraction wells.

As discussed in section 4.2.3.1.4, the two primary classes of other substances that could be injected would be biosurfactants and chelators. However, unlike the proposed ORNL FRC, PNNL would not consider using these two classes of substances either at the background or the contaminated areas. Because they would not be used, there would be no impacts to the groundwater.

In summary, it is anticipated that NABIR basic research at the proposed contaminated area would serve to better define the nature of existing contamination and aid in the development of bioremediation technologies to assist in clean-up of both groundwater and sediments in the 100-H Area. Overall, the hydrogeology and geochemistry of the 100-H Area would not be altered by the small-scale research activities. Groundwater gradient modifications, including pump/slug tests, would only temporarily alter groundwater characteristics and would not affect the existing direction of overall groundwater flow. Injection of tracers, electron donors and acceptors, nutrients, and microorganisms in the small amounts proposed would not be expected to alter the groundwater chemistry of the background or contaminated areas. In cases where a push-pull system were to be used, approximately 95% of the injected material would be recovered. In cases where separate injection and extraction wells were to be used, the proposed NABIR extraction wells would be used to recover injected materials. Secondary containment would be provided by the existing pump and treat system (EPA 1996). Through the use of the extraction well systems, impacts beyond the background or contaminated areas would not be expected.

The proposed contaminated area and background area would be situated in what has been botanically characterized as a shrub-steppe ecosystem commonly referred to as high desert. The region contains plant and animal species adapted to a semi-arid environment. The areas identified are previously disturbed areas of shrub-steppe habitat; therefore, the proposed action would not adversely affect native plant and animal species.

Biological resources within the proposed contaminated area and background area are typical of a high desert, shrub-steppe, arid environment. Most of the site has not experienced tillage or livestock grazing since the early 1940s. Extensive remedial activity is occurring in proximity to the proposed contaminated area and background area. As a consequence, it is unlikely that significant wildlife resources are in the area. Moreover, because research activities would encompass a very small portion of the proposed contaminated area and background area, it is not anticipated that wildlife or terrestrial resources would be impacted.

The U.S. Department of Interior, Fish and Wildlife Service provided a list of threatened and endangered species, candidate species and species of concern, which may be present in the Benton County portion of the Hanford Site. In addition, PNNL conducted a biological review of the proposed FRC (see Appendix E). The U.S. Fish and Wildlife Service and PNNL’s biological review concluded that there are no plant or animal species protected under the Endangered Species Act, candidates for such protection, or species listed by the Washington State government as state threatened or endangered within the proposed contaminated area or background area.

Bald eagle roost trees are located to the north and the south of 100-H Area. The Hanford Site Bald Eagle Site Management Plan (DOE 1994b) restricts routine work within 2,630 feet (800 m) of the roost sites between the hours of 10 a.m. and 2 p.m. Non-routine activities, such as excavations and well drilling, require case-by-case evaluations. However, the proposed contaminated area and background area would be located beyond the 2,630-foot radius from the night roost locations and would have no required restrictions.

Much of the land area encompassing the proposed FRC is located immediately adjacent to the Columbia River. The Hanford Reach of the Columbia River is an important spawning ground for the Upper Columbia River steelhead, the Upper Columbia River spring-run chinook salmon, and the bull trout. All three species are federally listed as endangered. These important fish species would not be expected to be impacted as a result of proposed FRC research. However, because of their importance and status as federal endangered species, the National Marine Fisheries Service would be notified under Section 7 of the Endangered Species Act prior to implementation of any field research. No other sensitive plant or animal species are known to occur either within the proposed FRC or adjacent areas.

According to PNNL, approximately half of the proposed contaminated area has been intensively surveyed for cultural resources (Appendix E). No archaeological or isolated artifacts were identified in the survey area. There are no known historic properties within the proposed contaminated area. The background area has also been surveyed for cultural resources. No cultural resources were located within the background area.

A portion of the proposed contaminated area is within about 440 yards (400 m) of the Columbia River. The Columbia River and its shorelines are considered culturally sensitive. Any intrusive research action conducted in this area would require a cultural resource expert to be present. Management of Hanford Site cultural resources follows the Hanford Cultural Resources Management Plan (PNL 1989). As such, any site in which development activities would be proposed would be evaluated prior to implementation of development plans.

The proposed contaminated area and background area would not conflict with any existing land use at the 100-H Area. The size and shape of the proposed contaminated area and background area were determined in part through discussions with the Hanford Environmental Restoration Contractor. The proposed field sites were positioned to avoid any interference with existing haul routes, potential remediation sites, or other ongoing or anticipated activities.

The proposed contaminated area and background area would not adversely affect recreation activities or recreational experiences on the Columbia River. Recreational users on the river would most likely not be aware of FRC activities in the region. The locations in which the proposed contaminated area and background area would be situated are not currently used for any other recreational purpose.

Trailers supporting proposed FRC research would be needed only in the vicinity of the proposed contaminated area and background area. They would be removed upon completion of research activities.

The proposed contaminated area and background area locations in the 100-H Area would not adversely impact any component of visual or aesthetic resources.

Socioeconomic impacts would be minimal. The work force required for installation and operation of the proposed FRC would be small and drawn from the existing work force. Visiting staff and scientists would contribute in a beneficial manner to the local economy by staying in local hotels and using local services. There would be no negative impact to the socioeconomics of the Hanford area as a result of FRC activities.

As described in Appendix C, PNNL would develop an overall Management Plan for the FRC that would explain the goals and objectives of the FRC, roles and responsibilities of FRC staff, procedures for investigators to follow, and procedures for storage of material and waste disposal. To address potential ES&H issues associated with human health and environmental protection, PNNL would also develop the following plans:

Although important for operating the proposed FRC, this EA seeks to evaluate potential impacts to human health and the environment prior to selecting the FRC. For purposes of this evaluation, health and safety issues to be evaluated include:

There are two primary human health issues associated with exposure to contaminated soils and groundwater from the contaminated area at PNNL. The first issue is potential radiation exposure from groundwater and soils/sediments with radioactive contaminants. The second issue is potential chemical toxicity of the contaminants that may be in groundwater and soils/sediments from the contaminated area.

Because of the proposed nature of operation, potential exposures could occur during drilling and sampling operations in the contaminated area and/or in the processing and analysis of samples obtained from the contaminated area. Such exposures could be to FRC staff or to scientists. To mitigate these potential exposures, a combination of personal protective equipment, personnel training, physical design features, and other controls (e.g., limiting exposure times) would be required to ensure that worker and visitor protection would be maintained for all proposed FRC-related activities. In addition, OSHA regulations that pertain to construction and well-installation would be adhered to in all situations.

For the majority of investigators, potential exposures would be from samples obtained from the contaminated area and would occur while they performed sample processing or analyses. For scientists and FRC staff, who would be involved with drilling and sampling operations, potential exposures would be from accidents associated with drilling and sampling operations in the contaminated area.

Title 10, CFR, Part 835, "Occupational Radiation Protection," establishes radiation protection standards, limits, and program requirements for protecting workers and the general public from ionizing radiation resulting from the conduct of DOE activities. For workers, 10 CFR 835 requires a 5-rem per year dose limit. For the general public, 10 CFR 835 requires a 100 millirem (mrem) per year dose limit. In addition, it requires that measures be taken to maintain radiation exposure as low as reasonably achievable. The 5-rem dose limit would be applicable to FRC staff and those scientists involved in drilling and sampling operations in the contaminated area. The 100 mrem dose limit would be applicable to scientists who process or analyze both soil/sediment and groundwater samples from the contaminated area.

For purposes of this EA, the maximum allowable exposure to FRC staff or to scientists was assumed to be 100 mrem per year. In addition, because potential exposures most likely would be during drilling and sampling operations, the following analysis of potential doses was assumed to be for hypothetical workers involved in drilling and sampling operations.

Doses to workers were bounded by evaluating a "bounding analysis" scenario, in the absence of any existing data on worker doses for this kind of work in the field. Workers were assumed to spill small amounts of soil/sediment (1 gram of contaminated soil/sediment five times per year for a total of 5 grams) or groundwater (1 milliliter of contaminated groundwater five times per year for a total of 5 milliliters) on themselves during the course of handling the core samples. To maximize the potential dose, it was further assumed that the workers did not wash off the contamination, but actually ingested it.

Radionuclide ingestion was calculated from the average measured activity values for H³, C¹⁴, Sr⁹⁰, Tc⁹⁹, U²³³, U²³⁸ and Am²⁴¹ in soil and groundwater (see Table 4-2). Where average values were not available, maximum measured values were substituted. The measured data provided in Table 4-2 were obtained from several sources including Liikala et al. 1988, DOE 1993, and Peterson et al. 1996). Totals were based on a yearly consumption of 5 grams of soil and 5 milliliters of groundwater. Dose factors for the Committed Effective Dose Equivalent were taken from the EPA report, "Limiting Values of Radionuclide Intake and Air Concentration and Dose Conversion Factors for Inhalation, Submersion and Ingestion, Federal Guidance Report No. 11" (EPA-5201/1-88-020), published in September 1988. The dose factor for C-14 was taken from the value for labeled organic compounds.

For the soil ingestion pathway, the total dose (for all radionuclides) came to less than 0.004 mrem/year, which is 25,000 times less than the limit of 100 mrem/year allowed for members of the public under 10 CFR 835, Section 208. The groundwater ingestion pathway is slightly smaller, with a total dose of approximately 0.002 mrem/year.

To estimate the total potential risk to workers from this "bounding analysis" exposure scenario, it was further assumed that the workers were exposed during the entire life of the project, which is ten years. The combined annual dose from both the soil and groundwater ingestion pathways was 6.16E-03 mrem per year (3.85E-03 + 2.32E-03). Over the ten-year lifetime of the project, the total dose was ten times that amount, or 6.16E-02 mrem. The lifetime fatal cancer risk is calculated by multiplying this ten-year dose by the dose-to-risk conversion factor of 4E-04 deaths per person-rem (NRC 1991). This calculation yields a lifetime risk of 3.08E-08, or roughly three in 100 million.

Soil Ingestion (5 g/y)					Groundwater Ingestion (5 ml/y)

Radionuclide	mrem/ pCi	pCi/g (max)	Total pCi	mrem/y	pCi/l (avg)	Total pCi	mrem/y
H-3	6.40E-08	0	0	0.00E+00	3455	17.275	1.11E-06
C-14	2.09E-06	13.2	66	1.38E-04	72	0.36	7.52E-07
Sr-90	1.42E-04	1.4	7	9.94E-04	9.9	0.0495	7.03E-06
Tc-99	1.46E-06	6.2	31	4.53E-05	303	1.515	2.21E-06
U-233	2.89E-04	0.46	2.3	6.65E-04	18.6	0.093	2.69E-05
U-238	2.55E-04	1.4	7	1.79E-03	2.38	0.0119	3.03E-06
Am-241	3.64E-03	0.012	0.06	2.18E-04	125	0.625	2.28E-03
			TOTAL:	3.85E-03		TOTAL:	2.32E-03

Although radioactive exposure would not be a problem, the potential chemical toxicity of the contaminants in the soils/sediments and groundwater from the proposed contaminated area also needs to be considered. Because the proposed contaminated area would be within the 100-HR-3 CERCLA operable unit, contaminant concentrations are evaluated according to CERCLA standards. Several recent studies of the 100-H Area indicate that only chromium and nitrate are of regulatory concern (Liikala 1998, DOE 1993, and Peterson 1996). Chromium concentrations are not at a level that would be of concern to human health, but they are high enough to be of concern to Columbia River salmon that spawn nearby. The CERCLA pump and treat system in the 100-H Area was put into place to extract the chromium so that it would not enter the Columbia River. Nitrate concentrations are also of regulatory concern, but unlike many organic contaminants, nitrate does not pose a cancer risk. Because groundwater from the contaminated area would not be used for drinking water, and because scientists would not consider drinking any groundwater collected either from the background or contaminated area, there would not be any potential for human exposure.

Reasonably foreseeable accidents associated with the proposed FRC could involve: construction accidents associated with well-drilling and sampling; striking a subsurface structure during drilling; spilling a tank of stored liquid chemical, such as glucose or acetate; and leaks of contaminated purgewater from fittings and valves.

Very few accidents associated with well-drilling/sampling or striking a subsurface structure have occurred recently at the Hanford Site (Dunigan 1999). For example, many years ago there was a fatality during a drilling operation. A drill operator became trapped in a well while trying to retrieve a drill component and suffocated. Over the past 20 years, there have also been a few instances where drill rigs were not properly stabilized and tipped over. In these cases the operators did not follow appropriate operating procedures.

Although spills of chemicals used at the background or contaminated area would be possible, the quantities of materials stored or transported onsite would be small (i.e., a few gallons of concentrated material or at most 55 to several hundred gallons of a one percent solution). For experiments where long-term injections of nutrients, tracers or other materials would take place, the rate of injection is likely to be less than ten gallons per day. Therefore, 200 to 300 gallons of diluted material would last at least two weeks.

A direct spill to the Columbia River would not be possible since the route from PNNL laboratories (where chemicals might be prepared) to the background and contaminated areas does not cross the Columbia River or any tributaries. In addition, FRC activities would not occur any closer than 150 feet to the Columbia River.

As discussed in Section 4.2.3, there would be no impacts to groundwater or surface water as a result of injection of the materials.

Activities to be undertaken at the proposed contaminated area and background area are listed in Section 2.2.3. Noise associated with drilling would be temporary and would potentially disturb wildlife or other sensitive receptors for only short periods during daylight hours. Drilling operators would be required to meet all OSHA requirements.

Noise levels would not exceed noises heard during routine daily activities. Decibel levels are below that considered to be harmful (see Figure 3-6). Noise from FRC activities would be temporary and likely to disturb wildlife or other sensitive receptors for only short periods during daylight hours.

Because of ES&H planning and controls, and the small-scale research expected at an FRC, there would be no adverse impacts to human health.

Washington Administrative Code (WAC) 173-303 requires the identification and appropriate management of dangerous wastes and the dangerous component of mixed wastes, and identifies standards for the treatment and land disposal of these wastes. The code would be applicable to wastes that are anticipated to be designated as mixed waste. DOE Order 435.1 provides requirements for radioactive waste control. WAC 173-304 requires the identification and appropriate management of solid wastes. It would be applicable to any solid waste generated at the proposed FRC.

In accordance with the Hanford Purgewater Strategy (July 1990), should purgewater contain levels of hazardous and radioactive constituents above agreed-to health and environmental-based criteria, the purgewater is sent to a central Hanford facility for future treatment and disposal. The "Strategy for Handling and Disposing of Purgewater at the Hanford Site, Washington" (WHC-MR-0039) was approved by DOE, EPA and Washington Department of Ecology on August 21, 1990. The strategy is incorporated by reference in Appendix F of the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement.)

All wastes would be evaluated and managed in compliance with the appropriate requirements. The regulatory standards would be met through the use of appropriate waste packaging and labeling; placement in designated waste storage areas, and routine inspections and maintenance. It is expected that solid wastes might be disposed of in the Environmental Restoration Disposal Facility (ERDF), the Low-Level Burial Grounds (LLBG), other Hanford Site waste control units, or at offsite permitted facilities. Liquid wastes would be disposed of in the ETF. Low-level radioactive contaminated materials might be disposed of in the LLBG.

The ERDF is designed to meet RCRA minimum technological requirements for landfills including standards for a double liner, a leachate collection system, leak detection, and final cover. It also meets performance standards under Title 10, CFR, Part 61 for disposal of low level waste. The LLBG meet the performance standards under 10 CFR 61. Any offsite facility to which dangerous waste would be sent would meet the requirements of RCRA.

Approximately 3,500 gallons of purgewater would be generated and considered waste for each research event. Four such events could be expected to occur each year. Purgewater would be collected in tanker trucks and disposed at the ETF. Soils waste is estimated to be approximately one-third of the total material removed during drilling. This would total approximately 275 kilograms per test bed. All wastes would be evaluated and managed in compliance with the appropriate requirements. The regulatory standards would be met through use of appropriate waste packaging and labeling; placement in designated waste storage areas, and routine inspections and maintenance. Best management practices would be instituted wherever applicable. The majority of non-hazardous solid waste material generated during drilling would be in the form of subsurface drill cuttings (soil materials). This soil material and bentonite clay would be used to backfill the test holes at the completion of field work. If there were any soil material remaining after backfilling, it would be distributed around each drill site.

Contaminated wastes (i.e., radioactive, chemical, and mixed wastes) would be handled under existing procedures for dealing with such wastes. All wastes generated from normal everyday activities by human workers, including biological wastes, garbage, and similar materials, would be kept in containment and exported from the work sites to proper disposal facilities, to preclude leaving any wastes behind during and at the termination of this activity. Trailers for the FRC would be equipped with portable chemical toilets, which would be serviced periodically.

Miscellaneous chemicals, acids (e.g., sulfuric, nitric and hydrochloric), bases (sodium hydroxide), reagents (e.g., Hach Kit), formaldehyde, or other chemicals used onsite for conducting chemical analyses and sample preparation might be infrequently transported. Generally, less than 2.2 gallons (one liter) of these chemicals would be used on a yearly basis. U.S. Department of Transportation (DOT) Hazardous Materials Regulations (Title 49, CFR, Parts 171-180) establish the requirements governing packaging and shipping of hazardous materials. These standards would be applicable to any necessary shipments of hazardous materials to or from an FRC.

The PNNL Shipping and Transportation Program ensures compliance with the DOT Hazardous Materials Regulations and DOE requirements specific to packaging and transportation safety. The PNNL Hazardous Materials Transportation Officer would be consulted to assure the safe packaging and transport of any regulated samples, hazardous materials, or wastes.

The existing facilities proposed to be used, as mentioned in Section 3.0, have ample office/laboratory space to allow for the addition of the small number of FRC staff and researchers. Because of the small number of people expected to work at the FRC, impacts to infrastructure features such as housing, education, health care, police and fire protection, and water and sewage would not be anticipated as a result of implementation of FRC research. Initiation of FRC-related activities likely would not require an increase in staff, as the majority of the activities could be implemented with existing personnel. Any additional personnel involved in FRC activities, such as visiting researchers, would not impact existing infrastructure.

Staging areas (approximately 100 x 100 feet) would be used for material and equipment laydown and as temporary satellite accumulation areas for wastes (in drums, tanks, or other containers) generated by characterization actions (e.g., drill cuttings and decontamination wastes). Staging areas would be operated and maintained in compliance with site waste control procedures for the duration of their operation and during setup of decontamination trailers/change houses. Staging areas would be established in previously disturbed areas (or in areas that would require minimal grading) and would be covered with gravel or gravel and geotextile material. Temporary access roadways (or temporary extensions of existing roadways) might also be constructed, as necessary. Clearing of low brush or removal of trees and shrubs with the goal of minimization of clearing might also occur.

No potential impacts have been identified that would affect other 100-H employees or offsite public. The vicinity surrounding the 100-H Area is large and the proposed action would not result in adverse human health or environmental effects on the public, including low-income or minority populations.

The Hanford Site NEPA Characterization Report (Neitzel et al. 1999) determined that the 100-H Area is located within a census block that contains no residents. Sections 4.2.3.1 and 4.2.3.3 state that there would be no impacts to surface waters (i.e., the Columbia River) or the groundwater. Therefore, there would be no impacts to individuals using the Columbia River for subsistence fishing or other subsistence purposes. There would be no disproportionate and adverse impacts to low-income and minority populations.

ENVIRONMETNAL ASSESSMENT FOR SELECTION
AND OPERATION OF THE PROPOSED
FIELD RESEARCH CENTERS

March 7, 2000

4.0

Environmental Consequences

4.2 Pacific Northwest National Laboratory/Hanford Site 100-H Area

4.2.1 Earth Resources

4.2.1.1 Topography

4.2.1.2 Geology

ENVIRONMETNAL ASSESSMENT FOR SELECTION AND OPERATION OF THE PROPOSED FIELD RESEARCH CENTERS