AR000001

SITE INSPECTION REPORT 

FOR THE 

NABESNA MINE 

NABESNA,ALASKA 

CERCLIS ID NO_.. AK0000333021 

Prepared for: 

Work Assignment No. 54-17-0JZZ 

Contract No. 68-W9-0054 

United States Environmental Protection Agency 

Region 10 

1200 Sixth Avenue 

Seattle, Washington 98101 

September 26, 1995 

Prepared by: 

URS Consulta nts, Inc. 

1100 Olive Way, Suite 200 

Seattle, Washington 98101 

URS DCN 62760.35.20.1043.45.bl 

I . 
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Nabcsn:i. Mine, Nabesna, Alaska Conte ts 

Site Inspection Report Page iii 

CO:\TEi\TS 

Section Pa2e 

ABBREVIATIONS AND ACRONYMS . ........ . .. . ... .. ................ vii 

1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 

2.0 SITE BACKGROUND .........-. . ..... . .. . . . ................... 2-1 

2.1 SITE LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 

2.2 SITE DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2- 1 

2.3 SITE PHYSICAL AND GEOLQ.GICAL CHARACTERISTICS . . . . 2-2 

2.4 SITE OPERATIONS AND WASTE CHARACTERISTICS . . . . . . . . 2-6 

2.4.1 Gold Mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7 

2.4.2 Gold Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8 

7__)- PREVIOUS SITE SAMPLING AND INVESTIGATIONS ......... 2-10 

3.0 EXPOSURE PATHWAYS AND POTENTIAL TARGETS .............. . 3-1 

3.1 GROUNDWATER PATHWAY ............ . ... ... . .. ... . .. 3-1 

3.2 SURFACE WATER PATHWAY ..... . ............. . ....... 3-2 

3.3 SOIL EXPOSURE PATHWAY . ..... . ..................... 3-3 

3.4 AJR EXPOSURE PATHWAY ....... .... . ....... . ......... 3-3 

4.0 SAMPLING PROGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 

4.1 OBJECTIVES A.!~D SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 

4.2 SA.!'v1PLING METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6 

4.2.1 Surface Soil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6 

4.2.2 Surface Tailings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6 

4.2.3 Subsurface Tailings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6 

4.2.4 Surface Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6 

4.2.5 Sediment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7 

4.3 ANALYTICAL AND HANDLING REQUIREMENTS ... ........ 4-7 

5.0 SA.!vfPLE RESULTS A.!"TD DISCUSSION . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1 

5.1 SOIL SAMPLE RESULTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2 

5.1.1 SVOC Analyses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2 

5.1.2 PCB Analyses . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . 5-5 

5.1.3 ·Pesticide Analyses ........ . ............. . ... ...... . . 5-5 

5.1.4 Inorganic Analyses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5 

5.1.5 Cyanide Analyses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6 

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Nabcsna ;\line, Nabcsna, Alaska Contents 

Site Inspection Report Page iv 

CO\'TE\'TS (Continued) 

Section 

SURFACE AND SUBSURFACE Mif\:E TAILI~GS . . . . . . . . . . . . . 5-6 

5.2.1 Inorganic Analyses of Mine Tailings . . . . . . . . . . . . . . . . . . . . 5-6 

5.2.2 Cyanide Analyses for Mine Tailings . . . . . . . . . . . . . . . . . . . . . 5-8 

5.3 SURFACE WATER SAMPLE RESULTS ........ . . .......... 5-8 

5.3.1 Inorganic Analyses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8 

5.3.2 Cyanide Analysis .. . ........ . ...... . ..... . . .. ....... 5- 10 

5.3.3 Hardness Analysis . .... . . ................ . . . ........ 5- 10 

5.4 SEDIMENT SAMPLE RESULTS ......... . .. .. ... .... . ... .. 5-11 

5.4.1 SVOC Analyses ..... . . . · .. ...... . ... ................ 5-11 

5.4.2 PCB Analyses ....... . . . . .. . .............. .. ....... 5-1 2 

5.4.3 Pesticide Analyses . . ...· . . .. .. .. . .. ...... . . .......... 5-12 

5.4.4 Inorgani~ Analyses . ... .... ...... . ... .. .... . ... ..... 5-12 

5.4.5 Cyanide Analysis .. ........ . ..... . . . . ....... ...... .. 5-1 2 

5.5 INVESTIGATION-DERIVED WASTE ............. . ........ 5-14 

5.6 QUALITY CONTROL SAMPLES .. . ........... . ... ...... .. 5-14 

5.7 SUMMARY .... . .. . ............. . .. . . . . ... . ..... .. . . . . 5-14 

6.0 REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1 

APP EN DI XES 

A PHOTOGRAPHIC LOG OF JUNE 20-21 , 1995, SITE VISIT 

B USGS MAP OF THE GEOLOGY OF THE AREA 

C CROSS-SECTION MAP OF THE :-IABESNA MINE 

D DIAGRA.iv[S OF UPPER At'\JD LOWER MINE TAILINGS 

E CYA.!\TIDE PROCESS FLOW CH.ART 

F WELL LOG 

G NET PRECIPITATION 

H DA.TA RESULTS AND VALIDA.TIO .. 

I GEOCHEMICAL DATA FOR E;\VIRONME1 T-\L STUDIES AT NABES~A 

6276019509.065\TOC 
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Nabcsna Mine, Nabesna, Alaska Contents 

Site Inspection Report Page \i 

ANILCA 

bgs 

CERCLA 

CFR 

DQO 

EPA 

IDW 

MS/MSD 

Nabesna 

NRHP 

NPL 

NPS 

PCB 

QMP 

SAM 

SARA 

SI 

SQL 

SVOCs 

TSOP 

URS 

ABBREVIATIO NS Al'-:D ACROi'-tYMS 

Alaska National Interest Lands Conservation Act of 1980 

below ground surface · 

Comprehensive Environm·encal Response, Compensation, and 

Liability Act of 1980 

Code of Federal Regulations 

data quality objective 

United States Environmental Protection Agency 

investigative-derived waste 

matrix spike/matrix spike 'd.uplicate 

Nabesna Mine 

National Registe r of Historic Places 

National .Priorities List 

National Park Service 

polychlorinated biphenyl 

Quality Management Plan 

site assessment manager 

Superfund Amendments and Reauthorization Act of 1986 

site inspection 

sample quantitation limit 

semivolatile organic compounds 

Technical Standard Operating Procedures 

URS Consultants, Inc. 

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Nabcsna :Vfi ne, Nabesna, Alaska Contents 

Site Inspection Report Page v 

fI GURES 

Pa£e 

2-1 Vicinity 1\ ·lap ... . ...... . ...... ......... ..... . . ... . 2-3 

2-2 Aerial Photograph of Site .. . ... ... ..... . . . .. .. ..... . . 2-4 

2-3 Nabesna Mine Site Map .. . .......... ...... . . ..... . . 2-5 

4- 1 On-Site Sampling Locations . . .. ........ . . ......... . . . 4-4 

4-2 ·Off-Site Sampling Locations ................ .. ... .... . 4-5 

TABLES 

Page 

2-1 Site Ope rations and Ownership . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9 

2-2 Summary of Environmental Fate and Transport of Cyanide From 

Mining Wastes .... , .. .. .. ..... . .... .. .. . ........ .... ..... . ... 2-I I 

2-3 Previous Sampling Resu lts ................ . . .... .... . . .. . ....... 2-1 2 

3-1 Groundwater Drinking Populations Within 4 Miles of the Site . . . . . . . . . . . 3-1 

3-2 Stratigraphy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 

3-3 Description of Surface \.Vater 15 Miles Do\vnstream ... .. . .. .... ...· . .. . -3-2 

3-4 Residents and Wetland Acreage within a 4-Mile Radius . . . . . . . . . . . . . . . . 3-4 

4-1 Sample Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2 

5- 1 Significance Criteria for Chemical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1 

5-2 Semivolatile Organic Compounds in Surface Soil . . . . . . . . . . . . . . . . . . . . . 5-2 

5-3 PCBs/Pesticides in Sediments, Soil, and Rinsate . . . . . . . . . . . . . . . . . . . . . . 5-3 

5-4 Inorganics in Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4 

5-5 Inorganics in Tailings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7 

5-6 lnorganics in Surface Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9 

5-7 Surface Water Properties . . . ... .......... . .... . ... . .... . .... .... 5-10 

5-8 Sem.ivolatile Organic Compounds in Sediments .. . ....... . ... . ....... 5-11 

5-9 Inorganics in Sedimen ts ... ... .. . .. ..... . .. . .................... 5-13 

5-10 Sem.ivolatile Organic Compounds and Inorganics in Equipment Rinsate 

and Laboratory Method Blanks . ..... . .... . ........... . .......... 5-15 

5-11 Summary of Signifi cant Concentrations of Chem.icals From the 

N2.besna Mine .. .... ... ............... . ... .. .. .. . . ... .... .... 5-1 6 

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Nabcsn:i Mine, Nabesn:i, Al:isb Section 1.0 

Site I nspcctiun Report Page 1-1 

1.0 Ii\TRODUCTION 

Pursuant to United States Environmental Protection Agency (EPA) Contract ~o. 

68-W9-0054 and Work Assignment No. 54-·17-0JZZ, URS Consultants, Inc. (URS) has 

conducted a site inspection (SI) of the Nabesn:a Mine (Nabesna) site located at Milepost 

46 on the Nabesna/Slana Road, Nabesna, Alaska. This SI was conducted under the 

authority of the Comprehensive Environmental Response, Compensation, and Liability 

Act of 1980, as amended by the Superfund Amendments and Reauthorization Act of 

19S6 (SARA). The SI process is intended to (1) document a threat or potential threat to 

public health or the environment posed by a site; (2) identify if a potential emergency 

situation exists that may require an immediate _response; (3) document the presence or 

absence of uncontained or uncontrolled hazardous substances on a site; and (4) confirm 

site characteristics and area receptor information collected during the preliminary 

assessment. The SI is intended to collect sufficient data to enable evaluation of the site's 

' potential for inclusion on the National Priorities List (NPL), and, for those sites 

determined to be NPL candidates, establish priorities for additional action. The SI 

process and this SI do not include extensive or complete site characterization, 

contaminant fate determination, or quantitative ecological or human health risk 

assessment. 

Sections of this document present specific information regarding the Nabesna SI: 

• Section 1.0: Introduction-provides a description of authority and purpose

• Section 2.0: Site Background-provides a summary of site-related 

information 

• Section 3.0: Environmental Pathways and Potential Targets-includes an

evaluation of specific pathways 

• Section 4.0: Sampling Program-includes a synopsis of sampling 

conducted 

• Section 5.0: Sample Results and Discussion-provides a discussion of 

sampling results 

• Section 6.0: References- provides a list of references 

61760\9509 .065\SECTION I 
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\ ...... Source: National Park Service, 1994; 

Nabesna Mine Figure 2-3 URS Nabesna, Alaska Nabesna Mine Site Map SITEINSPECTION 

CONSULTANTS 

~ 16276035--4-112995 

AR000007
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Nabesna Mine, Nabesna, Alaska Section '2.0 

Site Inspection Report Page 2-1 

2.0 SITE BACKGROUND 

2. 1 SITE LOCATION 

Site Name: Nabesna Mine 

CERCLIS No: AK000033302 l 

Location: Milepost 46, Nabesna/Slana Road 

Nabesna, Alaska 

Latitude: 62.22'20.0" North 

Longitude: 143 ·o· 17.0" West 

Legal Description: Section 21, Township 7 North, Range 13 East 

Site Owner: Mr. Kirk Stanley 

Ptarmigan Company, Inc. 

P.O. Box 200956 

Anchorage, Alaska 99520 

(907) 333-5639 

Site Operator: Site is currently inactive 

Site Contact: Mr. Kirk Stanley 

(907) 333-5639 

2.2 SITE DESCRIPTION 

The Nabesna site, which consists of a gold mine, is located in the White Mountains in 

the northern portion of the Wrangell-Saint Elias National Park and Preserve. This area 

is located in the southeastern section of Alaska; approximately 300 miles east of 

Anchorage. Gold mining operations began in the early 1900s and continued until the 

1940s. The site is a privately owned, patented mining claim (the Sunshine Lode), which 

is one of several mining claims in the area owned by the Ptarmigan Company. The 

mining claims are situated within the \Vrangell-Saint Elias National Park and Preserve. 

The land south of the site is part of the National Park Service (NPS), which was 

62760\9509.065\SECTION2 
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Nabesn:i Mine, Nabesna, Alaska Section 2.0 

Site Inspection Re port Page 2-2 

established in 1980 by the AJaska National Interest Lands Conservation Act of 1930 

(A:\lILCA). Figure 2-1 shows the general location of Nabesna and the surrounding area. 

Appendix A includes a surface water distance map and a photographic log of the site 

visit and sampling conducted on June 20 and 21, 1995. 

The site consists of the mill, on-site tailings, and the surrounding area, which comprises 

the remaining structures that supported minii1g activities (i.e., the Nabesna Mine Ghost 

Town). The assay office, machine shop, boiler house, mess hall, several miners' cottages, 

the fo reman and superintendent houses, the horse barn, and the boardwalks remain on 

site. The store, dispensary, post office, and tram terminal used during mining activities 

were in ruins by 1978. The lower tailings that we re produced from on-site mining 

activities are east of the site on an unpa tented claim on National Park Service property. 

The Nabesna gold mine district (including the mill, ghost town, and on-site tailings) is 

listed on the National Register of Historic Places (NRHP). Figu re 2-2 is a copy of an 

aerial photograph of the area surrounding the mine. Figure 2-3 presents a detailed map 

of the Nabesna site (USDOI, 1978). 

The Nabesna mill building (where the ore was processed) and the upper mine shafts are 

located at an elevation of 3,100 and 3,800 feet above sea level (ASL), respectively. The 

land continues to slope and drain into the Nabesna Rive r (elevation 2,500 feet) 

approximately 5 miles to the east. Cabin Creek is located 0.25 mile southwest of the 

site. Cabin Creek courses below ground lev·el and re-emerges south of the mill, flows 

approximately 4 miles, and joins Jack Creek, wbich flows approximately 5 miles before it 

merges \vith the Nabesna River, which is fed from the Nabesna Glacier (Stanley 1995). 

2.3 SITE PHYSICAL A!"1D GEOLOGICAL CHA.RACTERJSTICS 

The Nabesna mine is located at the base of White Mountain in the Nabesna River 

valley. The rocks of the White Mountain area include the Nabesna limestone of upper 

Triassic age, which is underlain by basaltic lavas and some dark shales of possible 

Permian age and intruded by stocks and dikes of quartz diorite and andesite. These 

rocks are overlain unconformably by Wrangell lava of Tertiary and Quaternary age. The 

quaternary period is also represented by fluvia tile deposits, lateral moraine, talus, and 

fan rubble. Nabesna limestone is the host rock of the gold deposits of ·wbite Mountain. 

The three types of mineralization occurring from erosion of the limestone are magnetite 

\vith pyrite, calcite, and some gold; veins and masses of pyrrhotite with or without pyrite 

and gold; and veins of auriferous pyrite \vith calcite (Wayland 1943). Appendix B 

includes a map of the geological formation of the area. 

62760\9509.0651SECTION2 
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AR000010

Nabesna Mine

Nabesna, Alaska

SITE INSPECTION 

Figure 2-1 URS Vicinity Map · CONSULTANTS, INC. 

41627603$-2·112995 
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N;ibesnu Mine, N;ibcsnJ, Alaska Section 2.0 

Site Inspection Report Page 2-6 

The terrain is typical of a glaciated mountainous region, with rugged to precipitous 

highlands cut by the wide, relatively flat Nabesna River valley. The toe of the Nabesna 

Glacier, which feeds the river, is located about 13 miles south of the site. The timberline 

is at an elevation of about 3,500 feet. The main valleys are wooded (spruce and birch), 

and the mountain slopes are generally bare or tundra-covered. The slopes are typically 

brushy (willow and alder) at the timberline. The yearly temperature range is 

approximately -40 degrees to 85 degrees Fahre nheit, and the annual precipitation is 

approximately 20 inches (WGM Inc. 1981). 

2.4 SITE OPERATIONS AND WASTE CHARACTERISTICS 

Prospecting for gold in the White Mountain area reportedly began in 1899 when 

prospectors traveling to the Klondike district p,,rnned for gold in the gravel at the foot -of · 

the mountain's 1,500-foot limestone cliff (at an··altitude of 6,400 feet) (\Vayland 1943). · 

Between 1903 and 1905, A.J. Fjeld and Paul Paulson located 28 claims in the White 

Mountain area. In 1906, Fjefd and Paulson formed the Royal Development Company. 

The claims were mined and prospected by the company until 1914 when the claims 

lapsed. The claims were relocated, worked, and again lapsed by unnamed prospectors 

between 1914 and 1924 (Wayland 1943). 

In 1922, the area near what was to become the Nabesna mine site was first prospected 

by Mr. Whitham. In 1924, Mr. Whitham relocated the claims associated with the Royal 

Development Company, and in 1925, the Bear Vein was discovered. It was documented 

that a bear dug out a gopher in a moss-covered outcrop of White Mountain; 

Mr. Whitham enlarged the bear's d{ggings and found the rich gold ore vein. The Bear 

vein is the principal vein of the present Nabesna mine, which is 1,000 feet northeast of 

the principal vein of the Royal Development Company. During the next 3 years, 

Mr. Whitham made a SO-foot cut on the vein, sank a 30-foot shaft in the outcrop, and 

exposed the vein at what is now the portal of the drift (tunnel) at the 100-foot level 

(100 feet below the outcrop) (Wayland 1943). 

In the fall of 1929, the Nabesna .Mining Corporation was formed and funding was 

available to develop the mine. By 193 1, a tram had been built to the mill site at the 

base of the cliff. The mill site, which began operating that same year, contained a 

crusher and a Hardinge ball mill (\vbich \vas later replaced with a Marcy bail mill). Also 

in 193 1, a permanent camp was under construction and work began on the 250-foot level 

(250 feet below the top of the outcrop). In 1933, work began on the 650-foot level 

(650 feet below the top of the outcrop) (Wayland 1943). Appendix C contains crosssectional diagrams of the mine. 

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Nabesna Mine, Nabesna, Alaska Sect.ion 2.0 

Site Inspection Report Page 2-7 

The original outcrop of the Bear Vein contained pieces of flinty quartz carrying pyrite. 

Other vein minerals included fine crystals of pyrite, cerussite, marcasite, and anglesite. 

The vein was light gray with a dark gray streak near the middle that contained cerussite 

and anglesite. Gold pann.ing done from the vein indicated considerable free gold. The 

gold ,vas irregular in shape (not angular) and stained a dark color (Wayland 1943). 

2.4.1 Gold Mining 

Lode deposits are mined by either underground· or open pit methods, depending on 

factors such as the size and shape of the deposit, the ore grade, the depth of deposit, and 

the mineralogical characterization of the ore (U.S. EPA 1978). Gold-bearing veins occur 

in steeply dipping veins and mineralized fault zones and are rarely uniform in value or 

size. Portions of the veins that contain minabk quantities are termed "ore shoots" or 

"ore bodies." The ore shoots at Nabesna ranged in thickness from a few inches to 

35 feet (averaging 5 to 7 feet). Underground mining was necessary to reach the veins. 

The mines would be develop~d by horizontal shafts or adits -with haulage levels at -

convenient levels (e.g., 100 feet, 250 feet, and 650 feet). Raises (tunnels) are run in the 

ore or just beneath it from level to level. Ore is then drilled and blasted from the v_ein, 

loaded into ore cars, and taken to the surface or portals. The total workings of the 

Nabesna mine included sLx levels (interconnected with manways and ore chutes) and 

totaled approximately 16,000 linear feet. All the ore was hand trammed to the portals, 

then lowered 2,000 feet by a gravity system aerial tram to the mill. The gold was 

recovered by shaker tables, flotation, and cyanide leaching (see Section 2.3.2 for details) 

(Brooks 1968; WGM Inc. 198 1; Spude 1984). 

Most of the known ve ins near the Bear Vein were worked out by 1939. At the beginning 

of World War II, the Nabesna Mine was closed by U.S. War Production Board Order 

L-208. This presidential war order decreed that only-mining activities directly supporting 

the \var effort would be permitted to continue. In the late 1940s, the U .S. Army-Counter 

Intelligence organ.ized and operated an underground force in Alaska because of the 

potential threat of a Russian invasion. The tunnels in the mines were used for storage of 

supplies and arms. A drift from the Royal Development Company mines was used 

between 1947 and 1949. In 1949 the arms and supplies were removed from the nearby 

mine and access was restricted by a locked door to the entrance of the drift, \vith a No 

Trespassing by order of the U.S. Government sign (Stanley 1995). The mine reopened 

briefly after the war. However, with the death of i'v1r. \Vbitham in 1947 and the 

depletion of high-grade ore, the mine closed (\VGM Inc. 1981; Spude 1984). 

After the mine c!osed, the Ptarmigan Company, which acquired the property in the early 

1960s, attempted to recover gold from the old tailings. In 1980, Minex-Alaska, Inc., the 

predecessor of. 12.besna Corp. ·Limited, also attempted to recover gold from the upper 

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Nabesna Mine, Nabesoa, Alasb Sect.ion 2.0 

Site Inspection Report Page 2-S 

and lower tailings. The first attempt consisted of a crude cyanide leaching process, while 

the second attempt con·sisted of a sluicing operation. Neither attempt was successful 

(WGM Inc. 1981; Stanley 1995). The site tailings have been assessed and analyzed 

periodically since the 1980s to determine the feasibility and profitability of recovering 

gold from them. Currently, no mining is occurring on site. The mine is occasionally 

visited by tourists, visiting the Wrangell-Saint Elias National Park and Preserve. On 

May 25, 1979, the Nabesna Gold Mine District was listed on the NRHP (Saleeby 1995). 

Geologists from the Un.iversicy of Miami have studied ancient fossilized marine life, 

geologic formations, and geochemical studies at the Nabesna site (Stanley 1995; 

NPS 1995). 

During the gold mining operation at Nabesna, over 2.5 tons of gold, approximately 5 tons 

of silver, and many tons of copper and lead w~re processed (USDOI 1978). Table 2-1 

summarizes site operations and ownership. ·· 

During the mining operation, approximately 350,000 cubic yards of waste rock (tailings) 

was produced from the 70,000 tons of ore removed from the mountain and comprise 

·· approximately 2.1 acres. In the late 1980s, some of the upper tailings were containerized 

into 55-gallon barrels for shipment to a smelter in Tacoma, Washington, for gold 

extraction, after being sluiced to remove the clay particles. However, the barrels were 

not shipped, so the tailings remain in approximately 40 open-topped barrels located 

on site (Wayland 1943; NPS 1986; Stanley 1995). The tailings that had been produced 

from the ore process using the cyan.ide leaching system during the season of 1938 had 

been piped, using wooden troughs, to an unpatented area of the claim (referred to as the 

lower tailings) (Stanley 1995). Appendix D contains diagrams of the upper and lower 

tailings. Refer to Figure 2-3 for a map of the Nabesna mine site. 

2.4.2 . Go ld Recovery 

Gold occurs chiefly as the native metal. In ores, it is often too small (in particle size) to 

be seen with the unaided eye. It is recovered from the ore by several processes. The 

treatment utilized depends □ the mineralogical character of the ore. Each process 

requires crushing and fine grinding. Free gold and gold-bearing sulfide minerals may 

then be removed from the ground ore by amalgamation, shaker tables, flotation, and 

cyanidation. Free goid recovered by cyanidation is sold as bullion (Brooks 1968). 

The amalgamation process involves adding mercury to the grinding unit so an amalgam 

of gold and mercury is formed, which is caught on mercury coated copper plates and 

then scraped off. The gold is then recovered by distilling off the mercury. 

Amalfrnmation was attempted . at Nabesna but was unsuccessful because of an oxide film

on the 

~ 

gold (Wayland 1943). 

62760\9509.065\SECTION2 
AR000014

Nabesaa Mine, Nabesna, Alaska Seclioa 2.0 

Site Inspection Report Page 2-9 

Table 2- 1 

Site Operations and Om1ership 

I Date 

1922 

1924 

1925 

[929- 1930 

193 [-1939 

Late 1940s 

1945-1960 

1960- 1969 

I Site Ownership 

Carl F. Whitham

Carl F. Whitham 

Carl F. Whitham 

Nabesna Mining Corporation 

Nabesna Mining Corporation 

Nabc.:sna Mining Corporation 

Nabesna Mining Corporation 

' 

Ptarmigan Company

/Kirk Stanley 

I 

Began prospecting in the area 

Discovery of the Bear vein 

operations. 

been worked 

Army as an arms and supply cache 

higher than quality of ore 

Site Operatioas

~~location of the Royal Development Company 

Org11nization of the mining corporation, selling 

of stocks to finance the construction and mining 

Mining operations until most of known veins had 

R:oyal Development Company Mine used by U.S. 

Tried to reopen the mines, cost of production 

Prospected and conducted assay surveys to 

determine value of gold in tailings, cyanide leach 

I 

Source: 

process 

1980 Minex-Alaska Prospected and conducted assay surveys to 

determine value of gold in tailings, sluicing 

process 

1986 Nabesna Corporation Limited Environmental Assessment and Analysis of 

(Ow11ership of tailings) tailings for potential cyanide leach heap process 

for tailings 

1960- Ptarmigan Company Prospecting and conducting assay surveys to 

present / Kirk-Stanley determine location and value of gold in ore

WGM Inc. 1981; Stanley 1995; National Park Service 1978 

The shaker table process involves placing the ore on a screened table after it has been 

crushed, shaking the table, and sifting the gold from the ore. 

The flotation process involves combining finely ground ore with water, agitating it, <!-Dd 

aerating with small amounts of certain compounds such as pine oil, which adheres to the 

desirable minerals and floats them to the surface, where they are skimmed off as a 

concentrate (Brooks 1968). The concentrates were then shipped to the Tacoma, 

Washington, smelter (Brooks 1968; Spude 1984). 

Tne cyanidation process, involves placing finely crushed ores or concentrates in vats 

containing a dilute solution of sodium or potassium cyanide. The gold dissolves to form 

62760\9509.065\SECTION'.2 
AR000015

N:ibesn:i Mine, Nabesna, Al:isk:i Section 2.0 

Site Inspection Report Page 2-10 

sodium or potassium gold cyanide. The solution is then brought into contact ,vith zinc or 

aluminum, which causes the gold to precipitate (Brooks 1968; EPA I 978; Smith 1982). 

Appendix D contains cyanide process flow charts. 

The following chemical reactions occur when cyanide is used in the gold recovery 

process: 

0 2 + 2H20 + 2 e· -+ 2 OH· + H20 2 

Au -+ Au+ + e· 

Au + + CN· -+ AuCN 

AuCN + CN· -+ Au(CN)"2 

The overall reaction is presented below: 

This gold cyanide compound is then mixed wi th zinc or aluminum, ~ hich causes the gold 

to precipitate. Zinc or aluminum cyanide is the resulting waste product of this process. 

Cyanide and acid releases from mining wastes may occur through runoff from waste piles 

during storm events; leaching of constituents from waste piles by infiltrating rainwater; 

seepage of constituents through the bottoms of tailings ponds; runoff to surface water, 

percolation into groundwater; and the atmosphere. Some ores contain metals that form 

insoluble, stable, metallo-cyarude complexes that do not readily leach or dissociate 

(Versar 1986). 

The rate at which cyanide is released into the environment is determined by the 

molecular state of the cyanide; the pH of the waste material; the permeability of the 

impoundment liners, and the temperature (which affects various natural degradation 

processes) (Versar 1986). Cyanide present in wastes degrades biologically and 

chemically at varying rates ( degradation processes result in significant reductions in 

cyanide concentrations in older wastes) (Versar 1986). The environmental fate and 

transport of cyanide is presented in Table 2-2. 

2.5 PREVIOUS SITE SAMPLING A.ND Ii'tVESTIGA.TIONS 

In August 1981, WGM, Inc., examined the rr1ine tailings to determine their extent, 

thickness, and volume. In addition, assay tests were conducted to determine the content 

of gold and silver per ounce per ton of tailings. The sample results are shown in 

Table 2-3. Results from the assay tests indicated that the upper tailing deposit bas a 

6276019509 .065\SECTION2 
AR000016

Nabcsna 1'-line, l':abe , Alaska Section 2.0 

Site Inspection Report Page 2-1 1 

Ta ble 2-2 

Summary of Enviro nmental Fate and Transport of Cya nide From Mining Wastes 

Environmental Process I Summary Statement 

Photolysis HCN is virtually uru:eactive in the troposphere and probably diffuses to 

the: stratosphcrc before .b.eing destroyed. Some metallocyani<les 

(fcrrocyanidc and krricyanide) can bc decomposed by sunlight in watcr 

to yield iron hydroxide and cyanide ion. 

Oxidation Free cyanide is not oxidized in air or water by molecular oxygen or 

hydroxyl radic:ils, but it is oxidized by polysulfides and poly1hionates in 

high sulfur ores to thiocyanate ion. Iron-rich ores may also promote 

the oxidation of cyanide through form:ition and decomposition of 

ferricyanide. : ' 

Hyd rolysis Hydrolysis of the CN bon·d of cyanide in mining wastes is too slow to 

be relevant as a fate process. Degradation of metallocyanidc complex.es 

can be considered to be their hydrolysis with rdease of cyanide ion. 

Thii; bttcr process may be responsible for maintaining low levels of free 

cyanide in old waste piles. 

Volatilization If the alkalinity of li quid wastes is assumed to be pH 8-9, the half-life 

for volatilization of free cyanide is estimated to be 0.4 - 4.0 days. 

Volatilization from solid waste piles is much slower with a half-life that 

probably varies from several months to a few years. 

Sorption Free cyanide and most com plex. cyanides are sorbed to only a small 

extent and are therefore mobile in the environment. The exception is 

some complex cyanides which are sparingly soluble and are therefore 

apparently immobile. 

Bioaccumulation Free cyanide does not accumulate but some metallocyanides may 

accumulate in fish. 

Biodegradation Biodegradation of cyanides may be universal, but most organisms can 

only tolerate very low concentrations. Some microbial cultures can 

become acclimated to higher concentrations under aerobic conditions, 

but anaerobic degradation may proceed only at concentrations of a few 

parts per million. 

Notes: 

CN Cyanide 

HCN Hydrogen cyanide 

Source: Versar Inc. 1986. 

6276019509.0651SECTION2 
AR000018

Nabesna Mine, Nabcsna, Alaska Section 2.0 

Sile Inspection Report 1'.ig<.: 2- 12 

Table 2-3 

Previous Sampling Results 

1981 WGM Inc. 

Samples of . 

Inorganic Mine Tailings . 

A ntimony NA 

Arseni<.: NA 

Cobalt 57 ppm 

Copper 3,400 ppm 

Iron NA 

Lead 3,900 ppm 

Molybdenl!m 7 ppm 

Silver NA 

Zinc 2,700 ppm 

1983 BondarClegg Snmplcs 

of Mine Tailings 

140 ppm 

1,300 ppm 

NA 

2,000 ppm 

NA" 

2,400 ppm 

NA 

NA 

2,000 ppm 

1994 NPS 1994 NPS 1994 USGS 

Samples of Dri11ki11g Background 

Mine Tailings Water Wells Surface Water 

NA NI\ 0.0002 ppm 

326 ppm < 0.003 ppm 1).0043 ppm 

36.0 ppm < 0.018 ppm < 0.002 ppm 

2,660 ppm < 0.005 ppm .- 0.0ll2 ppm 

)21,000 ppm 0.019 - 0.136 ppm 0.02 ppm 

3,360 ppm < 0.002 ppm < 0.005 ppm 

NA NA 0.021 p pm 

100 ppm NI\ < 0.000 I p1"iin 

83 ppm NA NA 

199-1 US(;s 1994 usr;s 

Surface Waltr l.A·m:halc Below 

lh·low Tailings Tailings 

< 0.0002 ppm < 0.1 ppm 

< O.OOOS ppm 4.0 ppm 

0.0lJ2 ppm 0.9 ppm 

0.0 13 ppm '.l.'.'i ppm 

0.7 ppm 1•170 p pm 

< 0.005 ppm (,.0 ppm 

< 0.0lJ•I ppm 0.0].'i ppm 

< 0.000 I_ppm 17.0 ppm 

NA NA 

t 9~M usc;s 

S11rl'nn: \Valer 

Scdimt·11t Bdow 

Tailings 

•1.-1 ppm 

100 ppm 

27.0 ppm 

4 10 ppm . 

<J.7 pcl 

140 ppm 

4.7 ppm 

7.0 ppm 

10.0 ppm 

Noles: 

NA Not analyzed 

< Not detected; value shown is deteclion limit 

pct pe rcent 

So urce: !-)RS 1995; USDOl 1995, Appe ndix I 

6276019509.065\TBL2-3 
AR000019

Nabesna l\ line, Nabesna, Alaska Sectioo 2.0 

Site Inspectio n Repo rt P:?ge 2-13 

rel:Hi,·ely high gold content. "hi;e 1he lower 1ailings deposit ma\" be considerably 10,1:cr in 

grade. The resu lts also indicate 1hat a positi,·e rela1ionship may e)Jst between gold 

content, copper, and cabal!, and a nega1i,·e relationship may exist between gold and zinc 

(LRS 1995). 

In 1993, Banda r-Clegg &. Company Limi1ed of Canada analyzed 1he mine railings ior 

inorganics at the requ es1 of the U.S. Bureau of- 1\-lines. The results of this analysis are 

pro,·ided in Table 2-3. The results of the samples taken from the tailings indicate high 

concentrations of inorganics. Background samples were not collected for comparison 

(U RS 1995). 

In 199-+, the Wrangell-Saint Elias ~a1ional Park and Preserve collected and analyzed soil 

samples of the tailings and water samples frorJ? .the t,·vo drinking water wells closest to 

1he site (Table 2-3). The resu lts from the sampling indicate that the inorganics present 

in the tailings are not present in the drinking water wells (NPS 1994). 

In 1994, the United States Department of the Inte rior, Division of Geological SurYey, 

conducted environmental geocherrucal studies of the Nabesna mine and surrounding area 

to determine the extent of possible environmental hazards associated with historic mining 

areas and to establish pre-mining background levels for selected elements (Table 2-3) 

(US DOI 1995). 

In November 1993, the Nabesna Mine site was reported to the EPA by citizen petition. 

On June 20 and 21, 1995, URS Consultants, Inc., performed a site screening investigation 

that included the collection of surface water, sediment, soil, and mine tailing samples. 

The owner of the mine and an environmental specialist from the Wrangell-Saint Elias 

National Park and Preserve accompanied URS. The results from the sample analysis are 

presented in Section 5. 

6276019509.065\SECTION2 
AR000020

Nabc=saa Mine, Nabesaa, Alaska Section 3.0 

Site! Inspection Report Page 3-I 

3.0 EXPOSURE PATHWAYS AJ'-1D POTENTIAL TARGETS 

3.1 GROUNDWATER PATHWAY 

Groundwater levels near Nabesna range from-42 to 81 feet below ground surface (bgs), 

and the groundwater flow is toward the northeast. 

There is a well on site that was used for the mining operations; however, its use has long 

since been discontinued. Water for the operation of the mine was also piped with 

wooden troughs from Cabin Creek to the site (Stanley 1995). 

Devil's Mountain Lodge is a hunting and fishing guide outpost located approximately 

2 miles northeast of the mine site. The lodge owners/operators and their extended 

families live in the area and use private domestic wells (Ellis Well and Stanley Well) for 

drinking water and irrigation tsee Table 3-1). 

Table 3-1 

Groundwater Drinking Populations 

Within 4 Miles of the Site 

Number of Domestic Total 

Distance Domestic Well Groundwater 

(Miles) Wells Population Population 

0-1/4 0 0 0 

1/ 4-1/2 0 0 0 

1/2-1.0 0 0 0 

1.0-2.0 2 10 10 

2.0-3.0 0 0 0 

3.0-4.0 0 0 0 

I TOTAL. I 2 I 10 I 10 I 

Source: Stanley 1995; Ellis 1995; Happe 1995 

The nearest well (with a well log) is located at Milepost 26 on Nabesna Road, 17 miles 

northwest of the site. Table 3-2 presents the stratigraphy of the area, and Appendix F 

contains the well log. 

6276019509.0651SECTION3 
AR000021

Nabesna Mine, 1\'. abes , Alaska Section 3.0 

Site Inspection Repo rt Page 3-2 

Table 3-2 

Stratigraphy 

I Dt' pth (in feet) I Composition I 

0 - 12 Grave l 

12 - 6S Gravel/ Sand 

6S - 73 Wet Sand 

73 - SI Gravel with Watc:r 

Soum;: USGS Water Resource Di~ision 1995 

3.2 SURFACE WATER PATHWAY 

The Nabesna site is located on the west side of the Nabesna River Valley. Cabin Creek 

is 0.25 mile southwest of the site and its flow is seasonally dependen t. Cabin Creek 

meanders, submerges, and re-emerges in places as it flows toward J ack Creek. Cabin 

Creek flows wi thin 0.25 mile of the lowe r tailings. There is evidence that the surface 

water (which is composed of either precipitation or the spring runoff of Cab in Creek) 

has eroded the lower tailings. Cabin Creek flows northeast of the mill to join Jack 

Cree k, \vhich flows approximately 5 miles to join the Nabesna River, which is fed from 

the Nabesna Glacier. The surface water pathway for 15 miles downstream of Nabesna is 

summarized in Table 3-3. 

Ta ble 3-3 

Description of Surface Wa ter 15 Miles Downstream 

Distance from S ite Fish Production per l ..\n l Average Flow 

Surface Water Body (miles) Rate (cfs) Year (lbs)

Cabin Crec:k 0 - -I 3 0

Jack Creek -I - 9 760 65

::i bes□ a River 9 - 15 6000 100

Source: Hoffman 1995; l'iat al Park Servi ce 199-1 

The net precipitation is 4.4 1 inches and the 2-year, 24-hour rainfall is 0.8 inch (U.S. 

Department of Commerce 1992). (See Appendix G .) 

62760\9509.065\SECTION3 
AR000022

Nabesna Mine, Nabesna, Alaska · Section 3.0 

Site Inspection Report Page 3-3 

The site is situated within the Wrangell-Saint Elias National Park and Preserve. Fishing 

occurs in Jack Creek and the Nabesna River for arctic gray[ing (Thymallu.s arcticu.s 

[Pallu.s ]). The Nabesna River is identified as a river with anadromous fish; Chum salmon 

(Oncorhynchu.s keta) and Coho salmon (Oncorhynchu.s kautch), however, are not found 

within the 15-mile section downgradient of the site (Hoffman 1995) (Wise 1995). 

A spring believed to be fed by Jack Creek is• located approximately 5 miles northeast of 

the site. This spring is being used by a resident in the area for drinking water 

(McGuinness 1995). 

3.3 SOIL EXPOSURE PATHWAY 

Currently, no one resides at Nabesna; however, during the summer months, geologists 

from the University of Miami stay in the cabins in the Nabesna mine ghost town and are 

involved with a geochemical study of the area. No day care facilities or schools are 

located within 200 feet of this site. The tundra is considered a sensitive terrestrial 

enyironrnent, and 6,250 acres of tundra are located within a 4-rnile radius. The site is 

situated within the boundaries of a national park and preserve. The nearest residents 

are located approximately 2 miles northeast of the site. There are approximately 10 

residents within 4 miles of Nabesna. 

Access to the site is unrestricted and the Alaska Department of Transportation has a 

right of way on the site. 

After the mining operations ceased over 50 years ago, and the process of using a cyanide 

leaching method to recover gold from the tailings in the 1980s was discontinued, little 

revegetation occurred; however, some vegetation is present on the tailings. This could 

possibly be due to the acidity of the tailings (pH 2-5) and the unsuitability of the 

substrate (NPS 1986). · 

3.4 AIR EXPOSURE PATHWAY 

The contaminants present at this site are inorganics, cyanide, and semivolatile organics 

compounds (SVOCs), some of which are readily released to the air. However, because 

operations at the site ceased iri the 1940s, releases to the atmosphere are expected to be 

negligible (i.e., only occur when the ground is disturbed by someone or something 

traveling across it). 

6276019509.065\SECTIONJ 
AR000023

Nabesoa Mine, Nabesoa, Alaska Section 3.0 

Site Inspection Report Page 3-4 

The peregrine falcon (Falco peregn·nus), which is federally listed as end angered, bas been 

observed migrating through the area within 4 miles of the site. 

The Wrangell-Saint Elias National Park and Preserve has the site within its boundaries. 

There are approximately 6,250 acres of tundra within a 4-mile radius of the site. There 

are 10 residents that live within a 4-mile radius of the site (T able 3-4). 

Table 3-4 

Residents and ·w etland Acreage within a 4~Mile Radius 

0 50 

0 100 

'/2-1 

0- 1⁄4 

0 500 

1-2 10 1,400 

2-3 0 1,700

3-4 0 2,500 

Total 10 6,250 

62760\9509.0651S ECTIONJ 
AR000024

Nabesna Mi.ne, Nabesna, Alaska Section -t.0 

Site Inspection Report Page +I 

4.0 SA.ivIPLING PROGRA.\1 

4.1 OBJECTIVES Al'iD SCOPE 

The field sampling conducted for this SI was intended to gather data about potential 

releases from this site to surface water. The sampling objectives for the Nabesna mine 

SI were to assess the (I) presence or absence of inorganic compounds, cyanide, 

pesticides, PCBs, and semivolatile organic compounds (SVOCs) in soil; and (2) assess 

the presence or absence of inorganic compounds and cyanide in the upper and lower 

tailings, surface wate r, and sediments. Samples were collected from the following 

locations: 

• Upstream Cabin Creek: surface water and sediment 

• Cabin Creek downstream of the mine tailings: surface water and sediment 

• Cabin Creek before confluence with Jack Creek: surface. wate r ahd 

sediment 

• J ack Creek before confluence with Cabin Creek: surface water and 

sediment 

• Jack Creek after confluence with Cabin Creek: surface water and 

sediment 

• Upper tailings: surface and subsurface soil 

• Lower tailings: surface and subsurface soil 

• Mill: soil samples 

• Background soil samples 

• Background mineralized soil sample-to compare 1,,vith tailings 

The environmental samples collected to accomplish these objectives are described in the 

next subsection. Soil samples were analyzed for inorganics, cyanide, pesticides, PCBs, 

and SVOC. Surface water samples were analyzed for inorganics, cyanide, and hardness. 

Field testing was done on surface water for pH, conductivity, and temper ature. Sediment 

samples were analyzed for inorganics and cyanide. 

The samples collected during the Nabesna field sampi.illg event are summarized in 

Table 4-1. Figure 4-1 illustrates the approximate locations of the on-site samples, and 

Figure 4-2 illustrates the approximate locations of the off-site samples. 

6276019509.065\SECTION-l 
AR000025

Nabesna Mine, Nahcsna, /\lask,1 Scction 4.0 

Site lnspctlion Report Pagc 4-2 

Table 4- l 

Sample Descriptions 

Sample IJatc / Time 

Matrix Numhcr Location Rationall· S11 111plc Coll1:l·kd 

Sedi111L:11t NMCSDO I Cabin Creek background sample.:, southwest, upgradient or the mi ll'. llat:kgruund <,/20/'J5 / 11 17 

NMCS002 Cabin Creck downgnidie 11l o f the mill, at thc sus pected probable point of Charactc rizc ~cd imcnts (1/2 I/'J.5 / I 1-1.'i 1..:nlry. 

NMJSD03 Jack C reek background sample, nort heast, upgradient of the mi ll. Uackg ruund r,/2 1/'>5 / 1x 1'J 

NMJS004 Jack C rcck, downg radie nt of the mill, below the conllue nce or Cabin Cree k Charactc ri1.e ~cdime nts r,;2 1/'JS / ns2 

and Jack Creek. 

NM.ISDOS D uplicate of J ack Creek, downgradient o f the mill, below the co nfluence of Quality assurance r1/2 1/'J5 / 1352 

Cabin Creek and J ack Creck (NMJSD04). 

NMCSD06 Cabin Crcek, downgrad ient of thc mill, before the conlllll:nce o f Jack Creek. Charat:ll:rize sedimc nts 6/21/95 / 13 14 

Tailings NMUTSSOl Uppcr tailings surface sample ... Cha racte rize soil 6/20/95 / 1541 

NM UTSl302 Uppe r tailings subsurface sampie Characlt:rize soil 6/20/95 / 1546 

NMUTSS03 Upper tailings s urface sample Characterize soil ri/20/95 / 1532 

NMUTSl304 Upper tailings s ubsurface sample Characterize ~oil 6/20/95 / 15<15 

NMLTSS05 Lower tailings surface Characterize soil <,;2 1/ 95 / 01

>28 

NM LTS UOG Lower tailings s ubsurLicc Characte rize soil <1/2 1/95 / 0949 

NMLTSS07 Lowe r tailings sur~acc Characterizc ~oil <1/2 1/95 / 1000 

NMLTS008 Lower tailings subsurface Charactai:te soil <,/2 1/ 1

>5 / 10 10 

NMLTSIJ15 Duplicate subsurface sample ( NMLTSU08) Ouality assurance c,;21/1

>5 / 1010 

Soil NMIJSS09 Northwest of the site surface soil Oackground <1/21/95 / 1824 

NM13S l310 Northwest of the sitc s ubsurface soil Background <,/2 1/95 / 1x10 

NMMSSll Surface soil sample around mill. Characte rize snil (, /20/95 / I (156 

NMMSS12 Surface:: soil sample around mill. Characterize ~nil (1/20/95 / 1454 

NMMSSl3 Surface:: soil sample around mill. Characterize sllil ri/20/'>5 / 1440 

62760\9509,(J(,5\1'1!1.A- 1 
AR000026

Nabc.sna Mine, Nabe.srw, Alaska Section 4.0 

Sile Ins pection Rcporl Page •l-1 

Table 4-1 (Continued) 

Sample Descriptions 

Sample 

Matrix Number 

Soil NMMSS14 

NMSSHi 

Waler NMCSWOl 

NMCSW02 

NMJSW03 

NMJSW04 

NMCSW05 

NMCSW06 

NMEROl 

Localion 

Duplicate surface .soil sample around mill (NMMSS 12). 

Soil sample, upgradienl of mine-used for comparison with tailings 

Cabin Creek background .sample, southwest, upgradicnt of the m ill. 

Cabin Creek downgradicnt of the .mill, al the suspected prob;iblc point nl' 

entry 

Jack Creek background .sample, northeast, upgradicnt of the mill. 

Jack Creek, downgradient of lhe mill, be low the confluence of Cabin Cn.:ek 

and Jack Creek. 

Duplicate of Cabin Creek downgradicnl of the mill, al lhc .suspected 

probable point of entry (NMCSW02). ' • 

Cabin Creek downgradienl of the mill, before the confluence o f Jack Crtek. 

Equipment rin.salc 

Rationale 

O ual ity assurance 

13 ackgrnund mine ralize d so il 

Background 

Characterize wat er 

Background 

Characte rize waler 

() u;dity assura nce 

Charactc rizc water 

Ouality assurance 

Date/ Time 

Sa rn plt• Collected 

(l/20/ '!5 / 152 1 

(l/20/95 / 1150 

(i/20/ ')5 / 11 1() 

(l /2 I/'!.", / I I 14 

(l/2 1/ ')5 / 18 10 

()/ 21 /'JS / 134] 

(,/2 1/')5 / I 1,15 

6/2 1/ '!5 / 1106 

<)/ 20/<JS / 1755 

62760\9509.065\TBlA-I 
-,-

~ .

◊- l J /) r ( ( ; '-! / ( \ 1 I / i ! I\ : \ \ J , I i I 

' I / / / /

1 3900 \ / / l / I / / 

/ \ 3800 3700 3600 3 6cJ ( j I /! t 

~-j J I 3~00 3~60 I i 

/ I/ '- 1 / I 3~00 / J

J '-',,.}~ I I I

I / ,)lO(( 

,/ I 

,, I ,,, 30~0 , / ,', , I 

/ \'j / / : / I

1 -

/ l-->z - I I I 1 I

I ' _,,/ 

, , 

/ --~%---✓ I J I /I .,.,., / -

..ol' - ;' I / ' , 

I 

I 'j, \ / . I / j 

I I I I ,,,.,, ' , I \ ....., / '' i ' ,, //',\' II ! / I 

I 

I ,,,......,/· ___,/,,,.,.....~•- '-:\___/ / ~ Upper Tailings 

~ ,-------'-, 

/ / / / , 

t ,

' ', NMMSS13 , ,,. ...')<,> -'.i:t,,',<,< .

----

,~--- -:::, -----..,,..,,, ' __..,,,,,. ·-, 

/ ', ... 

/ ,,, / , e4'.,,,ilb,,,•.¥f,•i ,, t",,."<,s:,,.,.,1.-" •'-"-• "'1, /,,. ,_.,/ ', ◊ MIii A11llrllnn,•!', ,L,h-ft<' """•~"~"" • Lower Tailings ,,/ / ,,----- / 

-~-,.. 

1 

~ . 

'/ 

~ 

/ r.hnc: 

~ InI

I 1/ _e 2800 '/ ----- ......... ;' ' ' ...... / / /J I/r&•,-~ . !,-~.-. 

-- ,, "· ,:,-' ' ,. .

·•.·;,' ... '';·; 

/,,. _-N;;sna Mineif/ /V)J ~ ~~~iM.·LT.S·•.·S05 :· . ·,''.~)\· ~~; , /INML.TSB06 · · ;_; ,..... /

1:) \ '• ··•.·. ··: - _. I 

'11 \ . · •···• ,. ---- I 

- V ~/. 

_ / V" 

Go 

~ / 

·~,"' .. ______ NMLTSS07 --·-·- /

• Soil Sample Locations \ , "' NMLTSB08 I EB Sediment Sample Locations NMUTSS01 7 ,,i1 I NMLTS015 i ;E' I I CD Tailings Sample Locations NMUTSB02 \ 

0 Water Sample Locations J\ I ; 

+ 

QA/QC Sample \ I ; \ 

Drawing Nol lo Scale NMER01 \

NORTH \ \ J

Source: National Park Service, 1994 \ \ 

URS Figure 4-1 Nabesna Mine

Nnbcsna, Alaska On-Site Sampling Locations CONSULTANTS SITE INSPECTION

416276035-1·11::095 
·

!/>.~ 7'·r.r;::::,-;,_,·-:. ................) _---"'-". -----;,-- ---;::-<~\ "\ ·1·( " ---~~~~--/~ 

, l_l/J ---::-----~~ ",_;-· '__,,.-:., ./,-- • ' --· I ', ~- 12 J -

_:,, ~ I / 

t~rOR --- -~ ......[.qAit__ / '"'.

---- -- " . ---_:;:,-,_ -" 

+------ 1/-ta: Reeve I 

', Field 

' 

• Soil Sample Locations 

EB Sediment Sample Locations 1:.. 0 Water Sample Locations 

I·•! i, 

NORTH Scale in Miles 

'Source: USGS 1960, Nabesna Quad .A " 

;; 

" 

URS Figure 4-2 Nabesna Mine

N;ihcsna, Alaska Off-Site Sampling Locations COMSULTANTS SITE INSPECTION

• 1627603!,-J-091895 
AR000029

j\;abc:sna Mine, Nabesna, AJaska Section -4.0 

Site Inspection Report Page + 6 

-t2 SA1vlPLING METHODS 

The media-specific procedures used during the field sampling conducted at the Nabesna 

site were consistent with me thodologies described in the Quality /vfanagement Plan 

(QMP) (URS 1990a) and Technical Standard Operating Procedures (TSOP) for the 

Alternative Remedial Contracts Strategy activity (URS 1990b), as well as those described 

in EPA's Compendium of Superfund Field Operations Methods (U.S. EPA 1987). All 

sampling equipment was decontaminated prior to and following use. 

4.2.1 Surface Soil 

Surface soil samples were collected to document the presence or absence of hazardous 

substances in soil and to assess whether past s.ite practices impacted on-site soil quality. 

Surface samples were collected at depths ranging from Oto 6 inches bgs at four locations 

around the mill area. An additional surface soil sample was collected off site to 

characterize background conditions. I 

4.2.2 Surface Tailings 

Surface tailing samples were collected to document the presence or absence of hazardous 

substances in surface tailings and to assess whether the waste produced from the mining 

process could potentially impact on-site soils, surface water, and groundwater. Surface 

samples were collected at depths ranging from O to 6 inches bgs at two locations in the 

upper tailings area and two locations in the lower tailings area, whe re wastes were 

suspected to have been placed. 

4.2.3 Subsurface Tailings 

Subsurface tailing samples were colle cted to document the presence or absence of 

hazardous substances in subsurface tailings and to assess whethe r the waste produced 

from the mining process could potentially impact on-site soils, surface wate r, and 

groundwater. Subsurface samples were taken from two locations in the upper tailings 

area and two locations in the lower tailings area. These samples were collected directly 

below the locations where the surface tailings samples were taken, at depths ranging 

from 18 to 24 inches. The tailings samples were collected using a decontaminated 

trowel. 

4.2.4 Surface Water 

Surface water samples were collected to document the presence or absence of hazardous 

substances in surface water and to assess the potential release o'f contaminants to Cabin 

6276019509.065\SECTION4 
AR000030

j\;abesna Mine, Nabesna, Alaska Section -LO 

Sile Inspeclion Report Page+7 

and Jack creeks. Surface water samples were collected prior to the collection of 

sediment samples. At the time of sample collection, the pH, conductivity, and 

temperature of the water body was noted. 

4.2.5 Sediment 

Sediments were collected to document the presence or absence of hazardous substances 

in Cabin Creek and Jack Creek. All sediment samples \Ve re collected as grab samples 

and co-located \Vi th surface water samples. The .sediment was taken fro m the creek 

bottom. When encountered, sticks, rocks, and other large organic matte r were removed. 

Sediment samples were collected as close as possible to an area of sediment deposition. 

4.3 Ai'\/ALYTICAL AND HANDLING REQUIREMENTS 

Region IO EPA chain-of-custody procedures were followed in accordance with 

requirements ou tlined in URS's TSOP (URS 1990b) and QMP (URS 1990a). Due to 

the potential evidentiary nature of the data collected during this project, all samples 

intended for analysis in the EPA Region IO laboratory were handled and documented in 

accordance with procedures specified in EPA's User's Guide to the Contract L aboratory 

Program (U.S. EPA 1991), URS' QMP (URS 1990a), and National Enforcement 

Investigations Center Policies and Procedures (U.S. EPA 1985). Sample packaging 

conformed with applicable Department of Transportation regulations (49 CFR 171-177). 

6276019509.065\SECTION4 
AR000031

NJbesnJ Mine, Nabesna, Alasb Section 5.0 

Site Inspection Report Page 5-1 

5.0 SAMPLE RESULTS A..t"1D DISCUSSION 

The conditions used to define an "observed release" of a particular substance to any of 

the matrices sampled during the data evaluation process are summarized in Table 5-1 

(U.S. EPA 1990). When data results are discussed in this report, the term "significant" is 

used to classify concentrations of detected chemicals based on the criteria described in 

Table 5-1. The results discussed in the following subsections are limited to those 

concentrations of substances dete rmined to be significant (as defined in Table 5-1 ). 

Table 5-1 

Significance Criteria fo.~. Chemical Ana lysis 

Sample Measurement < Sample Quantitation Limit• 

No observed re lease is establish~d, the result is not ide ntified as "significant" 

Sample Measurement ~ Sample Quantitation Limir' 

An observed release or "significant" result is established as follows: 

If the background concentration is not detected (or is less than the detection limit), a n 

observed re lease or significant result is established when the sample measurement equals or 

exceeds the sample quantitation limit3 

• 

If the background concentration equals or exceeds the detection limit, an observed release or 

significant result is established when the sample measurement is three times or more above 

the background concentration. 

3 If the SQL cannot be established, detennine if there is an observed release as follows: If the sample 

analysis was performed unde r the EPA CLP, use the EPA CRQL in place of the SQL. If the sample 

analysis was not performed under the EPA CLP, use the DL in place of the SOL. 

Source: U.S. EPA 1993 

According to EPA Region 10 policy, aluminum, calcium, iron, magnesium, potassium, 

sodium, and zinc ( common earth crust metals) generally are employed only in water 

mass tracing, which is beyond the scope of this report Therefore, the results of the 

analysis of these analytes will be included but not discussed. 

The tables in this section include all reported concentrations of compounds or analytes 

detected in at least one sample collected during the June 20 and 21, 1995, sampling 

event. Appendix H includes the laboratory data results and data validation reports, as 

well as a summary table of the target and actual data quality objectives of the N abesna 

field sampling. 

6276019509.065\SECTIONS 
AR000032

Oosite Soil 

around Mill 

Onsite Soil Onsite Soil Area Onsite Soil 

Background around Mill around Mill - NMMSS14 , around Mill 

Soil Area - :. Area (Duplicate of Area 

NMBSS09 NMMSSll NM.MSS12 Nr.-LVISS12) NMMSS13 

Compound (μg/kg) (μg/kg) (μg/kg) (μg/kg) (μg/kg) 

2-Methylphenol 207 U 151 U 166 J 522 U 214 U 

4-Methylphenol 13.5 J 151 U 364 322 J 214 U 

4-Ni troaniline 1,030 U 756 U 1,400 U 273 J 1,070 U 

Benzoic acid 8,Ui0 U 6,050 U 9,700 J 13,300 J 8,560 U 

Benzyl alcohol 207 U 151 U 563 529 214 U 

Fluoranthene 207 U 151 U 279 U 18.1 J 214 U 

Isophorone 207 U 151 U 279 U 522 U Ui.4 J 

Napthalene, 2-methyl 207 U 18.0 J 279 U 522 U 214 U 

Phenol 20.9 J 151 U 304 369 J 3-t2 J 

Notes: 

J Value is an estimate 

u Sample was not detected; value shown is the quantitatioo limit 

UJ Analyte was not detected above the reported sample quantitation limit; the reported 

quantitatioa limit is an estimate. 

Nabesna Mine, Nabesna, Alaska Section 5.0 

Site Inspection Report Page 5-2 

5.1 SOIL SAJ\1PLE RESULTS 

Soil data results that satisfy the criteria listed in Table 5-1 are highlighted in Tables 5-2, 

5-3, and 5-4. Soil samples collected during this investigation were analyzed for SVOCs, 

PCBs, pesticides, inorganics, and cyanide as described in the field sampling plan (URS 

1995). No information was available in the data validation reports to assign a bias (high 

or low) to the qualified (''J") sample results identified in the tables. 

5.1.1 SVOC Analyses 

SVOCs detected in the surface soil samples collected on site are summarized in 

Table 5-2. 

Table s·-2 

Semivolatile Organic Compounds in Surface Soil 

6276019509.065\SECTIONS 
AR000033

-- ---

·•

Aluminum I 11,000 12,10() 1,930 1,760 2,490 9,660 

----t--~(\;:-..,=-:...,~.- --t--- -::-,.-::-,.-:-,-::-,--+----:6:-:.9:--=2-:J,-----t,, Arsenic 9.32 J 6.64 J 

Barium 190 238 19.5 32.1 66.9 47.5 

Beryllium 0.32 J 0.35 J 0.25 u o.5 u I o.5 u I 0.16 1 

--,------+-------+-------+-------1,,,,,,,,,,,,,,.,,,,.,..,,..,,. Cadmium 0.21 ,.. .... J • 0.21 ,.. .... J• 1.0 u :r::}:rtm:J/§.\$::JJtr=: t(>?i':=,=><,: u~μ :.J·t>,< ::i 1.26 

Calcium 9,200 ~ ~ M 13,200 290,000 1,870 3,020 28,000

Chromium- 23.5 ~- ~ -~ 23.4 . 7.4 J 62.5

Cobalt 11.0 12.4 5.0U .l2J 8.3 L 

Iron 23,500 25,400 4,no I 329,000 I · 263,ooo I 20,.500 

Lead 7.38 5.36 

Magnesium 9,450 10,400 5,040 724 1,220 5,()00 

Manganese 443 509 145 . I 449 I 525 I 611 

Mercury 0.0692 0.153

Nickel 26.3 27.4

Potassium 812 790 310 J

Silver 0-.

- . 34 J • 0.34 - - . J• 1.5 U -----+ Sodium 405 350 85.0

Vanadium 54.1 61.2 5.59 26.o I 25.6 I 30.1

Zinc 57.2 . 60.3 35.5 2,320 1,440 165

Selenium 0.45 J 0.44 J 0.4 U 0.6 U 2.6 J 0.4 U

Cyanide 0.33 U 0.33 U 0.28 U 1rtittt:!JI~m1:r1:JtJ't:r 6.57 ··· ·•:,)\9.;1J}f'}:ftt:::J 

Notes: 

Bolded values represent significant concentrations 

J Value is an estimate 

U Sainplc was nol detected; value shown is the quantitation limit 

I 

Nabesna Mine, Nabesna, Alaska Section 5.0 

Sile Inspection Report Page 5-4 

Table 5-4 

Inorganics in Soils 

62760\9509.065\TBW-4 
AR000034

•

·,•,,• ,••' , .. _:; .. ..'. .. ... .. 

·••· Dow,igrudi~_nt 

Bnckt,,round : Cabin Creek Background 

• ;❖; r: : Sediment •· • 

.. . ·•·· Scdi~cnt~ ... •:-,' :,:·•·· 

. Soil<\ ... 

NMCSD0l · NMCSD02 NMBSS09 . 

Compound .. ' (μg/kg) '.' : (μg/kg) •. .(μg/kg) :.• ;. 

Onsitc Soil 

around Mill 

O~sitc Soil 

around Mill 

·:; ·Acen Arca 

NMl\1.SSU • NMMSS12 

•.) (μg/kg) •· • ' (μg/kg) 

Onsilc Soil 

around Mill 

Arca 

NMMSS14 

Duplicate of 

NMMSS12 

(1£g/kg) 

Onsite Soil 

a round Mill 

Arca 

NMMSS13 

(μg/ kg) 

Equimcnt. •· 

.. Rinsntc 

EROl 

(μg/L) 

Endrin 1.43 U 3.67 U 1.61 U 1.18 U 2.80 2.04 U 1.67 U I 0.00347 UJ I I I I I I I I I 

Notes: 

J Value is an estimate 

u Sample was not detected; value shown is the quantitation limit 

U.I Analyte was not detected above the reported sample quantitation limit; the reported quanlitation lirni1 is an es't imal e . 

Nabesna Mine, Nabesna, Alaska Section 5.0. 

Site ln.spection Report Page 5-3 

Table 5-3 

PCBs/Pesticides in Sediments, Soil, and Rinsatc 

6276019509.065\TBLl-3 
AR000035

Nabesaa Mine, Nabesna, Alaska Section 5.0 

Site Inspection Report Page 5-5 

• Background Soils-Two SVOCs were detected in the background sample 

(NMBSS09) at estimated concentrations. 

• On-Site Soils-Three compounds were detected in soil around the mill 

(NMMSS 12): 4-methylphenol, benzyl alcohol, phenol, and an estimated 

concentration of benzoic acid. 

5. 1.2 PCB Analyses 

No PCBs were detected in any of the surface soil samples collected on site during the 

Nabesna field sampling event. 

5.1.3 Pesticide Analyses 

Pesticides detected in the soil samples collected around the mil1 are summarized in 

Table 5-3. 

• Background Soils-Pesticides were not detected in the background sample 

(NMBSS09). 

• On-Site Soils- Endrin was detected in soil sample NMMSS12, at a concentration 

of 2.80 μg/kg. 

5.1.4 Inorganic Analyses 

Inorganic analytes detected in surface soil samples collected on site are provided in 

Table 5-4. (Those inorganics detected at significant concentrations are highlighted.) 

• Background Soils- Inorganics were detected in the background surface soil 

sample (NMBSS09), and the background subsurface soil sample (NMBSBlO). 

• On-Site Soils-Seven inorganic analytes were detected at concentrations elevated 

above background: arsenic (NMMSS12, NMMSS13, and NMMSS14), cadmium 

(NMMSS12 and NMMSS14), chromium (NMMSS12 and NMMSS13), lead 

(NMMSSll, ~MMSS12, NMMSS13, and NMMSS14), mercury (NMMSSll, 

NMMSS12, NMMSS13, and NMMSS14), nickel (NMMSS12), and silver 

(NMMSS12, NMMSS13, and NMMSS14). The soil samples were collected from 

the area surrounding the mill (Figure 4-1). 

6276019509.065\SECTIONS 
AR000036

i'iabesaa Mine, Nabesaa, Alaska Sect.ion 5.0 

Site Inspection Repo rt Page 5-6 

5. 1.5 Cyanide Analyses 

Cyanide detected in the surface soil samples collected on site are summarized in 

Table 5-4. (Those inorganics detected at significan t concentrations are highlighted.) 

Background So ils-Cyanide was not detected in the background soil sample . • 

On Site Soils-Analytical results of three soil samples collected from around the • 

mill revealed the presence of cyanide at significant concentrations (NMMSS 12, 

NMMSS 13, and NMMSS 14). 

SURFACE A.!'\/O SUBSURFACE MINE;TAILINGS 

Data that satisfy the criteria listed in Table 5-1 are highlighted in Table 5-5. The surface 

and subsurface tailings samples collected during this investigation were ana,lyzed for 

inorganics and cyanide as described in the field sampling plan (URS 1995). No 

information was available in the data validation reports to assign a bias (high or low) to 

the qualified ("J") sample results indicated in the tables. 

5.2.1 Inorganic Ana lyses of Mine Tailings 

Inorganic analytes detected in upper and lower surface and subsurface mine tailings are 

listed in Table 5-5. (Those inorganics detected at significant concentrations are 

highlighted.) 

• Background Mineralized Soils-Inorganics were detected in the background 

mineralized soil sample (NMSS 16). The background mineralized soil sample is 

more representative of the crushed ore that the tailings would consist of than the 

background soil sample. 

• Upper Tailing Soil Samples-Five inorganics were detected in both the surface 

and subsurface mine tailings at concentrations above background: arsenic 

(NMUTSSOl, NMUTSB02, NMUTSS03, and NMUTSB04), cadmium 

(NMUTSSO l), lead (NMUTSS03), mercury (NMlJ fSS_O l, NMUTSB02, and 

NMUTSS03), and thallium (NMUTSS03). 

• Lower Tailing Soil Samples-Seven inorganics were detected in both the surface 

and subsurface mine tailings at concentrations above background: arsenic 

();\fLTSS05, NMLTSB06, N\fLTSS07, and N~fLTSBOS), cadmium (1 MLTSS05, 

NMLTSS07, and NMLTSBOS), chromium (NMLTSBOS), cobalt (NMLTSS06), 

6176019509.0651SECTION5 
AR000037

Nabcsna Mine, Nabcsna, Alaska Scction 5.0 

Site Inspection Report Page 5-7 

Table 5-5 

Inorganics in Tailings 

Aluminum 1,860 1.560 I 2,210 I 411 I 3,180 I 1 ,460 I 2,110 I 1,r,10 I 2,r,90 l 2.,1?0 

Arsenic 21.1 J 

Darium 24S 

Cadmium 8.6 J 

Calcium 13,000 

Chromium 6.9 J 

Cobalt 19 J 

Iron 211,000 

Lead 44.0 J 

Magnesium 3,190 

Manganese 1,070 

Mercury 0.14 

Nickel 10 U 

Potassium 930 J 

Silver 109 

Sodium 112 

Vanadium 23S 

Zinc 2,200 

Selenium 28.7 

Thallium 0.75 U 

Cyanide 0.33 U 

MJ?i9i!79H'tt:m t/t}/1~!:t:JtJ' 'j)J:J:t,Qt@t1lf i:]'lil?:AAt:JtH JJ+::mi1~tw:nw·J@l::~1~) {:. {\J,3~o:n :\;'(_1;1,10,)'\; 

3.64 20.2 4.76 59.1 6.82 2.5 J 8.RS JOA 

nu::11 ~,~;,,trt1r 3.3 1 u 1 3.4 1 'J,J'tnrn:trt:t· s .2 1 1-':\:;:::1_, 

114,000 80,400 147,ooo 11,100 112,000 11,soo I 109.000 

3.2 J 4.0 J 3.6 J 

5.0 U 5.0 U 4.6 1 

96,200 94,200 42,700 

1,330 825 :'}':,,?~~in~E'.22 

594 795 320 

141 I 98.5 I 65.4 

;;;::,:;;;;::::;;:;f ~;~t;;;;;;•;;;:;;;T;::::;;;;;::?:;~~~:;;;;; ,:;:: ;;:: lt\:::rr~~:::;::;;;;: :/:: 

470 1 380 J 479 

36,7 20.8 73.8 

68.6 413 101 

14.8 19.1 5.89 

225 152 139 

3.43 2.47 10.6 

0.25 u I 0.25 u l:'':?:::::::::'.}9'.~+·+f" 

:;:::nrw:mnt@::m:1annn:rn~4§.::rnmrrrrnnr::rm1t:m;:e:1:, 

7.6 J 

7.0 1 

106,000 

57 

1,700 

71.8 

0.105 . 

5.0 U 

740 J 

2.2 J 

2,250 

39.0 

107 

1.6 J 

0.25 U 

0.47 U 

5.0 U I 2.s 2..5 u U Lt qw::;, 

k>, >n ;:::::-. I 9.4 J I 21 J .o.:~.n::t 9.4 J 

157,000 I. ··: 125,000 67,300 

1,040 I 163 I 939 

1,050 I 2,230 920 

210 I 265 I --- 187 

1r::/J·~g~~;:;m:,,w,:t?rn:n::o.;~9:i:i:\i::H1··ttH;:;-~>:Yt Itn. -~:~tH? 

450 u I 450 u 890 J 620 J 

24.8 I 1.4 1 19.8 18.6 

111 I 37 1 205 92.4 

f65 I 18A 17.3 16.8 

1,600 I 942 661 2,070 

7.49 I 5.77 9.34 5.08 

o.94 -1 I o.57 1 ;)',:?!H\·lt/•\• I 0.15 u 

o.32 u T - o.30 u o.33 u I({? .Q.1~\}t 

5.1 J 

20 J 

145.000 

788 

2,390 

208 

0.897 

10 U 

450 U 

17.5 

71 J 

15.6 

1,%0 

3.97 

0.'15 J 

0.35 U 

Notes: 

Bo lded values represent significant concentratio ns 

J Val ue is an estimate 

U Sample was not detected; value shown is the quantitation limit 

62760\9509.065\TBW-5 
AR000038

Nabesna Mine, Nabesna, AJaska Section 5.0 

Site Inspection Report Page 5-8 

mercury (:-JML TSS05, NMLTSB06, and NMLTSS07), nickel (NMLTSB08), and 

thallium (NMLTSS07). However, nickel was not detected in the duplicate sample 

(~MLTSB16) of sample NMLTSB08. 

5.2.2 Cyanide Analyses for :\1ine Tailings 

Surface and subsurface samples of the upper-and lower mine tailings revealed the 

presence of cyanide. A summary of sample results is found in Table 5-5. Concentrations 

considered significant are highlighted. 

• Upper Tailing Samples-Cyanide was detected in three mine tailing samples 

(NMUTSS0l, NMUTSB02, and NMUTSS02) . 

.: . 

• Lower Tailing Samples-Cyanide was detected in one tailing sample 

(NMLTSB08); however, cyanide was not detected in the duplicate sample 

(NMLT15). 

5.3 . SURFACE WATER SAMPLE RESULTS 

Surface water data results that satisfy the criteria listed in Table 5-1 are highlighted in 

Tables 5-6 and 5-7. Surface water samples collected during this investigation were 

analyzed for cyanide, inorganics, hardness, conductivity, temperature, and pH, as 

described in the field sampling plan (URS 1995). No information was available in the 

data validation reports to assign a bias (high or low) to the qualified ("J") sample results 

identified in the tables. 

5.3.1 Inorganic Analyses 

Inorganics detected in the surface water samples for Cabin Creek and Jack Creek are 

summarized in Table 5-6. (Those inorganics detected at significant concentrations are 

highlighted.) 

• Background Surface Water- Inorganics were detected in the background surface 

water samples for Cabin Creek (NMCSW0l) and Jack Creek (NMJSW03). 

• Downgradient Surface Water- The following inorganics were detected in the 

downgradient samples for Cabin Creek (NMCSW02) and duplica te sample 

(NMCSW05): arsenic, barium, manganese, and zinc. Arsenic was detected in the 

downgradient sample (NMJSW04) for Jack Creek. 

6276019509.0651SECTION5 
AR000039

:

Arsenic 1.0 U 

Barium 2.8 J 

Calcium 6,380 

Iron 123 

Lead 0.52 J 

Magnesium 1,190 

Manganese 5.87 

Potassium 1,200 J 

Sodium . 1,810 

Vanadium 3.0 J 

Zinc 4.0 U 

245 20 U 23 J 

=''?''?'t???'''?e..1.:'??2 ??ff<'''t'J??===:g;7.§ ?@''?'(?<'I 

•?:t:ttIJ}!1~n::m:t::Jt@:=t!'t:::::rn:m:::r4ffe:~i=:r::w=:::r]::=I 

63,300 I 63,100 

2,660 I 2,620 

1.2 J I o.5 u 

8,130 I 8,220 

1:::mt:N::::m;t:M~:m::mr::::;rr:::ae=::m::]::::=tt::~;J::;::::::nm::rnJ: 

1,800 1 I 1,500 1 

3,540 ,-- 3,630 

3.o u I 3.0 u 

•:r:=::tm::;:::::::::1~,:::J,:::::::•::rn::::\rn%1•::::::=:::::=:=•=:=rn:::::::~s•:•~=•t:]•m:::•:•1:••1 

- I ... -- 42J 40 J 72 J 

3.6 J 1.0 U 

4.3 J 31.1 21.8 

63,500 45,800 43,900

81.1 99.5 67.0

0.5 l!.. 0.5 U 0.5 U

11,700 11 ,400 10,1()()

7.18 6.04 ll.9

1,700 J 2,030 J 1,800 J

4,350 5,190 4,940

3.4 J 3.0 U 3.0 U

4.0 U 4.0 U 4.0 U

. •·'• . -.• -

Nabesna Mine, Nabesna, Alaska Section 5.0 

Site Inspection Report Page 5-9 

Table 5-6 

Inorganics in Surface Water 

Notes: 

Balded values represent significant concentrations 

J Value is an estimate 

U Sample was not detected; value shown is the quantitation limit 

6276019509.065\TBl..5-6 
AR000040

Nabesna Mine, Nabesna, Alaska Section 5.0 

Site Inspection Report Page 5-10 

Table 5-7 

Surface Water Properties 

Sample Number 

Hardness 

(mg/L) 

Conductivity 

· (siemen.s/cm) 

Temperature 

(OF) pH 

!','Jv1CSW01 

Background 

Cabin Creek 

21.6 ·:69.4 66.8 8.20 

NMCSW02 

Downgrad.ient 

Cabin Cree k 

195.3 440.0 55 7.76 

NMJSW03 

Background 

Jack Creek 

161.6 _)24.0 60.4 8.39 

NMJSW04 

Dov.'Il.grad.ient 

Jack Creek 

149.5 

' 

289.0 58.5 8.39 

.NMCSW05 

Cabin Creek 

Duplicate 

191.9 440.0 55 7.76 

NMCSW06 

D o \l,'Il.gTa die n t 

Cabin Creek Before 

Jack Creek 

206.5 366.0 58.3 7.96 

5.3.2 Cyanide Analysis 

• • Background Surface Water-Cyanide was not detected in the background surlace 

water sample for Cabin Creek (NMCSWOl) or Jack Creek (NMJSW03). 

• Downgradient Surface Water-Cyanide was not detected in the downgradient 

samples taken from Cabin Creek or Jack Creek. 

5.3.3 Hardness Analysis 

• Surface Water- Surface water properties such as hardness, conductivity, 

temperature and pH were measured and presented in Table 5-7. 

62760\9509.065\SECTION5 
AR000041

N:ibesna Mine, Nabc:sna, AlJska Section 5.0 

Site Inspection Rc:port Page 5-11 

As the surface water passes through the mineralized soils and rock, its ability to 

act as a universal solvent with the inorganics it comes in contact with will increase 

the amount of particles that are held in suspension or dissolyed in the water. 

Increased levels of iron and manganese will increase the hardness and 

conductivity and lower the pH of the surface water. 

5.4 SEDIMENT SAMPLE RESULTS 

Sediment data results that satisfy the criteria listed in Table 5-1 are highlighted in 

Tables 5-3, 5-6, a nd 5-7. Sediment samples collected during this investigation were 

analyzed for SVOCs, PCBs, pesticides, cyanide, and inorganics as described in the field 

sampling plan (URS 1995). 

5.4.1 SVOC Analyses 

No significant concentrations 'of SVOCs were detected in surface water sediments, the 

concentrations are presented in Table 5-8. 

Table 5-8 

Semivolatile Organic Compounds in Sediments 

Ba ckground Sediments Downgradient Cabin Creek Sediments 

NMCSD0l NMCSD02 

Compound (μg/kg) (μg/kg) 

2,4-Dimethylphe nol 183 U 22.6 J 

2-Methylphe nol 183 U 53.8 J 

4-Methylphe nol 183 U 34.1 J 

Isophorone 183 U 23.0 J 

Naphthalene, 2-methyl 183 U 68.7 J 

Notes: 

J Value is aa estimate 

u Sample was not detected; value shown is the quaatitation limit 

UJ Analyte was not de tected above the reported sample quaatitation limit; the reported 

quantitation limit is an estimate. 

• Bac~oround Surface \Yater Sediment-SVOCs were not detected in the 

upgradient surface water sediment sample collected at Cabin Creek (NMCSD0l). 

6276019509.0651SECTION5 
AR000042

Nabes a Mine, i'iabesna, AJasb Section 5.0 

Site Inspection Report Page 5- 12 

• Dom1gradient Su rface \-Vater Sediment-SVOCs were not detected in the 

downgradient surface wate r sediment sample (NMCSD02). 

5.4.2 PCB Analyses 

PCBs were not detected in the background or downgradient surface water sediment 

samples. 

5.4.3 Pesticide Analyses 

Pesticides were not detected in the background or downgradient surface water sediment 

samples. 

5.4.4 Inorgani c Analyses 

Inorganics detected in sediment samples are summarized in Table 5-9. (Those 

inorganics detected at significant concentrations are highligh ted.) 

• Background Surface Water Sediment- Inorganics were detected in the 

background sediment samples for Cabin Creek (NMCSD0l) and Jack Creek 

(NMJSD03). 

• Dom1gradient Surface Water Sediment-Three inorganics were detected in Cabin 

Creek sediments below the mine tailings (NMCSD02): arsenic, lead, and 

manganese. Eight inorganics were detected in Cabin Creek before the confluence 

of J ack Creek (NMCSD06): arsenic, cadmium, chromium, lead, manganese, 

mercury, silver, and selenium. Inorganics were not detected above background 

concentrations in the downgradient Jack Creek sample (NMJSD04) or in the 

duplicate sample (NMJSD0S). 

5.4.5 Cya nide Ana lysis 

• Bac1⁄2oround Surface Water Sediment-Cyanide was not detected in the 

background sediment samples for Cabin Creek (NMCSD0l) or Jack Creek 

(NMJSD03). 

• Do\,11gradient Surface Water Sed iment-Cyanide was not detected in 

dmrngradienr samples in Cabin Creek or J ack Creek (Table 5-9). 

62760\9509.065\SECTIONS 
AR000043

Nabe5na Mine, Nabesna, Alaska Section 5.0

Page 5-13 Sile Inspection Report 

Table 5-9 

Inorganics in Sediments 

Aluminum 3,760 2,960 5,380 10,300 8,550 7,850 

Arsenic 1.29 lilir i::1:::n:mm:J@M;1J@tli\:'I} 4.57 3.47 3.53 

Barium 19.2 37.6 37.6 138 86.2 76.8 

Beryllium I 0.11 J I 0.068 J I 0.16 J I 0.33 J I 0.29 J I 0.28 

Cadmium I 0.2 u I 0.71 J 1t1:1::tJJ 9/~3::mrmt:r:tf}I 0.23 J 

Calcium I 5,060 I 4,250 I 11,600 ~12,800 

0.2l J 0.2 U 

15,600 20,1 00 

Chromi_um I 4.1 I 1.6 J t]J::=J::r::::::::!e~:::r::::?]1]1\ I 20.6 

Cobalt I 3.3 l 6.41 ·· I 7.05 I 9.86 

1'1.5 43.8 

8.28 8.01 

Copper I 10.8 . I 12.9 I 26.0 I 32.2 25.0 .. 24.2 

Iron I . 6,630 I 18,500 I 11,500 l~ 21,600 17,000 15,800 

Lead I 1.04 l::=i:::r:::::::::rw:;::m;.M:::::::i:mmn:::m:::J::::a:::::::::·rrr:u ~w>m::=wrrn::::::::j 2-

00 

Magnesium 1,380 1,060 4,310 8,810 

Manganese 129 MM%ttr:w@.9:Q.]t%FWlt'= ~~~~4----,--44_9____-+---,--,----~--4 

Mercury 0.02 U 0.02 U 1%{f{}ff9L.~!f.Hl1\':J]/ 0.047 - h--- Nickel I · 5.54 I 4.2 J I 11.9 I 25.1 

3.03 2.21 

8,290 11, too 

456 432 

0.0376 0.0301 

19.0 37.1 

Potassium 200 J 170 J 608 590 485 

I Silver 0.3 U 0.38 J 0.3 J - ·- -

Sodium 420 290 323 ·--

0.3 U 0.39 J 

407 351 

Vanadium I 22.5 I 17.7 I 37.1 I 50.5 43.1 38.2 

Zinc I 15.6 1 I 72.3 I 57.3 I 52.3 42.7 39.4 

Selenium I 0.2 U I 0.2 U l::=::::==:::: ::rn=@t@~:f@?Jtrnrn:::=::::u 0.33 J 0.25 J 0.2 J 

Notes: 

Bolded values represent significant concentrations 

J Value is an eslimale 

U Sample was nol detected; value shown is lhe quanlilalion limit 

62760\9509.065\TBW-9 
AR000044

Nabesoa Mine,_Nabesoa, Alaska Section 5.0 

Site Inspection Report Page 5-14 

5.5 J;'\'VESTIGATION-DERIVED WASTE 

No investigative-derived wastes were generated during this field sampling event. 

5.6 QUALITY COJ\1TROL SAMPLES 

During the fie ld sampling event, an equipment rins ate sample (NMER0l) was collected, 

the results for which are provided in Table 5-10. The equipment rinsate sample was 

collected after the stainless-steel hand auger was decontamina ted following the collection 

of the lower tailing subsurface sample (NMLTSB15). The detected compounds in the 

rinsate sample were butylbenzylphthalate and n-nitrosodiphenylamine. 

The quality control samples also included laboratory method blanks that contained 

detectable concentrations of the compounds listed in Table 5-1. 

None of these compounds were detected in the environmental samples. These results 

have not affected the quality of the data. 

Duplicate samples of soil, sediment, tailings, and surface water were collected to verify 

analytical precision. Due to the heterogeneity of soil, sediment, and tailings, the relative 

percent differences (RPDs) for duplicate sample results of these media are expected to 

exceed 35 percent routinely. RPDs for results within 5 times the reporting limit are 

considered unusable. RPDs for results when one or both are qualified as estimated are 

unreliable. Soil field duplicate results for metals have higher variability than that 

nonnally expected (40 to 45 percent), but because the laboratory duplicate samples and 

other quality control samples are within EPA guidelines, it is likely that the difference in 

results is the result of differences in soil metals concentrations over short distances. 

5.7 SUMMARY 

Analytical results of samples collected from the Nabesna mine site revealed the presence 

of contaminants in tailings, sediment, and soil. Significant concentrations of inorganics 

were detected in sediment, soil, and tailings samples. Concentrations of semivolatiles 

were detected in soil samples. Significant concentrations of cyanide in the subsurface 

lower tailings might indicate the presence of the cyanide that was used in the early 

mining activities. Significant concentrations of cyanide in the upper tailings might 

indicate the presence of the cyanide tha t was used in the cyanide leaching activities 

occurring in the 1980s. Table 5-11 lists the media and location at which various 

contaminants are present in significant concentrations. 

6276019509.0651SECTION5 
AR000045

Nabesna Mi.oe, Nabesna, Alaska Section 6.0 

Site Inspection Report Page 6-2 

Spude, R., LS., Taylor Dan, Lappen Michael, 1984. Histon·c Stn1crures lnvemory: in 

Wrangell-Sr. Elias Narional Park and Preserve. 

United States Department of Commerce. 1992. Probable Maximum Precipitation and 

Rainfall-Frequency Data for Alaska. Data Report 92-11. Alaska State Climate 

Center. September 1992. 

United States Department of the Interior. 1978. Nmional Regisrer of Hisroric Places 

lnventory-Nominarion Fann 

United States Geological Society. 1995. Water Resource Division. Well logs. 

United States Environmental Protection Age~cy (U.S. EPA). 1991. User's Guide to the 

Contract Laboratory Program, Office of Etnergency and Remedial Response, 

Washington, D.C. January 1991. 

---. ·1987. A Compendiun( of Superfund Field Operations Methods, Office of 

Emergency and Remedial Response, EPA/ 540/ P-87 / 001. 

---. 1978. Development Document for Effluent Limitations Guidelines and New 

Source Perfonnance Standards for the Ore /1,,Jining and Dressing Point Source 

Category, Volume I. PB-286 520. Effluent Guidelines Division, Office of Water 

and Hazardous Materials. Washington D.C. July 1978. · 

Yersar Inc. 1986. Quantities of Cyanide-Bearing and Acid-Generating Wastes Generated 

by the 1v!ining and Beneficiating Industries, and the Potential for Contaminant 

Release. Prepared for the U.S. Environmental Protection Agency. June 27, 1986. 

URS Consultants, Inc. (URS). 1995. Field Sampling Plan for the Nabesna Aline. 

Contract No. 68-W9-0054. 

---. 1990a. Quality lvfanagement Plan (QMP) for Alternative Remedial Contracting 

Strategy (ARCS), Contract No. 68-W9-0054. 

---. 1990b. Technical Standard Operating Procedures (TSOP) for rl.RCS; Contract No. 

68-W9-0054. 

Wayland, R. 1943. Geology of the Nutzotin Mountains, Alaska, and Cold Deposits Near 

Nabesna. Geological Survey Bulletin 933-B. 

6276019509.0651SECTION6 . 
AR000046

Nabesna Mi.ne, Nabesna, Alaska Section 6.0 

Site Inspection Report Page 6-1 

6.0 REFERENCES 

Brooks, H.C. and L. Ramp. 1968. State of Oregon Department of G eology and Mineral 

Industries. Bulletin 61. 

Ellis, L. (Owner of Devil's Mr. Lodge). 1995. Personal communication with Rebecca 

Juul, URS Consultants, Inc., Seattle, Washington, re: Nabesna, Alaska. 

June20-21 , 1995. 

Habashi, F. 1967. Kinetics and i'vfecfzanism of Cold and Silver Dissolution in Cyanide 

Solution. Montana Bureau of Mines, G_eology Bulletin 59. Butte, Montana. ·. . 

Happe, P. (Environmental Specialist, National Park Service). 1995. Telephone 

conversation with Rebecca Juul, URS Consultants, Inc., Seattle, Washington, re: 

Nabesna Mine Site, Ai'aska. March 16, 1995. 

Hoffman, A (Biologist, Anchorage Fish and Game Department). 1995. Telephone 

conversation with Rebecca Juul, URS Consultants, Inc., Seattle, Washington, re: 

Nabesna Mine Site,.Alaska. March 22, 1995. 

McGuinness, S. (Ranger, Wragell Saint Elias National Park and Preserve). 1995 . . 

Telephone conversation with R ebecca Juul, URS Consultants, Inc., Seattle, 

Washington, re: Nabesna Mine. March 22, 1995. 

National Park Service (NPS). 1986. Environme ntal Assessment and Analysis, 1986 Plan 

of Operation. Nabesna Mine, Sunshine Lode Patented Claim. Alaska Regional 

Office. July 31, 1986. 

Saleeby, B. (Archeologist, U.S. Department of Interior National Park Service). 1995. 

Historic Structures Inventory in Wrangell-Saint Elias National Park and 

Preserve 1984. 

Smith, S.L. 1982. Cyanidation of Cold and Silver Ores and Laboratory Instructions. 

Stanley, K. (Owner of Ptarmigan Co. and the Nabesna Mine). 1995. Site visit 

conducted with sire O\rner and Kara Steward and Rebecca Juul of URS 

Consu!tJnts Inc., Seattle, Washington. June 20-2 1, 1995. 

6276019509.06S\SECTION6 
AR000047

Nabeso:i Mine Section 5.0 , Nabesna, A.1:iska 

Page 5-15 Site Inspection Report 

Table 5-10 

Semivol atile Organic Compounds and Inorganics 

in Equipment Rinsate and Laboratory Method Blanks 

Equipment Riosate Lab Blank 

N0!EROl BW5380 

Analyte (μg/L ) ... (μg/L) 

Aluminum 2-rn 1 NA 

Arsenic 1.0 U NA 

Barium 2.0 U NA 

Bis(2-ethylhexyl) ph thabtc 0.44 UJ 231 j 

B utylbenzylphthalate 43.4 J 0.0S9 J 

Cadmium 2.0 U NA 

Calcium 78.0 NA 

Chromium 5.0 U NA 

Cobalt 10 U NA 

Copper 6.S J NA 

Cyanide 0.005 U NA 

Diethylphthalate 0.44 UJ 0.044 J 

Endrin 0.00347 UJ NA 

Iron 26.S NA 

Lead 0.50 U NA 

Manganese 20 U NA 

Nickel 10 U NA 

n-Nitrosodiphenylam ioe 0.1 l J 0.56 U 

Potassium 670 J NA 

Silver 3.0 U NA 

Sodium 103 NA 

Thallium 1.0 U NA 

Vanadiu m 3.0 U NA 

Zinc 4.0 U NA 

Lab Blank 

BW5380 D 

(μg/L) 

NA 

NA 

NA 

0.59 U 

0.59 U 

NA 

NA 

NA 

NA 

NA 

NA 

0.59 U 

NA 

NA 

NA 

NA 

NA 

0.59 U 

NA 

NA 

NA 

NA 

NA 

NA 

Lab Blank 

S950630..\ 

(μg/L) 

2.0 U 

5.0 U 

0.20 U 

NA 

NA 

0.20 U 

1.30 

0.50 U 

1.0 U 

0.30 U 

NA 

NA 

NA 

1.0 U 

2.5 U 

0.10 U 

1.0 U 

NA 

45 U 

0.30 U 

3.2 J 

NA 

0.30 U 

0.40 U 

Notes: 

J Value is an estimate 

u Sample was not detected; value shown is the quantitalioo limit 

NA Not analyzed 

62760\95C<J.0651SECTION5 
AR000049

APPENDIX A 

PHOTOGRAPHIC LOG OF JUNE 20 AND 21, 1995 SITE VISIT 
AR000050
AR000051

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

ARCS 

Photograph Log 

Project/Site Name 

Nabesna Mine 

Film Type/Speed 

URS 

Consultants, Inc. 

Project Number 

4162760.35 

Camera Type 

Kodak 200 

Orientation 

w 

E 

SW 

SW 

w 

NE 

w 

w 

w 

' 

w 

s 

w 

w 

NE 

SW 

DCN # 

62760.35.20.10 1 l 

Photographer(s) 

Kara Steward 

Roll Number 

2 

Subject 

45.a 

Date 

6/28/95 Canon 

Frame 

l 

2 

3 

4 

Dat e 

6/21 /95 

6/21 /95 

6/2 1 /95 

6/2 1 /95 

6/21/95 

6/21/95 

6/21/95 

6/21 /95 

6/21/95 

6/21/95 

6/21/95 

6/21 /95 

6/21/95 

6/21/95 

6/21/95 

Time 

0900 

0910 

0911 

09 15 

09 15 

0915 

0950 

1005 

1045 

1050 

1148 

1205 

13 10 

1347 

1350 

White Hills from Nabesna Road 

Mill tailings runoff (NPS property) 

Tailings runoff 

Upper tailings. Panorama 1/2 

Upper tailings and mill. Panorama 2/2 

Tailings runoff from upper area 

Lower tailings sample 

Stressed vegetation and surface water runoff through tailings 

Lower tailings sample location 

Lower tailings location and mill 

Cabin Creek downstream sample 

Cabin Creek view of mill 

Tailings visible.in creek slopes > 2 miles from lower tailings 

Confluence of Cabin Creek and Jack Creek 

Cabin Creek above confluence 
AR000056

URS 

Consultants, Inc. 

ARCS 

Photograph Log 

DCN # 

62760.35.20.1011 45 .a 

Project Number 

4 162760.35 

Project/Sice Name 

Nabesna Mine 

Photographer(s) 

Kara Steward 

Camera Type 

Canon 

Film Type/Speed 

Kodak 200 

Roll Number 

I 

Dace 

6/28/95 

Frame Date Time Orientation Subject 

I 6/20/95 1106 NE Mill building from south entrance 

2 6/20/95 I 106 E Ease wall of mill building 

3 6/20/95 

6/20/95 

6/20/95 

1107 s Tanks in building 

4 1111 NE Cyanide -tank in NW comer of mill building 

5 11 I I SE Ore grinder 

6 6/20/95 1115 N Zinc solution t.ank 

7 6120195 

6/20/95 

6/20/95 

6/20/95 

1115 E Tailings view from mill building 

8 1120 w Mine portal in hillside 

9 1130 NE I Panorama 1/4, Tailings 

10 1130 E Panorama 2/4, Tailings 

11 6/20/95 1130 SE Panorama 3/4, Tailings 

12 6/20/95 1130 E Panorama 4/4, Tailings 

13 6/20/95 1138 w Mill building and tailings from east 

14 6/20/95 1142 E Drums filled with tailings 

15 6/20/95 1146 SW Surface wacer drainage through tailings 

16 6/20/95 1205 w Former Nabesna post office 

17 6/20/95 1208 NW Nabesna town boardwalk 

18 6/20/95 13 13 w Cabin Creek upgradient of mill sample location 

19 6/20/95 1350 w Background mineralized sample location 

20 6/20/95 1450 SW North mill soil sample location 

21 6/20/95 1515 N South mill soil sample location, Assay office 

22 6/20/95 1550 w Tailings east of mill sample location 

23 6/20/95 1550 w Ea.st of mill sample location view of mill 

24 6/20/95 1700 w Southwest of mill building sample location 

25 6/20/95 1800 SE Field crew use of A TV for gear transport 
AR000064

APPENDIX B 

USGS MAP OF THE GEOLOGY OF THE AREA 

To receive a copy of Appendix B, please . 

submit a written request to USEPA Region 10. 

Your request should refer to the Nabesna Mine 

Site Investigati o n report. 

Upon receipt of a request, EPA will reproduce 

the 42"x26 " colored USGS map. 

The above is being suggested due to the-current 

resou rce/ funding situation. 
AR000066

APPENDIX C 

CROSS-SECTION MAP OF THE NABESNA MINE 
AR000071

APPENDIX D 

DIAGRAMS OF THE UPPER AND LOWER MINE TAILINGS 
} 

'-

Ii 

.-

I 

-r , • r 

_, 

.. ..:_: 

Nobesno 

Mill 

,,., 

-

.1e.3 ,. 7'11 .au

-.., 

.... 

~-a .42.4 

.Ja.a I ~ ,¥ 

•• 4' 

t

;-

I 

t 

NOTE.: 

,._, 

• 27..8 

... 

I 

I 

.---

.,., 

I 

i 

1 

! 

J 

I

; 

l 

I 

,_ 

! 

i 

} 

I 

I 

I 

' 

'

, 

- N CONl"OI.JRS ARE IN ·. NS AND ELEVATJO -LINE ST.(T!ON.. STATION =;~v..;; 1 

~EI..OW n-,E o•,o,ooH~1s:EWEEN ~900 ANO: -=-::-T A80 - ON OF 0-00 STA t - . - '"~ VATI ye,·· · 

TRUE ELE BOVE SEA-LE ........ : -. I . 3000 FEET ,\ . - - -

- - I 

' 

D IOO l'"llfT J SCALE• 

DATA BY•· 

-1-l.ll 

Rambler Mine Pro}~. -

NABESNA MILL T_AILINGS, 

TOPOGRAPHIC MAP 

OF UPPER TAILINGS 

' 

·~so· 

GC DA TE•10/l9BI FIG. 
AR000074

APPENDIX E 

CYANIDE PROCESS FLOW CHART 
AR000077

APPENDIX F 

WELL LOG 
AR000079

APPENDIX G 

NET PRECIPITATION 
AR000081

APPENDIXH 

DATA RESULTS AND VALIDATION 
AR000082

United States Department of the Interior 

NATIONAL PARK SERVICE 

Alaska Regional Office 

240 W. 5th Avenue, Room 114 IN REPLY REFER TO; Anchorage, Alaska 9950 I 

L3032(AKSO-RPR) CERTIFIED MAIL RETURN REQUESTED APR 28' 2004 

The Ptarmigan Co., Inc. 

C/O Mr. Kirk Stanley, President 

P.O. Box 200956 

Anchorage, Alaska 99502-0956 

Re: Nabesna Mine, Wrangell SI. Elias National Park and Preserve, Alaska 

eneral Notice Letter and Request for Information 

ursuant to Sections 104 and 107 of CERCLA 

G

P

Dear Mr. Stanley: 

This letter notifies you that The Ptarmigan Co., Inc. ('Ptarmigan") may be liable under 

Section 107(a) of the Comprehensive Environmental Response, Compensation, and 

Liability Act of 1980; 42 U.S.C.§ 9607(a), as amended ("CERCLA") in connection with the 

Nabesna Mine Site ("Site") near Nabesna, Alaska. This letter also notifies you of past 

and future response activities at the Site which Ptarmigan may be asked to facilitate, 

finance or otherwise participate in. Additionally, this letter requests that you provide 

certain information regarding the ownership and operation of the Site and the relationship 

of Ptarmigan to the Site. Ourrecords show that Ptarmigan has held an ownership 

interest in the Site since 1968. 

HISTORY OF SITE 

The Site is located in Wrangell-SI. Elias National Park and Preserve, Alaska, in Section 

21, Township 7 North, Range 13 East, Copper River Meridian. The Site is accessible by 

way of the 58 mile long Nabesna Road, a state right of way, beginning at Slana, and 

ending at the mine. The road is state maintained from Slana to a location approximately 

two miles north of the Site. 

The Site consists ofthe Sunshine patented lode mining claim and lapsed unpatented 

-mining claims located downslope of the Sunshine claim and now managed by the 

National Park Service ("Park Service") as part of Wrangell-SI. Elias National Park and 

Preserve. All of the claims which gave rise to the Site, including the Sunshine claim, 

were originally staked between 1903 and 1905. The Sunshine claim was patented in 

1932. 

Nabesna Mining Corporation performed hard rock gold mining at the Site from 1929 to 

1946. The mill used by Nabesna Mining Corporation for its mining operations is located 

on the Site, along with various other buildings used to support past mining operations. 

The Site is located near tree line on the talus slopes of White Mountain at an elevation of 
AR000083

3,100 feet. Tailings from the gold mining operations were deposited on the Site and 

cover approximately nine acres. We estimate that roughly 25 percent of the tailings are 

located on the Sunshine claim, and approximately 75 percent are downslope on lands 

currently managed by the Park Service. 

NOTICE OF POTENTIAL LIABILITY 

The United States Environmental Protection Agency ("USEPA"), the United States 

Geological Survey ("USGS") and the Park Service have conducted various investigations 

of the Site and have documented the release of hazardous substances as defined under 

CERCLA into the environment. Specifically, these investigations document that metals 

from the tailings have been released into soils and surface water which present exposure 

hazards to visitors to the Site and the em';ronmenl. As a result, the Site was placed on 

USEPA's CERCLA sites database. The State of Alaska also added the Site to its 

contaminated sites database, Vvhich is maintained by the Contaminated Sites Division of 

the Alaska Department of Environmental Conservation. Additionally, the State of Alaska 

added Cabin Creek to its Clean Water Act list of impaired water bodies. 

Pursuant to the authority granted to it under Executive Order 12580 to respond to 

releases of CERCLA hazardous substances, the Park Service has undertaken actions to 

investigate and control releases and threatened future releases of hazardous substances 

at the Site and is considering expending additional funds towards that end. The Park 

Service explored various options for remediation of the Site and has selected a preferred 

altemative involving diversion of surface waters from the tailings and possible capping of 

the tailings with a local talus source. Under Section 106(a) and 107(a) of CERCLA, 

potentially responsible parties ("PRPs") may be ordered to perform response actions 

necessary to protect the public health, welfare, or the environment and may be held liable 

for all costs incurred by the Park Service in responding to any release or threatened 

release at the Site. 

PRPs under CERCLA include current owners at the Site, past O'M'lers at the time 

hazardous substances were disposed of at the Site, persons who arranged for the 

disposal of hazardous substances at the Site and transporters of hazardous substances 

to the Site. Based on inbrmation reviewed by the Park Service to date, the Park Service 

believes that Ptarmigan, as a current owner and operator of the Site, may be a PRP at 

the Site. By this letter, the Park Service notifies you of your potential liability with regard 

to this matter and encourages your continued cooperation with the Park Service with 

respect to planned response activities at the Site. 

REQUEST FOR INFORMATION 

The Park Service appreciates that Ptarmigan has expressed interest in participating in 

implementation of the preferred remediation altemative for the Site and looks brward to 

working with Ptarmigan in that regard. Nevertheless, in responding to the documented 

release of hazardous substances at the Site, the Park Service is required to follow a 

prescribed regulatory process of inquiring into various matters. These matters include 

identifying the nature and quantity of hazardous substances that have been released at 

the Site and the connection between PRPs and the release of hazardous substances at 

the Site. Additionally, the Park Service must also seek information relating to the ability 

of PRPs to pay for or perform a cleanup of the Site. As a result, pursuant to the authority 
AR000084

of Section 104 ofCERCLA, 42 U.S.C. § 9604, as amended, the Park Service hereby 

requests that Ptarmigan respond to the information request set forth in Enclosure 1, 

attached hereto. 

Your response to this Information Request should be sent 

C/O Linda Stromquist 

CERCLA Program Manager 

National Park Service 

240 W. 5th Avenue #114 

Anchorage, Alaska 99501-2327 

The Park Service strongly encourages Ptarmigan to give this matter its immediate 

attention and to respond to this Information Request within 60 days. Under CERCLA, 

failure to respond to this request with 60 days or to adequately justify any failure to 

respond could result in the commencement of judicial or administrative action to compel 

compliance with the information request or the imposition of civil penalties not to exceed 

$32,500 per day of noncompliance (see 42 U.S.C. §§ 104(e)(5)(A) & (8». 

If you have any questions regarding this Information Request, or Ptarmigan's role in 

response activities planned for the Site, please contact Linda Stromquist at (907) 644-

3576 or, in her absence, Danny Rosenkrans at (907) 822-7240. Alternatively, 

Ptarmigan's attorney may contact Lisa Toussaint of the Regional Solicitor's Office for the 

Department of the Interior at (907) 271-4131 regarding this matter. 

Sincerely, 

Marcia 81asza 

Regional Dir tor 

Enclosures 2 

1-lnformation Request (5 pp) 

2-Notarized Certificate (1 p) 

cc: 

Lisa Toussaint, DOl-SOL 

Linda Stromquist, NPS-AKSO 

Gary Candelaria, NPS-WRST 

Danny Rosenkrans, NPS-WRST 
AR000085

Nabesna Mine Site - Enclosure 

INFORMATION REQUEST 

Definitions 

The following definitions shall apply to the following words as they appear in this 

Enclosure: 

1. The term "Ptarmigan" shall mean The Ptarmigan Co., Inc. its officers, 

managers, employees, contractors, trustees, partners, successors, 

assigns, and agents. 

2. The term "person" shall have the same definition as in Section 101(21) of 

CERCLA: an individual, firm, corporation, association, partnership, 

consortium, joint venture, commercial entity, United States Government, 

State, municipality, commission, political subdivision of a State, or any 

interstate body. 

3. The term "the Site" shall mean the Nabesna Mine site. 

4. The term "hazardous substance" shall have the same definition as that 

contained in Section 101(14) of CERCLA and includes any mixtures of 

such hazardous substances with any other substances, including 

petroleum products. 

5. The term "release" has the same definition as that contained in Section 

101 (22) of CERCLA, 42 U.S.C. § 9601 (22), and includes any spilling, 

leaking, pumping, pouring, emitting, empt',ing, discharging, injecting, 

escaping, leaching, dumping, or disposing into the environment, including 

the abandonment or discharging of barrels, containers, and other closed 

receptacles containing any hazardous substance. 

6. The terms "document" and "documents" shall mean anywrillng, recording, 

or stored information and includes, but is not limited to, witings of any 

kind, formal or informal, whether or not wholly or partially in handwriting, 

including by way of illustration and not by way of limitation, any invoice, 

manifest, check, deposit slip, 1I.ithdrawal slip, order, correspondence, 

record book, minutes, memorandum of telephone and other 

conversations, including meetings, agreements, and the like, diary, 

calendar, desk pad, scrapbook, notebook, bulletin, circular, form, 

pamphlet, statement, joumal, postcard, letter, telegram, telex, report, 

notice, message, analysis, comparison, graph, chart, interoffice or intra 

office communications, photostat or photograph, sound recording or any 

type of device, any punch card, disc or disc pack: any tape or other type of 

memory generally associated with computers and data processing 

(together with the programming instructions and other written malerial 

necessary to use such punch card, disc, or disc pack, tape or other type 

of memory and together with printouts of such punch card, disc, or disc 

pack, tape or other type of memory); and (a) every copy of each document 

which is not an exact duplicate of a document which is produced, 
AR000086

(b) every copy which has writing, figure or notation, annotation or the like 

on it, (c) drafts, (d) attachments to or enclosures with any document, and 

(e) every document referred to in any other document. 

7. The term "property interest" means any interest in property including, but 

not limited to, any ownership interest, including an easement or right of 

way, any interest in the rental of property, any interest as either the trustee 

or beneficiary of trust that owns or rents, or owned or rented property. 

8. The term "mining operations" shall mean mining, milling, smelting, 

exploration, sampling, drilling, or moving materials, as well as developing 

or improving any road or trail to facilitate access to the site for the purpose 

of any of the foregoing activities. 

Questions 

Insurance Information 

1. Please identify all liability insurance policies held by Ptarmigan that cover or may 

cover activities associated with the Site or Ptarmigan's potential liability at the 

Site. For each such policy, please state: 

a. the name and address of the insurer and the insured; 

b. the amount of coverage under the policy; 

c. the dates of the commencement and expiration of the policy; 

d. whether the policy contains a "pollution exclusion" clause; and 

e. whether the policy covers or excludes sudden, non-sudden or both types 

of accidents. 

2. Please provide .copies of all policies identified in response to Question 1. 

Corporate and Financial Information 

3. Please identify all of Ptarmigan's current assets and liabilities. 

4. Please provide copies of all financial statements and financial reports filed by 

Ptarmigan with any governmental entity (e.g., the Securities and Exchange 

Commission) or any financial institution (e.g., bank) for the last five (5) years. 

5. Please identifY any other person or entity that may be responsible for the liabilities 

of Ptarmigan arising from or related to the release or threatened release of 

hazardous substances at the Site. 

6. Please identifY all parent corporations of Ptarmigan. 

7. Please identifY all subsidiaries of Ptarmigan. 
AR000087

8. Please identio/ all of the shareholders of Ptarmigan and their respective 

percentage of ownership of shares in Ptarmigan. 

9. Please provide copies of'all financial statements or financial reports filed by each 

of the shareholders of Ptarmigan with any governmental entity (e.g., the 

Securities and Exchange Commission) or any financial institution (e.g., bank) for 

the past five (5) years. 

Ptarmigan's ProperlY Interest in the Site 

10. Our records identify Ptarmigan as one of the current owners of the Site. With 

regard to Ptarmigan's property interest at the Site, please identio/: 

a. The date when Ptarmigan acquired its property interest in the Site; and 

b. The party or parties from whom Ptarmigan acquired its property interest in 

the Site. 

11. Did Ptarmigan ever transfer any portion of its property interest at the Site to 

another party? If the answer to this question is 'Yes," with regard to each such 

property interest transferred, please identify: 

a. the name of the parties to whom Ptarmigan transferred such a property 

interest; 

b. the nature of the property interest transferred; and 

c. the date on which the transfer of the property interest occurred. 

Mining Operations at the Site 

12. Has Ptarmigan or any of its agents, assignees, leasees or contractors ever 

performed any mining operations, as defined in the Definitions section herein, at 

the Site? If the answer to this question is 'Yes," please identify for each such 

mining operation: 

a. the nature of the mining operation; 

b. the date or dates on which the mining operation occurred; and 

c. the specific location at the Site of the mining operation. 

13. Does Ptarmigan have any knowledge that Sierra Industries, Inc. performed any 

mining operations at the Site? If the answer to this question is 'Yes," please 

identify for each such mining operation: 

a. the nature of the mining operation; 

b. the date or dates on which the mining operations occurred; and 
AR000088

16 

c. the specific location at the Site of the mining operations. 

14. .• Does Ptarmigan have any knowledge that Nabesna, Inc. performed any mining 

operations at the Site? If the answer to this question is ''Yes,'' please identify for 

.- each such mining operation: 

,a. the nature of the mining operation; 

b. the entity which performed the mining operation; 

c. the date or dates on which the mining operation occurred; 

d. the specific location at the Site of the mining operation. 

Corporate Historv of Other Entities 

15. Does Ptarmigan have any knowledge of any acquisition, asset or stock sale, 

merger or consolidation involving any two or more of the following business 

entities: 

a. Nabesna Mining Corporation; 

b. Nabesna Mining Company, Inc.; 

c. Sierra Industries, Inc.; or 

d. Nabesna, Inc. 

e. Ptarmigan 

If the answer to Question 15 is ''Yes,'' please identify for each such acquisition, 

sale, merger or consolidation: 

a. the name of the party or parties engaged in such transaction; 

b. the date when such transaction occurred; and 

c. the nature of such transaction. 

17. Please provide copies of any documents related to each such transaction 

identified in response to Question 16. 

18. Does Ptarmigan have any knowledge of whether Nabesna Mining Corporation or 

Nabesna Mining Company, Inc. was involved in a merger, asset or stock sale, or 

consolidation with any other entity not identified in Question 15? If the answer to 

this question is ''Yes,'' please identify with regard to each such merger, sale or 

consolidation: 

a. the name of the party or parties with whom Nabesna Mining Corporation 

or Nabesna Mining Company, Inc. engaged in such a transaction; 
AR000089

b. the date when such transaction occurred; 

c. the nature of such transaction. 

19. Please provide copies of any documents related to each such transaction 

identified in response to Question 18. 

20. Does Ptarmigan have any knowledge of whether Nabesna Mining Corporation or 

Nabesna Mining Company, Inc. liquidated its assets, \M3nt into bankruptcy or 

otherwise dissolved!? If the answer to this question is 'Yes," please identify: 

a. the nature of such liquidation, bankruptcy or dissolved; and 

b. the date when such liquidation, bankruptcy or dissolved occurred. 

21. Please provide copies of any documents related to each such transaction 

identified in response to Question 20. 

22. If you have reason to believe that there may be persons able to provide a more 

detailed or complete response to any of the questions contained herein or who 

may be able to provide additional responsive documents, please identify those 

persons and the additional information or documents that you believe they may 

have. 
AR000090

NOTARIZED CERTIFICATE 

FOR THE NABESNA MINE SITE 

1._;---:--:-________, having been duly swom and being of legal age, 

hereby state: 

I am the person authorized by Ptarmigan, Inc. to respond to the National Park 

Service information request conceming the Nabesna Mine Site located in WrangellSt. Elias National Park and Preserve, Alaska. 

2. I have made a complete and thorough review of all documents, information, and 

sources relevant to the request. 

3. I hereby certify that the attached response to the Park Service's request is complete 

and contains all in1brmation and documents responsive to the request. 

(Signature and Title) 


States Department of the Interior 

NATIONAL PARK SERVICE 

Alaska Regional Office 

240 W. 5th Avenue, Room 114 IN REPLY REFER TO: Anchorage, Alaska 99501 

(AKRO-RNR) CERTIFIED MAIL 

N3035 RETURN RECEIPT REQUESTED 

JUN 2 2 2005 

Ptarmigan Company, Inc. 

c/o Mr. Kirk Stanley, President 

P.O. Box 200956 

Anchorage, Alaska 99502-0956 

RE: Nabesna Mine, Wrangell-St. Elias National Park and Preserve, Alaska. 

Supplemental Request for Information - Section 104 of CERCLA 

Dear Mr. Stanley: 

This letter supplements the information requests set forth in our April 28,2004, 

letter to Ptarmigan Company, Inc. ("Ptarmigan") pursuant t .o Section 104 (e) of 

CERCLA, 42 U.S.C.§9604(e), as amended, in connection with the Nabesna Mine Site 

located in Wrangell-St. Elias National Park and Preserve in Alaska. 

Please respond to the information requested in the enclosure attached to this 

letter. We ask that you provide the information within thirty(30)days of 

receiving it and that your response is sent to: 

C/0 Linda Stromquist 

CERCLA Program Manager 

National Park Service 

240 West 5th Avenue #114 

Anchorage, Alaska 99501-2327 

If you have any questions regarding this request, please contact Linda 

Stromquist at (907)644-3576 or, in her absence., Danny Rosenkrans at 

(907)822-7240. Alternatively, Ptarmigan's attorney may contact Lisa Toussaint 

of the Regional Solicitor's Office for the Department of the Interior at (907) 

271 - 4131. 

Sincerely, 

t. Marcia ~ Blaszak 

Regional Dir~ctor 

Enclosures (3) 

1-Information Request(2pp) 

2-Notarized Certificate(lp) 

3-Exhibit A (2pp) 

cc 

Lisa Toussaint,DOI-SOL 

2005_06_22_104E_Supplement_Stanley

2005_06_22_104E_Supplement_Stanley
Nabesna Mine Site - Enclosure 1 INFORMATION REQUEST Definitions The following definition shall apply to the 

following words as they appear in this 

Enclosure: 

The Term "Ptarmigan" shall mean The Ptarmigan Company, Inc., its officers, manager, employees, contractors, 

trustees, partners, successors, assigns, and agents. 

Questions 

1. Provide copies of all income tax returns filed by Ptarmigan with the federal Internal Revenue Service for the past five ( 

5) years. 

2. Identify the total amount of gross income Ptarmigan has received in each of the following calendar years: 2001, 2002, 

2003, 2004, and 2005. 

3. Identify all assets of Ptarmigan that have been distributed to any shareholder of Ptarmigan at any time since January 1, 

2001 to the present. 

4. Identify the salaries which have been paid to the President of Ptarmigan during each of the following calendar years: 

2001, 2002, 2003, 2004 and 2005. 

5. Identify the salaries which have been paid to the-Vice-President of Ptarmigan during each of the following calendar 

years: 2001, 2002, 2003, 2004, and 2005. 

6. Identify the salaries which have been paid to the Treasurer ofPtarmigan during each of the following calendar years: 

2001, 2002, 2003, 2004, and 2005. 

7. Identify the current balance in each checking account Ptarmigan has with a bank or other financial institution. 

8. Identify all assessments or appraisals ofthe Ptarmigan property (USMS 1591) made at any time after January 1, 2001, 

including but not limited to any assessed value of the property for property tax purposes and any appraisal prepared for 

the purpose of selling the property. 

9. Identify the date and amount of each financial contribution to capital made by each shareholder ofPtarmigan since 

January 1, 2001. 

10. Please provide a copy ofthe Biennial Report filed by Ptarmigan with the State of Alaska for the period ending 

December 31, 2004. 

11. The attached page marked as Exhibit A is from the corporate database available on the website for the State of Alaska 

Department of The page states that neither you (Kirk Stanley) nor any of the other officers ofPtarmigan owns any 

shares of Ptarmigan. However, in your response to the 104 (e) Information Commerce. 
AR000095

PTARMIGAN COMPANY, INC. 

'g)_ D. !Box 200956 

df-ncho'l.a_gE-, c/l-(a:1k.a 99502-0956 

August 2,2005 

Ms. Marcia Blaszak 

Regional Director, National Park Service 

240 W. 5th Avenue, Room 114 

Anchorage, Alaska 99501 

Re:Nabesna 

Dear Director Blaszak: 

Superintendent Jed Davis twice in July came to Nabesna. Few others ever 

bothered to do that. He got a good look at the place and the 70-year-old 

mill tailings. 

Several in NPS have for the past 11 years made a career out ofthose old 

tails, caused the government to spend hundreds ofthousands ofdollars and 

accomplished practically nothing. 

Superintendent Davis on his second time at Nabesna asked in a reasoned 

manner ifI would be willing to work with DEC regarding the mill tailings 

on private land. NPS would confine their interest to park managed lands. I 

agreed absolutely. He said he would'work out the details. 

Something ofvalue, I believe, will come out ofthis new arrangement. 

I wonder in view ofthe new arrangement ifthere is any useful reason for the 

very personal information sought by your June 22, 2005 letter, the letter I 

understand Ms. Stromquist drafted. 

Thank you 

Sincerely yours, 

~v.1μ., 

Kirk W. Stanley 

Cc: Superintendent Jed Davis 
Community Fact Sheet

Nabesna Mine Site

National Park Service

U.S. Department of the Interior

Wrangell-St. Elias National Park

and Preserve

A SITE HISTORY...

Wrangell-St. Elias National Park and Preserve (WRST) 

encompasses nearly 13.2 million acres of land in 

southeastern Alaska and is part of a World Heritage 

Area. The Nabesna Mine and mill buildings are located 

within WRST on land owned by the Ptarmigan 

Company at the end of the 46-mile long Nabesna Road. 

The Nabesna Mine and mill camp includes 

approximately 35 historic buildings that were utilized

throughout the 1930s. It is on the National Register of 

Historic Places. Gold mining and milling operations

were conducted between 1925 and 1940; past milling 

processes included grinding and flotation and the use of 

both mercury and cyanide at different times. Finely 

milled pyrite (iron and sulfur) tailings left over from the 

ore processing are located down slope from the buildings. 

AND NOW...

The mine, mill, and some of the associated mill tailings, are located on the Sunshine Lode mining claim, 

patented to the Nabesna Mining Corporation. The remaining tailings are situated on federal land managed 

by the National Park Service (NPS), on the north and south sides of Nabesna Road. The mill tailings cover 

approximately 9 acres, with an average thickness of approximately 1.5 feet. Currently, the mill and camp are 

in disrepair and the tram system used to transport ore from the mine adits is partially collapsed. The ironrich surface of the tailings has oxidized and appears as a bright orange and grey packed crust. In general, the 

tailings do not support vegetation, are acidic, and contain heavy metals such as lead, cadmium, nickel, and 

arsenic (a m

Trail

Trail

Nabesna Road

etalloid). 

AR000096
ENVIRONMENTAL INVESTIGATIONS...

Environmental investigations at the Site have been 

undertaken previously to define the area covered by 

tailings and to determine the risks the tailings may 

pose to human health and the environment. Samples 

indicate that there are concentrations of metals in the 

tailings which are above regulatory standards. These 

metals may have washed and leached into Cabin Creek 

during periods of high water flow, such as spring 

runoff. Compounds of potential concern in the tailings 

and surface soils include arsenic, cadmium, chromium, 

mercury, nickel, and lead. Sediments in Cabin Creek 

contain elevated levels of silver, arsenic, cadmium, and 

lead. Metals also have been found to be mobilized to Cabin Creek with surface water runoff during the 

wet season, with some metals remaining in surface water through the dry season. Subsequent to these 

investigations, the NPS constructed ditches along the southern side of the tailings that redirect surface 

water flow away from the tailings. 

The NPS has initiated an Engineering Evaluation/Cost Analysis (EE/CA) to determine the full nature and 

extent of contamination at the Site pursuant to the Comprehensive Environmental Response, 

Compensation, and Liability Act (CERCLA). As part of the EE/CA, previously collected data and new 

data collected in the 2009 field season will be used to conduct ecological and human health risk 

assessments to identify potential risks posed by Site contaminants. The EE/CA also will evaluate the 

need for cleanup action and the effectiveness, 

feasibility, and cost of a range of cleanup alternatives. 

Additional information necessary for removal action 

design will be identified in the EE/CA Report, which 

will include an outline of design information needs. A 

cleanup action, if deemed necessary, will be selected as 

part of the EE/CA process. 

COMMUNITY INVOLVEMENT... 

The public and local community will have the 

opportunity to review and comment on the Nabesna 

EE/CA Report, including the preferred cleanup alternative. The EE/CA Report is expected to be available 

for public review by spring 2010. The administrative record file, which contains all of the documents 

upon which the selection of cleanup action will be based, has been established and is available for public 

review at the following two locations: 

National Park Service National Park Service

Alaska Regional Office 1050 Walnut Street, Suite 220 

240 West 5th Avenue Boulder, Colorado 80302 

Anchorage, Alaska 99501 Contact: Gregory Nottingham 

Contact: Linda Stromquist Phone: (303) 415-1483 

Phone: (907) 644-3576 Mon.-Fri. 9:00 a.m. – 4:00 p.m. 

Mon.-Fri. 9:00 a.m. – 5:00 p.m. 

FOR MORE INFORMATION...

If you have questions concerning the Nabesna Mine EE/CA, please contact Greg Nottingham at (303) 

415-1483 or Danny Rosenkrans at Park Headquarters in Copper Center (907) 822-7240. 

May 2009

AR000097
AR000099

United States Department of the Interior 

NATIONAL PARK SERVICE 

Wrangell..St. Elias National Park & Preserve 

Mile 106.8 Richardson Hwy. P.O. Box 439 

Copper Center, AK 99573-0439 

907 822 5234 Fax 907 822 7216 

L3023 (WRST-AD) 

June 10, 2009 

Mr. Kirk Stanley 

Ptarmigan Company 

P.O. Box 200956 

Anchorage,AK 99502-0956 

Dear Mr. Stanley: 

As you know, the National Park Service (NPS) is in the process of evaluating potential cleanup actions 

for the Nabesna Mine Site (Site). Additional data is needed to fully characterize the Site and NPS would 

like to collect that data this field season. This correspondence is intended to let you know about the 

upcoming activities at the Site and to solicit your continued cooperation in this effort. 

Our contractor, The Johnson Company, plans to arrive at the Site on or around August 7 to meet with my 

staff, Danny Rosenkrans, and receive Site orientation and safety information. Site investigation activities 

are expected to take place between August 11 and September 6, 2009. These activities will inciude the 

installation ofseveral ground water wells, as well as soil, tailings, sediment, and surface water sampling. 

In preparation for this field work, our drilling subcontractor, Denali Drilling, will visit the Site with 

Danny on June 12 to evaluate Site conditions and plan for the August field work. 

For your reference, enclosed are two Community Fact Sheets that provide additional information on Site 

activities. We greatly appreciate your willingness to provide NPS and its contractor's access to your 

property as we take this important step toward resolution of contaminant concerns at the Site. If you have 

any questions or concerns, please contact me at 907-822-7202 or Danny Rosenkrans at 907-822-7240. 

Sincerely, 

Meg Jensen 

Superintendent 

Enclosures 

Cc: G. Nottingham 

L. Stromquist 

Nabesna District Ranger 
2009 Field Investigation 

Community Fact Sheet

Nabesna Mine Site

National Park Service

U.S. Department of the Interior

Wrangell-St. Elias National Park 

and Preserve

This fact sheet is a supplement to the May 2009 Community Fact Sheet for the Nabesna

Mine Site, describing Site conditions and the Engineering Evaluation/Cost Analysis (EE/CA) 

process underway at the Site.

SUMMER 2009

During the month of August 2009, the National Park 

Service (NPS) will be completing an environmental 

investigation of the Nabesna Mine Site (Site) at the end of 

the Nabesna Road in Wrangell-St. Elias National Park and 

Preserve (WRST). The field work will be led by NPS 

contractor, The Johnson Company, who will be performing 

environmental drilling and sampling from approximately 

August 10 to September 6, 2009. Although most of the 

work will focus on the tailings piles located on either side 

of Nabesna Road, NPS also will be accessing creeks and 

streams to the north and south of the tailings. The 

investigation will include drilling soil borings and installing 

groundwater monitoring wells on and near the tailings, 

collecting groundwater samples, sampling surface water 

and sediment from Cabin Creek and Jack Creek, and collecting soil samples. This investigation is needed to fill 

data gaps and update Site information to permit the full characterization of the Site consistent with applicable 

laws and regulations. The data will be used to identify Site contaminants, determine pathways of contaminant 

migration, evaluate human and ecological risk, and analyze an array of potential cleanup alternatives. The 

resulting information will be presented for public review and comment in an EE/CA Report expected to be 

completed by spring 2010. This will be a significant milestone in the process of addressing human health and 

environmental concerns at the Site. 

The investigation will involve the use of two track-mounted drill rigs. These rigs are expected to make one trip 

each way along Nabesna Road and spend the remaining time at the Site. Trucks and all-terrain vehicles also 

will be used to transport equipment and workers to and from the Site each day. 

The Nabesna area of WRST and Nabesna Road will not be closed to traffic or visitors during this investigation. 

Residents and visitors, however, are asked to take extra precautions for their safety and the safety of the 

sampling crew. Please drive carefully between Devil’s Mountain Lodge and the Nabesna Mine Site since the 

crew will use this road often. It is recommended that a safety zone of 25 feet be maintained around any

working drill rig. Drums should not be opened or otherwise disturbed at the Site because they could contain 

contaminated material from the drilling and sampling activities. If you are hunting in the area, be aware that a 

sampling crew may be moving within a mile radius of the Site through brush or trees by foot or on off-road 

vehicles. If you see or know of any dangerous conditions or potentially threatening animal activity, please 

advise a member of the sampling team or a WRST Ranger immediately.

FOR MORE INFORMATION

If you have questions concerning the field work or any aspect of the Nabesna Mine Site EE/CA, please contact 

Greg Nottingham at (303) 415-1483 or Danny Rosenkrans at Park Headquarters in Copper Center (907) 822-

7240. 

June 2009

AR000098
AR000100

United States Department of the Interior 

NATIONAL PARK SERVICE 

Wrangell-St. Elias National Park/Preserve 

Mile 106.8 Richardson Hwy. P.O. Box 439 

Copper Center, AK 99573-0439 

907 822 5234 Fax 907 822 7216 

L3023 (T10-114_Lands)

July 1, 2009

Dear Alaskan:

The National Park Service (NPS) at Wrangell-St. Elias National Park and Preserve is 

undertaking studies in the Nabesna Mine area to document and assess current 

environmental conditions associated with past mining. Our records indicate that you 

proposed live, recreate, activities engage which in subsistence, are planned fhunt orhis or pocming tentially summer. wouldhave Copies an of interest two fact in our

sheets pertaining to the Nabesna Mine are enclosed. We anticipate that there will 

additional at the Nabesna mailings Minie nafter the future. reading Ifthe you fact have sheets, any questions please contact regarding me the or LNPS and Manager, activities 

Danny Rosenkrans at 907-822-5234.

Sincerely

Supenntendent 

Meg Jensen

Enclosures

Cc: AKRO_ Stromquist
Nabesna Mine Site

Community Fact Sheet

February 2010 Update

National Park Service

U.S. Department of the Interior

Wrangell-St. Elias National Park 

and Preserve

This fact sheet is an update of recent activities related to the Engineering Evaluation/Cost 

Analysis (EE/CA) process underway at the Nabesna Mine Site.

SUPPLEMENTAL SITE 

INVESTIGATION 

In August 2009, the National Park Service 

(NPS) undertook environmental sampling of the 

Nabesna Mine Site (Site), located at the end of 

the Nabesna Road in Wrangell-St. Elias 

National Park and Preserve (WRST). This 

Supplemental Site Investigation (SSI) was 

conducted to address data gaps and update 

existing Site information for characterization of 

the Site, to facilitate the evaluation of human 

and ecological risks at the Site, and to support 

the development and evaluation of Site cleanup 

alternatives. 

The following activities were conducted as components of the 2009 SSI. Additional groundwater data were 

acquired to fully assess environmental contamination and transport mechanisms. These data were collected 

through the installation and sampling of eight monitoring wells. In the process of drilling the monitoring wells, 

soil borings were taken. These boreholes provided information regarding the relationship between subsurface 

geology and permafrost on groundwater and surface water. The SSI included sampling of surface water and 

sediment at 23 locations. The Site is located in an area with naturally occurring metal-rich soils. Hence it

required a thorough examination of the background characteristics of soil, sediment, and surface water in order 

to establish Site-specific background concentrations for consideration in the selection of Site cleanup goals. A 

delineation of the tailings was completed through visual observations and field screening of metals in surface 

soils at approximately 230 locations. 

This information will be used in the assessment of site conditions, risk to human health and ecological 

receptors, regulatory compliance, and cleanup alternatives. The results will be incorporated into an EE/CA 

Report that will be made available to the public upon completion (anticipated to be fall 2010 or later). 

FOR MORE INFORMATION

If you have questions concerning the field work or any aspect of the Nabesna Mine Site EE/CA, please contact 

Greg Nottingham at (303) 415-1483 or Danny Rosenkrans at Park Headquarters in Copper Center (907) 822-

7240. 

AR000486
Document: AR000001 AR000081 Date: 1995 09 26

Title:

Document Type:

Authors: URS Consultants, Inc

Author Affiliation: EPA Region 10 Contractor

Document: AR000082 AR000090 Date: 2004 04 28

Title:

Document Type:

Authors: Marcia Blaszak

Author Affiliation: Regional Director, National Park Service Alaska Regional Office

Addressees:

Addressee Affiliation: Landowner, private portion of Nabesna site

Document: AR000091 AR000092 Date: 2004 06 07

Title:

Document Type:

Authors:

Author Affiliation: Landowner, private portion of Nabesna site

Addressees:

Addressee Affiliation: National Park Service Alaska Regional Office

Document: AR000093 AR000094 Date: 2005 06 22

Title:

Document Type:

 Authors: Marcia Blaszak

Author Affiliation: Regional Director, National Park Service Alaska Regional Office

Addressees:

Addressee Affiliation: Landowner, private portion of Nabesna site

Linda Stromquist

INDEX FOR ADMINISTRATIVE RECORD

Nabesna Mine Site

March 2021

Site Inspection Report for the Nabesna Mine, Nabesna, Alaska, CERCLIS ID No. 

AK0000333021

Report

Ptarmigan Co. Notice Letter and Information Request 2004 04 28

104(e) information request

Kirk W. Stanley

Letter to Linda Stromquist from Kirk Stanley: Response to CERCLA 104(e) 

information request 04/28/2004

Letter

Kirk W. Stanley

Supplemental Request for Information to Mr. Stanley 2005 06 22

104(e) information request

Kirk W. Stanley
Document: AR000095 AR000095 Date: 2005 08 02

Title:

Document Type:

Authors:

Author Affiliation: Landowner, private portion of Nabesna site

Addressees: Marcia Blaszak

Addressee Affiliation: Regional Director, National Park Service Alaska Regional Office

Document: AR000096 AR000097 Date: 2009 05

Title:

Document Type:

 Authors: Wrangell-St. Elias National Park & Preserve

Author Affiliation: Wrangell-St. Elias National Park & Preserve

Document: AR000098 AR000098 Date: 2009 06

Title:

Document Type:

Authors: Wrangell-St. Elias National Park & Preserve

Document: AR000099 AR000099 Date: 2009 06 10

Title:

Document Type:

Authors:

Author Affiliation: Superintendent, Wrangell-St. Elias National Park and Preserve

Addressees:

Addressee Affiliation: Landowner, private portion of Nabesna site

Document: AR000100 AR000100 Date: 2009 07 01

Title:

Document Type:

Authors:

Author Affiliation: Superintendent, Wrangell-St. Elias National Park and Preserve

Addressees: Nabesna mine interested parties mailing list

Document: AR000101 AR000485 Date: 2009 08

Title:

Document Type:

 Authors: The Johnson Company

Author Affiliation: National Park Service Contractor

Document: AR000486 AR000486 Date: 2010 02

Title:

Document Type:

Authors: Wrangell-St. Elias National Park and Preserve

Community Fact Sheet

Letter to Marcia Blaszak from Kirk Stanley: Response to supplemental information 

request

Letter

Kirk W. Stanley

Community Fact Sheet: Nabesna Mine Site

Supplemental Site Investigation

2009 Field Investigation Community Fact Sheet, Nabesna Mine Site

Community Fact Sheet

Letter to Kirk Stanley from Meg Jensen 2009 06 10

Letter

Meg Jensen

Kirk W. Stanley

Cover Letter for May and June 2009 Nabesna Community Fact Sheets

Cover Letter

Meg Jensen

Nabesna Mine Supplemental Site Investigation Report

Nabesna Mine Site Community Fact Sheet: February 2010 Update

Community Fact Sheet
Document: AR000487 AR000488 Date: 2021 05

Title:

Document Type:

Authors: Wrangell-St. Elias National Park & Preserve

Document: AR000489 AR000526 Date: 2021 05 

Title:

Document Type:

Authors: National Park Service Environmental Compliance and Cleanup Division

Community Update: Nabesna Mine Site Administrative Record File Update

Community Fact Sheet

Community Involvement Plan: Nabesna Mine Site, Wrangell-St. Elias National Park 

and Preserve, Alaska

Community Involvement Plan
NABESNA MINE

AUGUST 2009 SUPPLEMENTAL SITE INVESTIGATION REPORT

AR000102

Title: Nabesna Mine Supplemental Site Investigation Report

Site Name: Nabesna Mine Site

Site Location: WRST, Alaska

TABLE OF CONTENTS

1. INTRODUCTION ........................................................................................................... 1

2. SITE BACKGROUND.................................................................................................... 1

2.1 General Sampling Objectives ........................................................................................... 1

2.2 Geology ............................................................................................................................ 3

3. BACKGROUND SOIL SAMPLING .............................................................................. 5

3.1 Purpose and General Approach: Background Soil Sampling.......................................... 5

3.2 Locations: Background Soil Samples.............................................................................. 6

3.3 Methods: Background Soil Sampling.............................................................................. 8

3.4 Results: Background Soil Sampling................................................................................ 8

4. DELINEATION OF TAILINGS IMPACTS................................................................. 11

4.1 Purpose and General Approach: Delineation of Tailings Impacts ................................ 11

4.1.1 Purpose and General Approach: Areal Extent of Tailings Impacts..................... 11

4.1.2 Purpose and General Approach: Vertical Extent of Tailings Impacts................. 12

4.2 Sampling locations: Delineation of Tailings Impacts ................................................... 12

4.2.1 Sample Locations: Areal Extent of Tailings Impacts .......................................... 12

4.2.2 Sample Locations: Vertical Extent of Tailings Impacts ...................................... 13

4.3 Methods: XRF Screening .............................................................................................. 13

4.3.1 Methods: Areal Extent of Tailings Impacts ......................................................... 15

4.3.2 Methods: Vertical Extent of Tailings Impacts ..................................................... 15

4.4 Results: Delineation of Tailings Impacts ...................................................................... 16

4.4.1 Results: Areal Extent of Tailings Impacts ........................................................... 16

4.4.2 Results: Vertical Extent of Tailings Impacts ....................................................... 18
5. GROUNDWATER INVESTIGATION ........................................................................ 19

5.1 Purpose and General Approach: Groundwater Investigation........................................ 19

5.1.1 Purpose and General Approach: Monitoring Wells............................................. 19

5.2 Locations: Groundwater Investigation ........................................................................... 20

5.2.1 Locations: Monitoring Wells ............................................................................... 20

5.3 Sampling and Analytical Procedures: Groundwater Investigation................................ 21

5.3.1 Sampling and Analytical Procedures: Well Installation ...................................... 21

5.3.2 Sampling and Analytical Procedures: Water Level Monitoring .......................... 22

5.3.3 Sampling and Analytical Procedures: Monitoring Well Sampling...................... 22

5.4 Results: Groundwater Investigation .............................................................................. 24

5.4.1 Results: Hydraulic Gradients and Groundwater Flow Direction......................... 24

5.4.2 Results: Groundwater Analysis............................................................................ 25

6. SURFACE WATER AND SEDIMENT ASSESSMENT............................................. 25

6.1 Purpose and General Approach: Surface Water and Sediment Assessment ................. 25

6.2 Locations: Surface Water and Sediment Assessment ................................................... 25

6.3 Methods: Surface Water and Sediment Assessment ..................................................... 28

6.3.1 Methods: Surface Water Mapping ........................................................................ 28

6.3.2 Sampling and Analytical Procedures: Surface Water Sampling.......................... 28

6.3.3 Sampling and Analytical Procedures: Sediment Sampling ................................. 29

6.4 Results: Surface Water and Sediment Assessment ....................................................... 29

6.4.1 Results: Stream Channel Mapping........................................................................ 29

6.4.2 Results: Surface Water and Seep Sampling ......................................................... 31

6.4.3 Results: Sediment Sampling ................................................................................ 32

7. ANALYSIS: NATURE AND EXTENT OF CONTAMINATION ............................. 34

7.1 Analysis: Background Soil Concentrations................................................................... 34

7.2 Analysis: Background Surface Water Concentrations .................................................. 35

7.3 Analysis: Background Sediment Concentrations .......................................................... 35

7.4 Analysis: Extent of Tailings and Impacted Soil ............................................................ 35

7.5 Analysis: Impacts to Groundwater ................................................................................ 37
7.6 Analysis: Impacts to Surface Water and Sediment ....................................................... 37

8. CHARACTERIZATION TO SUPPORT POTENTIAL RESPONSE ACTIONS........ 38

8.1 Geotechnical Sampling................................................................................................... 38

8.1.1 Purpose and General Approach: Geotechnical Sampling.................................... 38

8.1.2 Locations: Geotechnical Samples ........................................................................ 38

8.1.3 Methods: Geotechnical Soil Borings ................................................................... 38

8.1.4 Sampling and Analytical Procedures: Geotechnical Soil Sampling.................... 39

8.1.5 Sampling and Analytical Procedures: Tailings Samples for Geotechnical

Analysis......................................................................................................... 39

8.1.6 Results: Geotechnical Sampling .......................................................................... 40

8.2 Tailings Reprocessing Samples...................................................................................... 40

8.2.1 Purpose and General Approach: Tailings Reprocessing Samples ....................... 40

8.2.2 Locations: Tailings Reprocessing Samples ......................................................... 40

8.2.3 Sampling and Analytical Procedures: Tailings Reprocessing Samples............... 40

8.2.4 Results: Tailings Reprocessing Samples ............................................................. 41

9. FIELD OPERATIONS .................................................................................................. 41

9.1 Site Reconnaissance, Preparation, and Restoration Procedures ..................................... 41

9.2 Borehole Abandonment.................................................................................................. 42

9.3 Surveying ........................................................................................................................ 43

9.4 Equipment Decontamination .......................................................................................... 43

9.5 Field Work Documentation ............................................................................................ 43

10. QUALITY CONTROL.................................................................................................. 43

10.1 Quality Control for Field Screened Samples.................................................................. 43

10.1.1 Processed and Unprocessed In-situ Screening Samples ....................................... 44

10.1.2 Laboratory Confirmation of Screening Samples .................................................. 44

10.2 Field Quality Control...................................................................................................... 47

10.3 Laboratory Quality Control ............................................................................................ 51

10.4 Data Usability................................................................................................................. 51

11. SAMPLE DOCUMENTATION, PACKAGING, AND CUSTODY REQUIREMENTS......................51
11.1 Sample Collection Documentation ................................................................................. 52

11.2 Field Notes...................................................................................................................... 52

11.3 Sample Packaging and Shipping .................................................................................... 52

11.4 Custody Procedures ........................................................................................................ 52

11.4.1 Field Custody Procedures ..................................................................................... 52

12. REFERENCES .............................................................................................................. 54

LIST OF TABLES IN TEXT

Text Table 2.1 PSL Selection Summary........................................................................................ 3 

Text Table 3.4.2 Summary of Background Soil Concentrations ................................................... 9

Text Table 6.2. Placement and Sampling History of Surface Water Monitoring Points............. 26

LIST OF ATTACHED TABLES

Table 1a Analytical Results: Upper Tailings Delineation Transects

Table 1b Analytical Results: Lower Tailings Delineation Transects

Table 2 Analytical Results: Background Soils

Table 3 Analytical Results: Tailings Reprocessing

Table 4 Analytical Results: Soil Borings

Table 5 Laboratory Results: Geotechnical Sampling

Table 6 Groundwater Elevations

Table 7 Analytical Results: Groundwater

Table 8 Analytical Results: Surface Water

Table 9 Analytical Results: Sediment

Table 10 Analytical Results: Investigation-Derived Waste (Soil)

Table 11 Analytical Results: Investigation-Derived Waste (Water)

Table 12 Analytical Results: QA/QC Samples

Table 13 QA/QC Validation
LIST OF FIGURES

Figure 1. Site Location Map

Figure 2. Site Layout

Figure 3. All Sampling Locations- Tailings Vicinity

Figure 4. Geologic Cross Section Locations

Figure 5. Geologic Cross Section A-A’

Figure 6. Geologic Cross Section B-B’

Figure 7. Geologic Cross Section C-C’

Figure 8. Geologic Cross Section D-D’

Figure 9. Multi-Increment (MI) Soil Sampling Results

Figure 10. Soil Boring XRF Results

Figure 11a. Upper Tailings Screening Results: Arsenic Concentrations

Figure 11b. Upper Tailings Screening Results: Lead Concentrations

Figure 12a. Lower Tailings Screening Results: Arsenic Concentrations

Figure 12b. Lower Tailings Screening Results: Lead Concentrations

Figure 13. Monitoring Well Locations

Figure 14. Groundwater Potentiometric Map

Figure 15. Surface Water and Sediment Sampling Locations

Figure 16. Surface Water Results

Figure 17. Sediment Results

Figure 18. Geotechnical Soil Boring Locations

Figure 19. Geotechnical Tailings Sample Locations

Figure 20 Tailings Reprocessing Sample Locations

LIST OF ATTACHMENTS

Attachment 1 Photoplates

Attachment 2 Borehole Logs

Attachment 3 Cultural Resource Monitoring Report

Attachment 4 Laboratory Analytical Results Attachment
5 Daily Logs

ABBREVIATIONS AND ACRONYMS

AAC Alaska Administrative Code

ADEC Alaska Department of Environmental Conservation

ADOT Alaska Department of Transportation

amsl Above Mean Sea Level

bgs Below Ground Surface

8F Degrees Fahrenheit

COC Chain of Custody

DS Discrete Sample

EE/CA Engineering Evaluation/Cost Analysis

EPA United States Environmental Protection Agency

FSP Field Sampling Plan

GPS Global Positioning System

JCO The Johnson Company, Inc.

L Liter

mg/L Milligrams per liter

mL Milliliter

μg/L Micrograms per liter

mg/kg Milligrams per kilogram

MI Multi-Increment

MS/MSD Matrix Spike/Matrix Spike Duplicate

MW Monitoring Well

NOAA National Oceanic and Atmospheric Administration

NPS National Park Service

ORP Oxidation-Reduction Potential

PE Performance Evaluation Sample

PVC Polyvinyl chloride
QAPP Quality Assurance Project Plan

RPD Relative Percent Difference

SAP Sampling and Analysis Plan

SSI Supplemental Site Investigation

SOP Standard Operating Procedure

USGS United States Geological Survey

WRST Wrangell-St. Elias National Park and Preserve

XRF X-Ray Fluorescence Analyzer
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Title: Nabesna Mine Supplemental Site Investigation Report 

Site Name: Nabesna Mine Site 

Site Location: WRST, Alaska Page 1 of 54 

1. INTRODUCTION 

The following Supplemental Site Investigation (SSI) Report details the methodology used 

in and results of the Supplemental Site Investigation performed by The Johnson Company, Inc. 

(JCO) in August 2009 at the Nabesna Mine located on the eastern slopes of White Mountain, a 

peak on the northeastern edge of the Wrangell Mountain Range within the Wrangell-St. Elias 

National Park and Preserve (WRST) at Nabesna, Alaska (the Site), as shown on Figures 1 and 2. 

The SSI was conducted in accordance with the Site-specific Field Sampling Plan (FSP) dated 

August 3, 2009, the FSP addendum dated September 2009, and the Quality Assurance Project 

Plan (QAPP) dated August 3, 2009, which together comprised the Sampling and Analysis Plan 

(SAP). 

This SSI report summarizes background information on the Site, describes field 

investigation activities, and presents the investigation results. This SSI Report is provided as a 

supporting document for the Engineering Evaluation/Cost Analysis (EE/CA) Report for the Site. 

2. SITE BACKGROUND 

The geographic location, Site contamination history, and summary of previous 

investigations and previous response actions are detailed in the EE/CA Report. 

2.1 GENERAL SAMPLING OBJECTIVES 

Previous investigations provided a substantial amount of data, but some information 

necessary for removal action selection was insufficient, outdated, or absent. This information 

was collected through additional sampling performed during the SSI. Figure 3 presents an 

overview of actual sampling conducted during the SSI. The general objectives and methods of 

the SSI were as follows. 

• Additional groundwater data were required to fully assess environmental 

contamination and transport mechanisms. These data were collected through the 

installation and sampling of eight monitoring wells (seven of which were 

sampled). The geologic logging of these boreholes provided information 

regarding the influence of geology and permafrost on groundwater and surface 

water migration. 
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• The effects of a partial response action (i.e., ditch rehabilitation completed in 

2002) on surface water quality had not been evaluated. Surface water and 

sediment quality was assessed through sampling at 23 locations. 

• The location of the Site in an area of naturally mineral-rich soil deposits required 

a thorough examination of the background characteristics of soil, sediment, and 

surface water to establish Site-specific background concentrations that could 

affect Site cleanup goals. In addition to the background surface water and 

sediment samples collected upstream of the mill, five multi-increment (MI) 

samples were collected from soils outside of areas impacted by mining activities 

to determine appropriate and representative background concentrations in soils at 

the Site. 

• Migration of the tailings had not been evaluated since the most recent delineation 

of the tailings in 1998. This delineation was updated through visual observations 

and screening analysis of metals concentrations in surficial soils at approximately 

230 locations. 

• Test pits (three in the Upper Tailings and one in the Lower Tailings) for soil 

sampling were excavated in 2004; results indicated the possibility of downward 

metals leaching from the tailings, but the depth and number of metals screened 

were limited. In the SSI, screening and laboratory analysis for metals was 

performed in eleven soil borings completed below the bottom of visible tailings. 

• No data were available regarding the potential effectiveness of reprocessing the 

tailings for gold at existing mills. Additional sampling was performed to evaluate 

potential recovery and waste generation issues. 

• In order to accurately evaluate the possibility of creating an on-site tailings 

stockpile, geotechnical analysis was performed on samples from the tailings and 

underlying soils. Samples of the underlying soils were obtained through the 

completion of 10 soil borings on the Upper Tailings. 

Concentrations of metals in soil, sediment, surface water, and groundwater at the Site 

have been compared against the more conservative (i.e., the lowest) of either the federal 
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Title: Nabesna Mine Supplemental Site Investigation Report 

Site Name: Nabesna Mine Site 

Site Location: WRST, Alaska Page 4 of 54 

from deposition by Cabin Creek. In some locations, the silt deposit has been eroded by surface 

water flow; sands and gravels are more common in these areas. Currently, Cabin Creek is not 

able to flow over the Site because the Southern Historic Ditch redirects surface water away from 

the Site. 

Two drill rigs were used at numerous locations on and outside the tailings areas for 

various components of the SSI, as described in later sections of this report. Layers of different 

soil types with depth in each boring were logged in boring logs resulting in a record of the 

surficial geology (i.e., all soil layers above bedrock) at each location; by spatially relating these 

recorded geological layers, cross-sectional views of the surficial geology were created (Figures 4 

through 8). Individual boring logs are presented in Attachment 2. As shown on Figure 5, cross 

section A-A’ is oriented approximately west-southwest to east-northeast downhill through the 

length of the Upper and Lower Tailings. Cross section B-B’ is oriented south-southwest to 

north-northeast and captures all monitoring wells and geologic borings completed adjacent to the 

north side of Nabesna Road. Cross section C-C’ is approximately perpendicular to cross section 

A-A’ and incorporates all monitoring wells installed in the Lower Tailings, connecting to cross 

section B-B’ at MW-J1. Cross section D-D’ has an approximately south to north orientation 

bisecting the Upper Tailings. 

Cross section A-A’ has the most continuous and complete record of the surficial Site 

geology because it incorporates numerous borings located across both the Upper and Lower 

Tailings. The more prominent features of the Site surficial geology include the following points. 

• A layer of silt immediately underlies the tailings and the area surrounding the tailings 

where borings were completed, including above apparently higher energy depositional 

environments of talus and fluvial sands and gravel such as those beneath southwestern 

portion of the Upper Tailings. 

• Permafrost in silt was observed in only three borings, all outside the tailings area 

apparently where the upper geologic profile contained silt, as shown at boring location 

MW-J2 in cross section A-A’, location MW-J8 in cross section B-B’, and MW-J5 in 
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Title: Nabesna Mine Supplemental Site Investigation Report 

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Site Location: WRST, Alaska Page 5 of 54 

cross section C-C’. Permafrost was not detected at boring location MW-J1 northeast and 

outside of the tailings area on cross section C-C’ presumably because there are welldrained and relatively more permeable sand and gravel deposits from the ground surface 

to approximately 30 feet below ground surface (bgs) and the water table is relatively deep 

(approximately 45 feet bgs). 

• Sand and gravel underlie the silt throughout the area of investigation except 

downgradient of the Lower Tailings (boring location MW-J2, shown in cross section AA’), where the upper silt unit increases in thickness to approximately 30 feet. The silt 

unit at this location is of greater thickness than in other investigated areas and is situated 

in an area of significantly lower topographic slope. 

• A unit of well-sorted, fine sands underlies the sand/gravel/silt units only in the area of the 

Lower Tailings, apparently southeast of Nabesna Road (cross section A-A’). Where the 

fine sand unit was encountered in boring locations MW-J4 and MW-J2, the sands were 

flowing upward into the drilling casing as a result of high water pressure confined in this 

unit. 

• In addition to the fine sand encountered only in the Lower Tailings area, a dense silty 

clay unit was observed beneath the fine sand, emphasizing the change in depositional 

environments southeast of Nabesna Road (cross section A-A’). 

• Three borings northwest of Nabesna Road, MW-J6, MW-J7, and MW-J8, encountered 

limestone bedrock, which is assumed to also underlie the silty clay in the area of the 

Lower Tailings, but because the thickness of the silty clay is unknown, the depth to the 

bedrock in the Lower Tailings area is also unknown (the presumed location is shown on 

the cross sections). 

3. BACKGROUND SOIL SAMPLING 

3.1 PURPOSE AND GENERAL APPROACH: BACKGROUND SOIL SAMPLING 

To establish background soil concentrations, MI surficial soil samples were collected 

from five locations above or across the slope from the Site, as shown on Figure 9. The MI 

method was selected because it provides the most accurate representation of the soils available to 

an ecological receptor, is well suited to surficial soil sampling, and is likely to be the method 
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Title: Nabesna Mine Supplemental Site Investigation Report 

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Site Location: WRST, Alaska Page 6 of 54 

used for cleanup verification sampling if a removal action is implemented. Although the Site is 

relatively remote, the Nabesna Road, former mine operations (including a tram, mill, and adits), 

and associated living areas have resulted in human and/or mine related impacts to the surficial 

soils in several directions around the Site; locations with no visible disturbance were sought as 

suitable background MI sampling locations. Each location encompassed a total area of 

approximately 0.25 acre, which is similar to the smallest home range of a typical ecological 

receptor (a shrew or other small burrowing mammal). Preliminary field observations and 

discussions of geology indicated that native soils near the ground surface in the Site area were 

likely to be composed of fluvial, alluvial, and talus deposits of variable thicknesses depending on 

proximity to the cliff face of White Mountain (as discussed above in Section 2.2, it was later 

determined that silt was the dominant surface soil at the Site, deposited either by water or wind). 

Since the surficial soil types under the tailings had the potential to vary significantly, efforts were 

made to collect at least one background MI sample that would be representative of each potential 

soil type. 

The presence of a mineralized zone in the cliff face of White Mountain above the Site has 

created the geologic formation that was ultimately mined for gold. The mined zone above the 

Site is composed of massive sulfides (primarily pyrite containing gold, pyrrhotite, arsenopyrite, 

minor chalcopyrite, sphalerite, and galena) and surrounding skarn rock; in this case, the term 

“skarn” refers to a localized zone of intrusive quartz diorite and host limestone that was heavily 

altered through contact metamorphism at the time of the intrusion. Because this skarn rock is 

relatively rare in the general area, it may have a unique geochemical influence on the soils in the 

fall zones beneath the mine. As such, the area providing representative background sampling 

locations was necessarily limited to soils immediately around, but not impacted by, the Site. 

3.2 LOCATIONS: BACKGROUND SOIL SAMPLES 

The five targeted background soil sampling locations were host to soils likely composed 

of the three primary types of local bedrock specific to the area surrounding the tailings: 1) unmineralized talus slopes largely composed of intrusive granodiorite and quartz-diorite mixed 

with minimal limestone scree; 2) mineralized talus slopes largely composed of skarn bedrock 

from the contact region of the intrusive bedrock and the host Nabesna limestone; and, 3) fluvial 
AR000113

 

 

 

 

Title: Nabesna Mine Supplemental Site Investigation Report 

Site Name: Nabesna Mine Site 

Site Location: WRST, Alaska Page 7 of 54 

deposits from channels of Cabin Creek that consist of organic material, silt, and sand and gravel 

from the extensive Wrangell Lava cap bedrock that overlies the Nabesna Limestone and from 

other rock types present on the hillside. Soil presumed to be primarily influenced by deposition 

of the widespread limestone of the Nabesna River valley (such as the region north of the mine 

adits) was not sampled as a representative background soil because both local topography and 

soil boring samples showed little indication of limestone-only deposition in the area beneath and 

surrounding the tailings. 

The locations of the five MI sample areas, as surveyed with a global positioning system 

(GPS) hand-held unit with sub-meter accuracy, are shown on Figure 9. MI sample locations SSJ1 and SS-J2 were located west of, and at a higher elevation than, the Upper Tailings. These 

areas were within the first of the target zones identified above (un-mineralized talus slopes). SSJ1 was located downslope from primarily intrusive quartz-diorite outcrop with minimal influence 

from the limestone cliff further to the south and the mineralized contact zones to the north. SSJ2 was located on steep slopes below outcrop that exhibited a region of un-mineralized contact 

between intrusive quartz-diorite and altered host limestone (Photoplate 11). 

MI locations SS-J3 and SS-J5 were in the second target zone identified above 

(mineralized talus slopes with skarn bedrock and limestone). Sample SS-J3 was collected from 

sandy soils at a similar elevation as the top of the Upper Tailings, whereas SS-J5 was located at a 

lower elevation to account for the likelihood of soil deposition from fluvial deposits mixed with 

more mineralized talus and alluvium. SS-J5 is considered to most accurately represent the native 

soil deposits under the mine tailings, including the materials from the skarn fall zone and the silt 

blanket deposit that underlies the tailings. 

Sample location SS-J4 was within the third targeted zone (the expected historical channel 

paths and floodplains of Cabin Creek), but significantly upstream of creek depositional areas that 

could be influenced by the tailings. Soils at this location were fluvial, consisting of organic 

material, silt, and sand from intrusive quartz-diorite and Wrangell Lava cap bedrock. 
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Title: Nabesna Mine Supplemental Site Investigation Report 

Site Name: Nabesna Mine Site 

Site Location: WRST, Alaska Page 8 of 54 

3.3 METHODS: BACKGROUND SOIL SAMPLING 

At each background location, a handheld GPS unit was used to mark four corners of an 

approximate 100 foot x 100 foot square (approximately 0.25 acre) sampling area (the positions 

of the corners are illustrated on Figure 9. Within the sampling area, an approximate 9 foot x 9 

foot grid was created and a sample increment was collected from the center of each grid cell, for 

a total of 81 increments per sampling area. Sample increments were generally collected from the 

top 6 inches of soil using a stainless steel spoon or trowel in order to retrieve an approximately 

equal mass of soil from each location, and placed in a 3.8 liter (1 gallon) polyethylene container 

for transport to the laboratory. Some increments were collected after using a hand auger or 

trowel to remove up to 1.5 feet of organic material from the surface to expose the soil. 

Sample SS-J3 was collected in triplicate by performing the sampling process three times. 

The SS-J3 area was first sampled on August 17, 2009. Duplicate and triplicate samples (SSDUP and SS-TRP) were collected simultaneously on August 18, 2009, using dedicated sample 

equipment and containers. All sampling equipment was decontaminated between decision units. 

The samples were processed by TestAmerica in North Canton, Ohio, using a subsampling 

method and analyzed via EPA Methods 6020 and 7470A for the 14 target metals in soil. 

3.4 RESULTS: BACKGROUND SOIL SAMPLING 

Analytical results of the five background soil locations are provided in Table 2. All of 

the soil samples contained arsenic at levels above the Federal Industrial Regional Screening 

Level (RSL) level of 1.6 milligrams per kilogram (mg/kg); however, to account for background 

levels in Alaska that are typically above this level, the ADEC Level II Soil Cleanup Standard of 

4.5 mg/kg has been used for comparison instead. This practice is accepted in several states, and 

is reasonable for Alaska as a preliminary screening level because ADEC also requires that 

background arsenic levels be evaluated where anthropogenic impacts are suspected (ADEC, 

2008 and ADEC, 2009). Arsenic was present in four of the five samples at concentrations from 

24.7 to 130 mg/kg, exceeding the ADEC soil screening level of 4.5 mg/kg. In sample SS-J4, 

collected from alluvium south of the Upper Tailings, the arsenic concentration (estimated at 1.3 

mg/kg by the laboratory), was below the ADEC screening level. Concentrations of all other 
AR000115

 

 

Title: Nabesna Mine Supplemental Site Investigation Report 

Site Name: Nabesna Mine Site 

Site Location: WRST, Alaska Page 9 of 54 

targeted metals were below PSLs in all samples. The ranges of all 14 targeted elements in soil in 

the background samples are summarized in Text Table 3.4.2, below. 

Text Table 3.4.2 Summary of Background Soil Concentrations 

Analyte Concentration Range 

(mg/kg) 

Location of Highest 

Concentration 

Location of Lowest 

Concentration 

Arsenic 1.3 – 130 SS-J5 SS-J4 

Cadmium 0.21 – 1.87 SS-J3 SS-J1 

Chromium 12.9 – 110.0 SS-J1 SS-J4 

Cobalt 3.9 – 11.5 SS-J2 SS-J4 

Copper 17.8 – 532-7 SS-J3 SS-J4 

Iron 9,270 – 30,400 SS-J5 SS-J4 

Lead 1.1 – 83.4 SS-J3 SS-J4 

Manganese 150 – 1,280 SS-J2 SS-J4 

Mercury 0.017 – 0.085 SS-J5 SS-J4 

Nickel 10.0 – 50.1 SS-J1 SS-J4 

Selenium 5.1 – 5.3 SS-J1 SS-J4 

Silver 0.32 – 2.1 SS-J5 SS-J2 

Vanadium 14.5 – 31.8 SS-J4 SS-J3 

Zinc 23.1 – 363.0 SS-J2 SS-J4 

Upon review of the surficial geology at the Site, which includes silt immediately beneath 

the tailings and north of the tailings Site, it is apparent that the alluvial sample from SS-J4 is 

unlikely to be similar to the natural surficial soils at the Site. Thus, there are two identified target 

zones remaining that could be considered to be representative of soil types at the Site: the unmineralized talus slopes (SS-J1 and SS-J2) and mineralized talus slopes (SS-J3 and SS-J5) as 

described above in Section 3.2. However, the presence of silt immediately beneath the tailings 

indicates that a fourth target zone should be considered: one that is likely to contain silt from the 

same source as that at the Site. Since silt was observed at the surface in a significant majority of 

the borings at the Site, it is considered a blanket deposit that resulted from water or wind 

deposition. Extrapolating from cross section D-D’, in which silt is present across the entire 

width of the Upper Tailings, it is expected that sampling location SS-J5 would also have silt at 

the surface, since it is in an area that does not appear to be affected by stream channels and is at a 

similar elevation to the ground surface of the borings that comprise cross-section D-D’. In 

addition, SS-J5 is located within the relatively narrow fall zone of the mineralized/skarn rock, 

and is the location nearest to the Site tailings area. However, the sampling area was chosen 

specifically because it was undisturbed and did not appear to have been impacted by mining 
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Title: Nabesna Mine Supplemental Site Investigation Report 

Site Name: Nabesna Mine Site 

Site Location: WRST, Alaska Page 10 of 54 

activities. Since the area is approximately 250 feet away from the closest visible tailings, not 

immediately downslope of the tailings, and separated from the tailings by the northern historic 

ditch, it is unlikely that it has been impacted by tailings. As such, SS-J5 is considered the soil 

sample that is most representative of background conditions at the Site. 

Although the background samples were selected to include a range of soil types in the 

general vicinity of the tailings, it is not appropriate to average all of the MI area results for each 

metal to derive a representative background concentration. The MI sampling method establishes 

a statistically defensible “average” exposure concentration for each of the MI areas, which are 

based on the smallest home range of a typical ecological receptor that would be expected to be 

present at the Site. At this Site, the combination of erosional deposition from the skarn deposits 

upgradient of the tailings and the silt deposits present on the lower slopes greatly influences the 

metals concentrations that are naturally present at the Site. The SS-J1, SS-J2, and SS-J3 MI 

areas were located at elevations too high on the mountain to include the silt deposit, and the SSJ1 and SS-J2 locations are not within the fall zone of the skarn deposits. The SS-J4 surficial 

geology differs greatly from the geology immediately beneath the tailings because of the 

significant influence of erosion and deposition by Cabin Creek. The extent of the silt deposit 

beneath the tailings was characterized only after the investigation was complete and the boring 

logs were reviewed (as discussed in Section 2.2). As such, it was not possible to focus all of the 

MI sampling locations in areas that were considered to be more representative of soils beneath 

the tailings, although Figure 9 illustrates that the locations in which the three criteria for 

representative background (i.e., those that included silt, were within the skarn rock fall zone, and 

were not in areas of tailings impact) can be met are limited to a relatively narrow expanse of land 

that parallels the Nabesna Road to the north of the tailings, starting at the southern end with the 

SS-J5 sampling area. 

Although the background concentration for arsenic is significantly higher than the PSL, it 

is considered to be representative because of the mineralized nature of the Site and the presence 

of Nikolai Greenstone at the Site. As Health Canada explains in their risk assessment guidance, 

Greenstone belts and other geologic deposits that may contain gold ore are typically high in 
AR000117

 

 

Title: Nabesna Mine Supplemental Site Investigation Report 

Site Name: Nabesna Mine Site 

Site Location: WRST, Alaska Page 11 of 54 

arsenic, both in rock and naturally occurring soil at the Site (Health Canada, 2004). The Health 

Canada guidance states, “prospecting for mineral deposits is often accomplished by surveying 

soils for anomalously high arsenic levels.” This type of prospecting is described in a 1983 report 

completed by the State of Alaska to assess the mineral potential of a proposed subdivision in an 

area of Fairbanks, Alaska (Clautice, 1983). The report states that arsenic and antimony are most 

indicative of lode gold mineralization in the Fairbanks district, and arsenic in soil samples (at a 

location where no mine was present), ranged from10 ppm to 149 ppm, and indicates that these 

values are similar to a 1982 study at Ester Dome in which arsenic in samples ranged from18 ppm 

to 148 ppm. Further evidence that the use of 130 ppm as a reasonable background arsenic 

concentration is presented in the Health Canada guidance, which explains, “[i]n Yellowknife, 

[Northwest Territories], the natural soil-borne levels of arsenic average approximately 150 ppm” 

because the city is located on a greenstone belt (Health Canada, 2004). This background 

concentration is reflected in the Northwest Territories’ “Environmental Guideline for 

Contaminated Site Remediation,” which states that the remediation objectives for residential and 

industrial soil in Yellowknife are 160 mg/kg and 340 mg/kg, respectively based on the 

assumption yard soil that is accessible for exposure for 5 months of the year (Mackenzie Valley 

Review Board, 2003). 

4. DELINEATION OF TAILINGS IMPACTS 

4.1 PURPOSE AND GENERAL APPROACH: DELINEATION OF TAILINGS 

IMPACTS 

The most recent effort to delineate the areal extent of tailings was performed by NPS in 

the late 1990s, following an earlier depth and metals assay survey between 1979 and 1981 

(WGM, 1981). Since that time, tailings may have been transported through erosion to the 

ground surface or to surface water sediments beyond previously mapped areas. In addition, 

sampling conducted during the excavation of test pits by NPS in 2004 indicated that metals may 

have leached downward from the tailings. 

4.1.1 PURPOSE AND GENERAL APPROACH: AREAL EXTENT OF TAILINGS 

IMPACTS 

Surficial and subsurface sampling was conducted during the SSI to update the 

characterization of the areal and vertical extent of tailings impact. On the ground surface, the 
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Title: Nabesna Mine Supplemental Site Investigation Report 

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Site Location: WRST, Alaska Page 12 of 54 

tailings were first delineated visually, by mapping the boundary of the unvegetated tailings area 

with a GPS unit with sub-meter accuracy. After completing this visual delineation, surficial soils 

on all sides of the tailings were screened for metals in north-south transects with a portable 

Innov-X Alpha X-ray fluorescence (XRF) metals analyzer to evaluate the extent of tailingsimpacted soil. Use of the XRF to screen metals concentrations in soil allowed for screening of a 

large number of samples rapidly, which also allowed the length and spacing of the transects to be 

determined in an adaptive manner. The XRF operates on the principle that X-rays emitted when 

electrons change their configuration are characteristic of a given element. Calibration curves 

within the instrument allow it to calculate element concentrations from relative intensities of the 

X-rays. At some locations, duplicate samples were submitted for laboratory confirmation 

analysis to verify the reliability of the field screening results. 

4.1.2 PURPOSE AND GENERAL APPROACH: VERTICAL EXTENT OF 

TAILINGS IMPACTS 

Subsurface sampling to determine the extent of metals leaching was performed in 11 

borings located throughout the Upper and Lower Tailings (Figure 10). In each boring, samples 

were collected at approximate 1-foot intervals to an approximate depth of 5 feet below the 

visible bottom of the tailings. Sample intervals were selected in the field in order to evaluate 

whether metals concentrations are influenced by soil type as well as depth. 

4.2 SAMPLING LOCATIONS: DELINEATION OF TAILINGS IMPACTS 

4.2.1 SAMPLE LOCATIONS: AREAL EXTENT OF TAILINGS IMPACTS 

Surficial soils were analyzed at 232 locations along 20 transects, which were positioned 

75 to 200 feet apart across the visible tailings area, oriented approximately north-south (Figures 

11a and b, and 12a and b). XRF screening analysis for the 14 targeted metals in soil (Tables 1a 

and 1b) was performed at 6 to 19 locations along each transect, beginning inside the visible edge 

of the tailings and proceeding outwards until a boundary of the tailings-impacted soil was 

observed, based on visual observations and iron, arsenic, and lead concentrations. In general, 

transects were split on the north and south sides to not include visible tailings, which were 

already known to be impacted by metals. All sample locations were recorded with a sub-meter 

accurate GPS. 
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In addition to the samples collected along the transects, surficial samples were collected 

throughout the course of the investigation at locations where soils having the appearance of 

tailings were observed; locations of these additional samples were above the mill building 

(TRAM, Figures 11a and 11b), in between the Upper and Lower Tailings (DS-113 through 117, 

Figures 12a and 12b), and adjacent to Cabin Creek downstream of the tailings (BANK, Figures 

12a and 12b). 

4.2.2 SAMPLE LOCATIONS: VERTICAL EXTENT OF TAILINGS IMPACTS 

The vertical extent of tailings impact in soils beneath the tailings was evaluated through 

subsurface sampling performed in 11 soil borings (Figure 10). Metals XRF screening was 

performed on samples from eight borings (SB-J5, J6, J8, J9, J11, J12, J15, and J17) completed in 

the Upper Tailings and three borings (MW-J3, MW-J4-D, and SB-J2) located in the Lower 

Tailings. Boring locations were selected for adequate spatial coverage in addition to 

geotechnical sampling or monitoring well installation. 

Soil samples from certain borings were selected for XRF screening analysis after the 

completion of all soil borings. XRF screening was performed on soil samples from borings 

where a clear visual base of the tailings could be observed, where the tailings did not appear to 

have been moved since their initial deposition (e.g., during construction of the switchbacks 

across the Upper Tailings), and where recovery in the split spoons was acceptable. 

4.3 METHODS: XRF SCREENING 

The successful delineation of the extensive horizontal and vertical area of the tailings 

relied primarily on the XRF screening. The recommended drying and sieving procedures 

described in EPA Method 6200 for XRF analysis were followed to ensure that samples were 

adequately homogenized and, therefore, the subsamples analyzed by the XRF and the laboratory 

would have a similar composition. At locations where a sample was collected for processing, 

approximately 120 mL of soil was removed and placed in a Ziploc bag for transport to a field 

laboratory located at Devil’s Mountain Lodge, approximately 3 miles from the Site. Since the 

outside weather conditions were slightly above freezing with high humidity, and the remoteness 

of the Site did not allow for a field laboratory to be set up in a temperature-controlled facility 

with a constant electricity supply, the processed XRF and corresponding laboratory confirmation 
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samples were dried in a toaster oven set at 150 degrees (the lowest setting, which minimized the 

loss of mercury to the extent possible). The processing step involved breaking the dried samples 

apart with a mortar and pestle, sieving them with a No. 20 screen (the screen size was chosen 

because it is typically used for sediments, which were also processed and analyzed in a separate 

part of the investigation for sediment analysis), and retaining the passing fraction for analysis 

(the coarse fraction was discarded). The samples that were processed in this manner and 

screened using the XRF were called “processed XRF” samples. Following processing of a small 

percentage of the planned number of screening samples, it became clear that drying and sieving 

all screening samples would significantly limit the number of samples analyzed because the 

generator that powered the toaster oven could not be operated for as many hours as would be 

necessary to dry all of the samples. Since the purpose of this portion of the investigation was to 

fully delineate the extents of the tailings, it was imperative to screen as many samples as possible 

while in the field. Therefore, a field study was conducted between August 19 and 21, 2009, to 

evaluate the difference between using the XRF to screen processed soils versus analyzing soils 

in-situ at the Site. In-situ screening was conducted by removing the layer of duff or other 

organics off the ground surface, then pressing the XRF to the soil without further disturbance and 

recording the field result. Concentrations of both lead and arsenic in processed XRF samples 

were greater than the results of the in-situ XRF samples by a median factor of 1.5. This 

difference was judged to be acceptable given the Site conditions. The decision was made to 

screen the majority of samples in-situ, allowing an immediate decision regarding the length of 

the transect, in conjunction with collection and processing of approximately 10 percent of these 

samples for additional XRF screening at the field laboratory at Devil’s Mountain Lodge (i.e., the 

“processed samples”). 

Half of all processed samples (corresponding to 1 out of every 20 surficial sample 

locations) were transferred to a 60 mL plastic jar and submitted TestAmerica in North Canton, 

Ohio for confirmatory analysis of the 14 target metals in soil (arsenic, cadmium, chromium, 

cobalt, copper, iron, lead, manganese, mercury, nickel, selenium, silver, vanadium, and zinc) by 

EPA Methods 6020 and 7471 (mercury). All of the confirmation samples sent to the laboratory 
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were subsampled from processed XRF samples (i.e., the dried and sieved fraction of the original 

sample). 

4.3.1 METHODS: AREAL EXTENT OF TAILINGS IMPACTS 

At each location, soil was generally accessed by scraping vegetation from the ground 

surface using a trowel. For in-situ screening samples, the XRF analyzer was then placed directly 

on the ground in contact with the soil, and a reading was performed for 2 minutes. At some 

locations, recent overflow of the Southern Historic Ditch and Cabin Creek had deposited several 

inches of grey sand over a large area. At these locations, a trowel or hand auger was used to 

remove the recently deposited sand, and material in the layer below was analyzed. At locations 

where a thick layer of organic material was present, a hand auger was used to expose soil 

beneath the organic layer for analysis. 

4.3.2 METHODS: VERTICAL EXTENT OF TAILINGS IMPACTS 

Continuous cores of soil in each boring were collected from the ground surface until a 

minimum depth of 5 feet below the visible bottom of the tailings using a 2-foot split spoon 

sampler (tailings were typically less than 2 feet thick, although at some locations in the Upper 

Tailings, they were mixed with soil to deeper depths). After the soil types in each split spoon 

were logged, the contents of the spoon were divided into individual plastic bags, with a separate 

bag for each soil type indentified in the spoon. Following review of the boring logs, one bag of 

soil from each 1-foot depth interval was selected for XRF screening, resulting in five to six 

samples per boring, with a range of soil types represented, although a greater percentage of finegrained soils were selected to evaluate their ability to retain or retard migration of metals through 

sorption or lower permeability. 

One out of every five processed samples was transferred into a 60 mL plastic jar and 

submitted TestAmerica in North Canton, Ohio, for confirmatory analysis of the 14 target metals 

in soil (arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, 

selenium, silver, vanadium, and zinc) using EPA Methods 6020 and 7471 (mercury). 
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4.4 RESULTS: DELINEATION OF TAILINGS IMPACTS 

4.4.1 RESULTS: AREAL EXTENT OF TAILINGS IMPACTS 

Laboratory and XRF screening results from the 234 surficial soil samples are presented in 

Tables 1a and 1b. In general, the only target metals/metalloids that appeared to be consistently 

elevated compared to background (SS-J5) concentrations were iron, lead, and arsenic. Although 

some metals were detected above ADEC screening levels in soil samples, areas of visible tailings 

contained consistently elevated iron, lead, and arsenic levels. Iron concentrations were reported 

between 885 mg/kg and over 100,000 mg/kg (the maximum calibration range of the instrument). 

Because iron concentrations in the tailings regularly exceeded the maximum calibration range of 

the XRF, lead and arsenic were chosen as target elements to delineate the migration of tailings 

impacts. XRF arsenic screening concentrations ranged from less than 3 mg/kg in organic soils to 

approximately 3,900 mg/kg in soil adjacent to the visible tailings. Lead concentrations ranged 

from less than 4 mg/kg in organic soils adjacent to the tailings to approximately 4,400 mg/kg 

within the visible tailings. Results from in-situ XRF screening analysis of lead are shown on 

Figure 11a and 11b and arsenic are shown on Figures 12a and 12b for the Upper and Lower 

Tailings, respectively. The areal extent of visibly-impacted soils (i.e., where tailings were 

observed mixed with soils either at the surface or immediately beneath the surface) is shown on 

Figures 11a and b and 12a and b. 

The use of visual observations to delineate the areal extent of tailings was chosen after 

comparing these observations with areas delineated by arsenic and lead concentrations above the 

levels in the most representative background sample (SS-J5, with an estimated arsenic 

concentration of 130 mg/kg and a lead concentration of 68 mg/kg). In general, these three 

methods provided similar results. The concentration of arsenic from the MI soil sample at 

location SS-J5 was chosen to define arsenic impacts because using the ADEC screening level for 

arsenic of 4.5 mg/kg for comparison resulted in nearly all of the sampling locations, including all 

but one background location, considered “impacted”, which is an unreasonable conclusion that 

does not account for naturally-occurring concentrations. 

In the Upper Tailings, the north-south migration of the tailings has largely been 

controlled by the Site topography and the Northern and Southern Historic Ditches. The ground 
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surface rises at the southern edge of the Upper Tailings, and few concentrations of lead above the 

ADEC screening level or arsenic above the background level (assumed to be the concentration at 

SS-J5) were observed beyond the southern visible edge of the Upper Tailings. No visible 

tailings were observed inside the Southern Historic Ditch. North of the Upper Tailings, tailings 

were observed within the Northern Historic Ditch, and concentrations of lead and arsenic above 

background levels were observed in ditch excavation spoil (locations DS-064, DS-079, and DS104) and sample locations as far as 100 feet north of this ditch (DS-083). 

Soil screening results and visual observations showed no indication of northerly tailings 

migration beyond the visible northern edge of the Lower Tailings. However, shallow soils 

having the appearance of tailings were observed along the westernmost transect through the 

Lower Tailings, from the visible edge of the surficial tailings until the Southern Historic Ditch 

(i.e., in samples DS-121 to DS-128). Additional transects completed further to the east showed 

apparent tailings deposits in shallow soil extending only partway to the Southern Historic Ditch, 

and no visual evidence of tailings was found in the ditch. 

At the eastern end of the Lower Tailings, the trails created by game, all-terrain vehicles, 

and, possibly, the drill rig used to install MW-2 in 1998, have permitted the migration of a thin 

veneer of tailings in numerous long, narrow fingers. Based on the lack of visible tailings beyond 

the easternmost transect and the observation that the arsenic and lead concentrations declined 

considerably over the approximately 200 feet between the easternmost and next nearest transects, 

the extent of the Lower Tailings is considered to have been fully delineated. This does not 

preclude the possibility of small, localized, or covered deposits, but these are likely to be 

extremely small with respect to the area of tailings that has been delineated. 

During the SSI, small, isolated deposits of tailings were discovered by visual observation 

and XRF soil screening. Results of the five samples collected from the vegetated area between 

the Upper and Lower Tailings (samples DS-113 to DS-117; see Figures 12a and b) indicate that 

tailings may be present but covered with vegetation in the area between the Upper Tailings and 

Lower Tailings. In the vicinity of these samples, the ground surface was uneven and appeared to 
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have been redistributed by heavy machinery. The soils analyzed in this area did not have the 

orange color distinctive of tailings, but the homogeneous appearance of these soils distinguished 

them from other nearby native soils. In addition, mineralized waste rock may have been 

deposited beneath the tram lines extending up White Mountain from the mill building. One soil 

sample having the appearance of tailings was collected beneath the tram line approximately 400 

feet northwest of the mill building (TRAM, see Figures 11a and 11b). XRF screening of this 

sample showed lead and arsenic concentrations at more than ten times the background levels 

(1,783 mg/kg lead and 1,853 mg/kg arsenic). In addition, lead and arsenic were detected at 

2,774 mg/kg and 1,989 mg/kg, respectively, in a sample (BANK) collected approximately 1 mile 

east of the Lower Tailings near SW-J23 (see Figures 12a and 12b). These results are in 

agreement with those previously reported by the USGS (sample 6NA025), which sampled this 

isolated tailings deposit in 1999. 

4.4.2 RESULTS: VERTICAL EXTENT OF TAILINGS IMPACTS 

Results from the XRF screening of subsurface soils are presented in Table 4. Lead and 

arsenic results from the XRF screening analysis are depicted on Figure 10 and on individual 

boring logs in Attachment 2. Among the list of targeted metals (arsenic, cadmium, chromium, 

cobalt, copper, iron, lead, manganese, mercury, nickel, selenium, silver, vanadium, and zinc), 

only lead, arsenic, and copper were found to exceed ADEC soil screening levels at any locations. 

Furthermore, copper was limited to one exceedance, in sample SB-J8 (6.6-7.3’). Therefore, as 

with the areal tailings delineation, focus is given to lead and arsenic in assessing the extent of 

leaching beneath the tailings. 

In general, lead concentrations in soils beneath the tailings were below ADEC screening 

levels. Where detected, lead concentrations did not follow a trend indicative of transport by 

leaching (i.e., no significant decline in concentration was observed with depth), nor was there a 

discernable pattern to the areal distribution of lead concentrations, except that levels were highest 

in silty soils below the southern portions of the Upper Tailings. The only location where lead 

concentrations were above ADEC soil screening levels immediately below the tailings was at 

SB-J5, between 1 and 3 feet bgs, but it appears that tailings have been mixed into soils to a depth 
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of approximately 4 feet bgs at this location. Therefore, lead does not appear to have significantly 

leached from the tailings into underlying soil. 

At some locations (e.g., SB-J9, MW-J4, and SB-J2; see Figure 9), there was a trend of 

decreasing arsenic with depth; however, this was not the case at all locations. Additionally, 

arsenic concentrations remained relatively high (above 50 mg/kg) in some lower depths, such as 

at SB-J8, where the arsenic levels showed little decrease between 7 and 12 feet bgs or MW-J3, 

where concentrations were highest at 5 to 6 feet bgs. In all samples collected, the arsenic 

concentration or detection limit was significantly greater than the ADEC screening criterion of 

4.5 mg/kg, which again suggests that the use of the background arsenic result is appropriate for 

delineating tailings impacts. In general, arsenic concentrations were higher in silty layers 

relative to layers composed of sand or gravel. In the Upper Tailings, a total of eight soil borings 

were completed, and of these, arsenic concentrations immediately beneath the tailings were 

below the background level of 130 mg/kg at three locations. At the remaining five borings 

beneath the Upper Tailings, the arsenic concentrations declined to less than 130 mg/kg within 1.8 

feet below the bottom of tailings. Among all borings on the Upper Tailings, the average depth of 

impact as delineated through a comparison to the background concentration of 130 mg/kg was 

0.8 foot. In the Lower Tailings, a total of three soil borings were completed, and in one of these 

the arsenic concentration immediately beneath the tailings was below 130 mg/kg. In the other 

two borings, the arsenic concentrations declined to below 130 ppm between 1.8 and 1.9 feet. On 

average, the depth of tailings impacts to the soil beneath the Lower Tailings is estimated at 1.2 

feet. 

5. GROUNDWATER INVESTIGATION 

5.1 PURPOSE AND GENERAL APPROACH: GROUNDWATER INVESTIGATION 

5.1.1 PURPOSE AND GENERAL APPROACH: MONITORING WELLS 

In order to determine the extent of dissolved metals transport in groundwater beneath the 

tailings, monitoring wells (including one shallow and deep monitoring well couplet) were 

installed at seven locations on or adjacent to the tailings. Where permafrost was encountered, 

the soils collected above the permafrost were inspected for signs of water that would indicate a 

perched water table and a potential need for a well both above and below the permafrost. 
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However, the presence of substantial water above the permafrost was not observed. Instead, all 

wells were installed with screens that crossed or were immediately below the apparent water 

table to collect samples of the groundwater nearest the tailings, except at one location (MW-J4) 

where a deep well was coupled with a water-table well to evaluate potential impacts to deeper 

groundwater beneath a possible confining layer of silt. 

5.2 LOCATIONS: GROUNDWATER INVESTIGATION 

5.2.1 LOCATIONS: MONITORING WELLS 

All monitoring well locations are shown on Figure 13 and the total well depths with 

respect to the surficial geology are depicted in Figures 5 through 8. Well locations were selected 

to create two transects perpendicular to the presumed direction of groundwater flow (to the east). 

A part of each transect was located on the Upper or Lower Tailings to evaluate potential impacts 

from surface water infiltration through the tailings. The eastern transect (locations MW-J3 

through J5) approximately bisected the Lower Tailings from north to south. At the MW-J4 

location, the top of the screen at the “D” (deep) well was installed approximately 18 feet 

below the bottom of the screen at the co-located “S” (shallow) well, which was screened 

at the water table. 

The western transect (locations MW-J6 through J8) was located near the base of the 

Upper Tailings. The water table at MW-J7 was not crossed during drilling; instead, dry, gray 

limestone was encountered from 35 feet to 44 feet bgs. MW-J7 was completed with a 

monitoring well to confirm the absence of the water table above bedrock at this location. MWJ6, drilled after and located uphill from MW-J7, was abandoned and filled with bentonite grout 

after drilling through dry overburden followed by dry, gray limestone from 47.5 to 52.5 feet bgs. 

An additional well, MW-J2, was installed downgradient of the Lower Tailings to evaluate 

groundwater impacts at an increased distance from the tailings. A background well, (MW-J1) 

was installed along the Nabesna Road at a location presumed to be unimpacted by tailings; its 

location was also influenced by ease of access from the Nabesna Road. 
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5.3 SAMPLING AND ANALYTICAL PROCEDURES: GROUNDWATER 

INVESTIGATION 

5.3.1 SAMPLING AND ANALYTICAL PROCEDURES: WELL INSTALLATION 

Well installation occurred over a 13-day period between August 11 and August 23, 2009. 

All borings were drilled by Denali Drilling of Anchorage, Alaska, using an air-rotary trackmounted rig or a hollow-stem auger track-mounted rig (see Photoplates 1 and 2 in Attachment 

1). The air rotary method incorporated a 4.5-inch outer diameter casing that was advanced 

slightly behind an underreamer bit, which expanded to a 5-inch outside diameter when the drill 

rod was rotated clockwise beneath the casing. Cuttings were blown via compressed air up the 

inside of the casing and were contained in a drum using a diverter and hose or, alternatively, 

were shoveled from the ground into drums. Soil samples for observation were collected by 

removing the underreamer bit, lowering a 2-foot long, 3-inch diameter split-spoon sampler to the 

bottom of the boring and hammering it into the soil with repeated 30-inch drops of a 340-lb 

hammer attached to a pulley rope. The hollow stem auger method is described in Section 8.1.3. 

Continuous soil sampling was conducted for the first 25 feet of each boring, then every 5 

feet thereafter. Once the soil sample was collected, the split spoon was lifted to the surface and 

opened to allow for stratigraphic logging, soil and rock sample collection, inspection for the 

presence and thickness (or absence) of permafrost, evaluation of the potential for and location of 

perched groundwater on top of the permafrost, and observation of the approximate location of 

the water table. All field notes were documented on field logs, which were used to create the 

final boring logs provided in Attachment 2. The wells were completed by installing 2-inch inner 

diameter, pre-packed, 0.010-inch slotted polyvinyl chloride (PVC) well screens of 10-foot 

lengths attached to PVC riser that extended above the ground surface. Screens were set from 

approximately 5 to 15 feet below the water table, as drilling conditions permitted, to ensure 

sufficient water would be present for sampling in all seasons. A sand pack was installed to at 

least 2 feet above the top of the screen and a bentonite clay plug was installed to at least 1 foot 

above the top of the sand. Bentonite slurry or additional bentonite chips were then added to 

extend the plug to ground surface. Additional bentonite grout or chips were periodically added 

to the annular space as the grout settled below ground surface. Pea gravel was then placed at 
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ground surface around the PVC riser and over the grout. A locking well cap was installed on the 

PVC riser; a copy of the accompanying key is located at the WRST headquarters. 

All downhole drilling equipment was decontaminated on-site using a pressure washer 

after each boring was completed. Each well was developed within one week of installation using 

a downhole submersible pump. Development was typically initialized at a high discharge rate 

with periodic surging actions, followed by more consistent pumping at a lower rate until 

discharge water was observed to be clear. However, if the formation permeability was too low to 

allow a high discharge rate (e.g., MW-J3), the well was developed at a lower rate. 

5.3.2 SAMPLING AND ANALYTICAL PROCEDURES: WATER LEVEL 

MONITORING 

A survey was performed by Phillips Surveying on August 25, 2009. Phillips Surveying 

surveyed the top of casing elevations of all new monitoring wells and the ground surface of all 

soil borings using a level and a rod for elevation and a sub-meter GPS for location. The 

elevation datum was derived using the National Oceanic and Atmospheric (NOAA) GPS online 

positioning user status process. For ease of interpretation between groundwater elevations and 

ground contours, the surveyed ground elevations were adjusted to match the contour map 

provided by NPS (there was a consistent difference between the surveyed elevations and the 

mapped contours of approximately 25 feet). On August 26, 2009 and August 30, 2009, the depth 

to groundwater in all eight monitoring wells was gauged using an electronic water-level tape. 

5.3.3 SAMPLING AND ANALYTICAL PROCEDURES: MONITORING WELL 

SAMPLING 

On August 22, August 26, August 27, and August 29, 2009, the seven wells that 

contained water (MW-J1, MW-J2, MW-J3, MW-J4-D, MW-J4-S, MW-J5, and MW-J8) were 

sampled using slow purge sampling techniques, except at MW-J1 where low flow rate could not 

be achieved. However, parameters were monitored and sampling occurred at MW-J1 after 

parameter stabilization. Monitoring well MW-J7 and the previously installed monitoring well 

MW-3 did not contain enough water to develop or sample; MW-3 appeared to be obstructed by 

ice beginning 10 feet below the top of casing and the boring at MW-J7 did not cross the water 

table before encountering dry bedrock. Sampling was conducted on the following days. 
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 August 22: MW-J2 was initially sampled immediately after development because it was 

uncertain whether the water column would freeze after rising into the 30-foot layer of 

permafrost. 

 August 26: MW-J1, MW-J8, and MW-J5 

 August 27: MW-J4D was sampled and MW-J2 was re-sampled because the water 

column had not frozen and a longer time period between drilling and development was 

preferred (both MW-J2 samples were analyzed). 

 August 29: MW-J4S and MW-J3 

At each well, purge water was monitored for temperature, pH, oxidation-reduction 

potential (ORP), dissolved oxygen, and specific conductance using a YSI multi-parameter 

instrument equipped with an enclosed flow-through cell. Turbidity was analyzed using a HACH 

2100P turbidimeter. Groundwater samples were collected after these parameters stabilized with 

less than 10 percent change between sequential readings recorded over a period of at least ten 

minutes. 

All groundwater samples were placed in coolers that were sent via two-day delivery 

under chain of custody protocol to TestAmerica for analysis. Groundwater samples were 

analyzed for the following constituents: arsenic, barium, cadmium, chromium, copper, iron, 

lead, nickel, selenium, silver, vanadium, and zinc by EPA Method 6020, and mercury by EPA 

Method 7470A. The samples were preserved with nitric acid during collection. As planned, the 

samples were not chilled when collected or shipped because this step was technically 

impracticable and would not appreciably affect the quality of the samples since the preserved 

metals would not degrade or volatilize under typical ambient temperatures. 

Water necessary for decontamination, grout mixing, and drilling at MW-J2 only, was 

pumped from Skookum Creek near its crossing with the Nabesna Road and placed in 

polyethylene tanks for transport to the Site. Two samples were collected from these 

polyethylene tanks (WT-1 and WT-2) on August 17, 2009 analyzed for the same list of metals as 
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for groundwater samples. In addition, surface water sample SW-J10 was collected on August 

15, 2009 from Skookum Creek at the approximate location of water withdrawal. 

5.4 RESULTS: GROUNDWATER INVESTIGATION 

5.4.1 RESULTS: HYDRAULIC GRADIENTS AND GROUNDWATER FLOW 

DIRECTION 

Groundwater elevations calculated from water-level data collected on August 26, 2009, 

and August 30, 2009 are provided in Table 6. A map of the August 30, 2009 data (the set of data 

collected after all development and sampling) is provided in Figure 14 

The Site and regional area topographic slope direction to the northeast and the flow 

direction of the local creeks and regional rivers provide sufficient information to estimate a 

groundwater gradient direction to the northeast (shown in Figure 14). The water-level data 

collected from the monitoring wells show a similar pattern; however, a consistent northeast 

gradient could not be mapped between all monitoring wells. Significantly lower water levels 

were measured at locations MW-J1 and MW-J2 relative to monitoring wells installed within the 

tailings area, resulting in apparent gradient directions to the north and east relative to higher 

water levels in the center of the Lower Tailings at MW-J5, MW-J4, MW-J3, and near the Upper 

Tailings at MW-J8. These higher water levels could be influenced by perched groundwater or 

permafrost, while the relatively lower water levels at MW-J1 and MW-J2 may reflect the actual 

water table within the upgradient limestone bedrock. Regardless, the water-level elevations 

between upgradient and downgradient wells do not follow an entirely consistent and predictable 

pattern, which may indicate the wells are monitoring significantly different hydrogeologic units 

(e.g., an upper perched aquifer versus a water table aquifer from the upgradient limestone 

bedrock). 

Vertical hydraulic gradient directions could be determined at the only well couplet, MWJ4-S and MW-J4-D. In this well couplet, groundwater gradient was upward between the lower 

and upper aquifers as evidenced by a higher potentiometric head in the deep well than in the 

shallow well. This gradient indicates that dissolved contaminants, if present, would be less 

likely to migrate downward in this area. 
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5.4.2 RESULTS: GROUNDWATER ANALYSIS 

All metals sampling results for the monitoring wells are presented in Table 7. No metal 

concentrations exceeded the ADEC groundwater screening levels. The only couplet of wells at 

the Site, MW-J4-S and MW-J4-D, shows increased concentrations of arsenic, copper, iron, 

nickel, vanadium, and zinc with increased depth, and decreased concentration of lead with 

increased depth. 

6. SURFACE WATER AND SEDIMENT ASSESSMENT 

6.1 PURPOSE AND GENERAL APPROACH: SURFACE WATER AND SEDIMENT 

ASSESSMENT 

The impact of mine tailings on surface water at the Site has been investigated previously 

by URS (1995), USGS (1999), and NPS (2004), during both the wet season and the dry season. 

Sample results indicated that, under some conditions, surface water at the Site is impacted by 

aluminum, cadmium, copper, iron, and zinc. However, relatively little background surface water 

quality data is available. Since the studies conducted by URS (1995) and USGS (1999), ditches 

around the tailings have been rehabilitated and constructed in an effort to divert surface water 

flow away from the tailings. Sampling conducted during the SSI was intended to increase the 

body of data documenting background surface water quality, and evaluate the impact of the 

ditching on surface water quality. Although August had been identified as a wet season, little 

rainfall during the three weeks of investigation, coupled with reportedly no rain in June and July, 

effectively resulted in these samples being considered “dry season” samples. 

In addition, the reported locations of stream channels have varied between the previous 

investigations conducted at the Site, highlighting the dynamic nature of surface water flow at the 

Site. The stream channels of Cabin Creek were mapped during this investigation in order to 

determine how current flow patterns compare to those documented in the past. 

6.2 LOCATIONS: SURFACE WATER AND SEDIMENT ASSESSMENT 

Twenty-six locations for surface water sampling were proposed in the Field Sampling 

Plan, based on the review of Site maps, aerial photographs, and documentation of previous 

surface water sampling conducted at the Site. Because the investigation was performed during a 

relatively dry period, the streams were dry at some of the locations chosen for sampling. Of the 
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was analyzed using a HACH 2100P turbidimeter. Field duplicates were collected at three 

sample locations by filling a second bottle from the same filter vessel. At two locations, an 

additional 500 mL of sample was sent to the lab to permit a matrix spike/matrix spike duplicate 

analysis. Following the completion of surface water sampling, an equipment blank was collected 

by filling the filter vessel with distilled water and pumping it through a disposable filter into a 

sample container. 

6.3.3 SAMPLING AND ANALYTICAL PROCEDURES: SEDIMENT SAMPLING 

At each surface water sampling location, a sediment sample was collected by scooping a 

volume of approximately 200 mL of sample into a plastic bag. Following completion of the 

sediment sampling, the bagged samples were brought to the field laboratory for XRF metals 

screening analysis. All samples were processed according to the procedures for soil samples 

detailed in Section 4.3 to obtain the most accurate results possible. 

After screening the 23 processed samples with the XRF, 6 processed samples were 

submitted to the laboratory for confirmation analysis. Confirmation samples were selected to 

include three upstream and three downstream samples, with five samples having high screening 

concentrations and one sample having low screening concentrations. 

An equipment blank was collected after the completion of sediment sampling by pouring 

distilled water over the sampling trowel into a sample container. 

6.4 RESULTS: SURFACE WATER AND SEDIMENT ASSESSMENT 

6.4.1 RESULTS: STREAM CHANNEL MAPPING 

Stream channels mapped during the SSI are plotted on Figure 15. Mapping of the stream 

channels revealed a complex flow pattern that likely has strong seasonal and long-term 

variability. The upper reach of Cabin Creek, from SW-J2 to SW-J7, is a rocky channel with an 

approximate width of 50 to 100 feet; the channel bed contained rocks up to several feet in 

diameter. Flow in the channel occupied only a narrow portion (2 to 5 feet) of the total channel 

width, and in much of the upper reach no surface water flow was observed: on August 9, 2009, 

water was observed to be flowing from SW-J2 (the farthest upstream extent of mapping) until a 

point approximately 1,800 feet downstream, where the flow migrated below the ground surface. 
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A small portion of this flow re-emerged at a point approximately 1,300 feet further downstream 

and flowed for approximately 200 feet prior to submerging again. No flow was observed on this 

date between this point and SW-J7. Several showers occurred between this date and August 15, 

2009, when this reach of the creek was revisited. On August 15, continuous flow between SWJ2 and SW-J7 was observed. 

No water was observed between SW-J7 and a point approximately 300 feet south of the 

eastern edge of the Lower Tailings, where water from nearby seeps flows into the Cabin Creek 

channel. Below SW-J7, the Cabin Creek streambed becomes more vegetated; it appeared that 

during periods of flow water would disperse into numerous smaller channels up to approximately 

3 feet wide. 

Between the eastern end of the Lower Tailings and sample location SW-J29 

(approximately 1 mile to the east) is a large and relatively flat area with numerous seeps. Many 

stream channels were observed in this area, several of which emerged from seeps and extended 

for only a few hundred feet before infiltrating into the ground. As reported by the USGS (1999), 

three relatively well-established channels are present in this area, indicated on Figure 15 as the 

Main Branch, North Branch, and South Branch of Cabin Creek. In these three channels, 

continuous surface flow was observed only in the Main Branch. Vegetative growth patterns 

suggest that the layout of these channels may change during large events. For example, dry 

channels were observed with characteristic streambank vegetation such as willows and alders, 

but more recently developed flow channels without this type of vegetation were also present. 

Because the topography in this area is relatively flat, disturbances such as all-terrain vehicle use 

can result in the diversion of flow from established channels. 

The North Branch of Cabin Creek was observed to begin at a series of seeps a short 

distance (approximately 50 feet) north of the Main Branch near SW-J30. The channel remained 

distinct until entering a wetland area with several interconnected ponds approximately 500 feet 

downstream of SW-J19. At the eastern edge of this wetland area, a distinct channel was mapped 
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from the base of a beaver dam to its confluence with the Main Branch of Cabin Creek near SWJ21. 

The South Branch of Cabin Creek was more poorly defined than the North Branch or the 

Main Branch. The channel appeared to originate about 500 feet south of the Main Branch, where 

several seeps were observed to discharge into a well-defined channel with banks approximately 

10 feet high. Water flowed through this channel until spreading out into a wetland 

approximately 1,000 feet downstream of SW-J18. This wetland appeared to discharge into a 

small channel (approximately 1 foot wide) that joined the Main Branch of Cabin Creek near SWJ29. 

Below SW-J29, Cabin Creek enters a V-shaped valley that allows for little horizontal 

migration of the stream channel. Flow was observed to increase significantly after SW-J22, 

below the confluence with a large tributary reported to drain the Rambler Mine area (USGS, 

1999). Below this confluence, the grain size of stream sediments is markedly larger than 

upstream, and it is likely that the higher flow rates in this portion of the channel would largely 

prevent deposition of fine-grained tailings that may be transported by Cabin Creek. 

6.4.2 RESULTS: SURFACE WATER AND SEEP SAMPLING 

The field-measured parameters for surface water are summarized in Table 8. In general, 

the pH of Cabin Creek was found to be slightly basic, especially in the samples collected from 

the concentrated channel downstream of SW-J22. Measurements of pH collected during the SSI 

showed no discernable impact to Cabin Creek by acidic runoff during the SSI. Specific 

conductance was higher in surface water samples collected from below the tailings than in 

samples collected above the tailings. 

Complete analytical results of the surface water sampling are provided in Table 8. 

Exceedences of screening levels are summarized on Figure 16. Background samples collected at 

eight locations indicate a range of surface water quality. The highest concentrations of targeted 

metals were found at springs located above the mill buildings (locations SW-J6 and SW-J31). 

SW-J6, which had been sampled previously by the USGS, contained high concentrations of all 
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metals, except vanadium, relative to other background samples. Aluminum was detected in this 

sample at 229 ug/L, above the ADEC screening level of 87 ug/L. Metals concentrations in SWJ31 were also high relative to other background samples, but no screening levels were exceeded. 

The surface water from each of these seeps traveled overland for a short distance in the direction 

of Cabin Creek before submerging below ground, so no direct connection between the seeps and 

Cabin Creek was observed during the SSI. 

Metal concentrations in the background Cabin Creek samples (SW-J2, SW-J3, and SWJ7) were generally low. Higher concentrations of metals were observed in background samples 

collected from other streams, suggesting that the surficial geology at each area has an effect on 

the water quality. These samples from intermediate reaches of other streams may be most 

representative of a background concentration in the intermediate reaches of Cabin Creek. 

Results of downstream sampling indicated a minimal impact to surface water quality, 

constrained to approximately 500 feet downstream of the tailings, with the exception of iron, 

which was elevated at locations up to 0.3 mile below the eastern edge of the Lower Tailings. 

Cadmium was found to exceed ADEC screening levels in the three samples closest to the Lower 

Tailings (SW-J32, SW-J13, and SW-J14). Cadmium was also detected in SW-J20, an additional 

1,900 feet downstream of SW-J14, but at a concentration below its ADEC screening level. Iron 

was found to exceed screening levels at three locations downstream of the tailings: SW-J19, SWJ30, and SW-J28. Stream sediments in these three locations were observed to have a rust-orange 

color, indicating the likely presence of iron bacteria. Concentrations of iron in these samples 

ranged from 1,150 ug/L to 1,970 ug/L, comparable to the iron concentrations observed in 

groundwater. 

6.4.3 RESULTS: SEDIMENT SAMPLING 

Complete laboratory and XRF screening results of the sediment sampling are provided in 

Table 9. Exceedences of sediment screening levels are summarized on Figure 17. Samples 

collected from Cabin Creek upstream of the mill building (SE-J2, SE-J3, and SE-J7) contained 

generally low metals concentrations, with no exceedances of sediment screening levels for the 

list of targeted analytes. Concentrations of copper determined by the XRF were only slightly 
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below screening levels in SE-J3, and exceeded screening levels in SE-J2 (although the laboratory 

result was less than the screening level). 

Sediment samples from background locations in other streams contained generally low 

metals concentrations, comparable to those reported in the Cabin Creek background samples. 

Like those samples, copper concentrations determined by XRF analysis were just below the 

screening level. Additionally, the arsenic concentration in SE-J23 from a creek reported to drain 

the Rambler Mine Area (USGS, 1999) was 16 mg/kg, in excess of the screening level. 

Elevated concentrations of several targeted metals were found in sediment samples 

collected below two springs above the mill building (SE-J6 and SE-J31). Sample SE-J6 

contained arsenic, cadmium, copper, nickel, and zinc at concentrations significantly above 

sediment screening levels; the concentration of copper exceeded the screening level by a factor 

of nineteen. Concentrations of arsenic in samples SE-J6 and SE-J31 exceeded the screening 

level of 5.9 mg/kg, with 33.9 mg/kg in SE-J36 and 46.2 mg/kg in SE-J31. Although these 

samples were collected beneath flowing water, they do not likely represent material transported 

by surface flow, and may be considered more representative of background soils than 

background sediments. 

Downstream of the tailings, lead was detected above its screening level of 35 mg/kg in 

the three sediment samples closest to the tailings (SE-J32, SE-J13, and SE-J14). Among these 

samples, the highest laboratory-measured lead concentration was 114 mg/kg in SE-J32. 

Cadmium was detected above its screening level in the two sediment samples collected closest to 

the tailings (SE-J32 and SE-J13). No cadmium was detected in sediments downstream of this 

point; however, the high detection limits achieved with the XRF inhibited the ability to screen 

for this metal at concentrations near the screening level. 

Arsenic was detected above its screening level of 5.9 mg/kg in all Cabin Creek samples 

downstream of the tailings, with the exceptions of SE-J20 and SE-J30, located in the Main 

Branch of the creek. In general, arsenic concentrations decreased with greater distance 
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downstream; however, the samples with the most elevated concentrations of arsenic (SE-J19 and 

SE-J29) were on the spring-fed North Branch and South Branch of Cabin Creek, approximately 

0.3 mile and 1.5 miles, respectively, from the tailings. 

Zinc was detected above its screening level of 123 mg/kg in five locations, including the 

three locations closest to the tailings (SE-J32, SE-J13, and SE-J14). The most elevated 

concentration of zinc was from SE-J6, located above the mill building; however, as discussed 

above, this sample may not be representative of background sediments. In laboratory-analyzed 

samples where zinc exceeded the screening level, concentrations were relatively close to the 

screening level (156 mg/kg and 145 mg/kg in SE-J13 and SE-J32, respectively). The zinc 

concentration determined by the XRF in SE-J14 was more elevated, at 394 mg/kg. This may 

reflect the generally high bias of the XRF relative to the laboratory. 

Sediment samples collected from SE-J22 and SE-J23 did not exhibit elevated 

concentrations of lead or arsenic. However, the stream bank in the vicinity of these two 

locations appeared to be composed of mill tailings, and a sample of this bank (BANK) analyzed 

with the XRF showed concentrations reflective of tailings (approximately 2,000 mg/kg arsenic 

and 2,700 mg/kg in duplicate samples), as discussed in Section. In addition, a sample collected 

in the middle portion of the South Branch by the USGS was reported to have an appearance and 

composition characteristic of tailings (USGS, 1999), but this deposit was not observed during the 

SSI. 

Metals concentrations were not elevated in the samples from SE-J24, taken at the mouth 

of Cabin Creek, or SE-J26, collected from a point just downstream from its confluence with Jack 

Creek. 

7. ANALYSIS: NATURE AND EXTENT OF CONTAMINATION 

7.1 ANALYSIS: BACKGROUND SOIL CONCENTRATIONS 

Results of the background soil sampling indicate naturally-occurring elevated 

concentrations of arsenic in soils collected above the mill building and cross-gradient of the 

tailings. In these soils, arsenic concentrations ranged from 24.7 to 130 mg/kg. The arsenic 
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concentration was found to be low (1.3 mg/kg) in the alluvium south of the Upper Tailings. 

Because the soils beneath the tailings represent the contributions of talus and alluvium, this range 

of background concentrations is representative of the range that would be expected to be 

mutually-occurring beneath the tailings. 

7.2 ANALYSIS: BACKGROUND SURFACE WATER CONCENTRATIONS 

Although August is considered to be relatively wet, based on the low rainfall amounts in 

the summer of 2009, the sampling appears to have occurred during a dry season. Results of 

background surface water sampling showed no targeted metals to be present above ADEC 

screening levels at the six stream locations tested. More elevated concentrations of some metals 

were detected in samples from SW-J6 (the aluminum concentration was particularly high in this 

sample) and SW-J31, located at seeps above the mill building. These seep samples may or may 

not be representative of surface water quality upgradient of the Site, but they do indicate the 

potential of naturally-occurring metals in groundwater to impact surface water in areas of 

widespread groundwater discharge, such as the area below the Lower Tailings. It is possible that 

these seeps include water from mine shafts or mineralized fractures in the upgradient bedrock. 

7.3 ANALYSIS: BACKGROUND SEDIMENT CONCENTRATIONS 

Results of sediment sampling upstream of the mill building indicate generally low metals 

concentrations, with no exceedances of sediment screening levels for the targeted metals. 

Copper concentrations were elevated and were only slightly below the screening levels. Metals 

concentrations were comparable in the three samples collected from other streams, although 

arsenic was found to exceed the screening level in SE-J23, collected from a tributary to Cabin 

Creek. Results from SE-J6 and SE-J31, which were collected from sediment beneath spring 

discharges above the mill, should be disregarded as potential background concentrations because 

they are likely to be more representative of surface soils than sediments. It is unlikely that the 

soil beneath these springs is used by any receptors that would typically live in freshwater 

sediments. 

7.4 ANALYSIS: EXTENT OF TAILINGS AND IMPACTED SOIL 

The visible extent of the continuous tailings deposits have changed little since the most 

recent delineation by NPS in the late 1990s. Chemical data collected during this SSI indicate 
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that tailings have migrated to or were initially deposited over an area that is substantially larger 

than is visible but has since become vegetated. In addition, chemical data confirm that tailings 

have migrated east of the visible end of the Lower Tailings, likely as a result of transport by 

surface water over continually changing depressions caused by animal and ATV use. 

Among the background samples collected in this SSI, the SS-J5 sample was judged most 

representative of the soils at the Site. The arsenic concentration from this sample (estimated at 

130 mg/kg) and the ADEC screening level for lead (400 mg/kg), in combination with visual 

observations of orange- or grey-stained soil, were used to differentiate native soil from tailingsimpacted soil. Generally, the extent of tailings-impacted soil north and south of the Upper 

Tailings was bounded by topography immediately beyond visible edge of the tailings to the south 

and by topography immediately beyond the historic drainage ditch to the north. Conversely, 

local topography appears to have controlled northerly migration of the Lower Tailings, with no 

evidence of tailings impact found beyond the northern edge of the visible tailings. South of the 

visible Lower Tailings, tailings and impacted soil extended in some cases to the recently 

rehabilitated Southern Historic Ditch, up to approximately 200 feet south of the visible edge of 

the tailings. Easterly migration of the Lower Tailings appears to be confined to long, narrow 

fingers that follow small depressions such as those left by game trails. These fingers were found 

to extend up to 200 feet beyond the main body of the Lower Tailings, beyond which point no 

visible tailings were observed. 

In addition, limited sampling conducted between the Upper and Lower Tailings indicates 

that tailings or soil significantly impacted by tailings may extend continuously between the two 

bodies of tailings, mixed in or covered by disturbed soil. 

Sampling conducted in soil borings advanced beneath the tailings indicated that only 

lead, arsenic, and copper are found in soil at concentrations exceeding ADEC screening levels 

(copper exceeded ADEC standards in 1 of 55 samples analyzed). Lead exceeded screening 

levels in only three samples, and concentration profiles with depth do not indicate leaching of 

lead from the tailings (i.e., concentration was not observed to decrease with depth). However, 
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arsenic appears to have leached beneath the tailings to varying depths beneath each deposit. The 

average depth of arsenic impacted soil was estimated at 0.8 feet beneath the bottom of the Upper 

Tailings and 1.2 feet beneath the bottom of the Lower Tailings. 

7.5 ANALYSIS: IMPACTS TO GROUNDWATER 

None of the groundwater samples contained concentrations of any analyzed metals that 

exceeded ADEC screening levels, and there do not appear to be any discernable impacts to 

groundwater from the tailings. 

7.6 ANALYSIS: IMPACTS TO SURFACE WATER AND SEDIMENT 

Investigation results showed surface water impacts from the tailings to be minimal, with 

only iron and cadmium detected above ADEC standards in the reaches below the tailings. The 

elevated concentrations of cadmium are indicative of tailings impact, but exceedances of ADEC 

standards were confined to the outflow of seeps located along the Lower Tailings, and the reach 

of Cabin Creek within approximately 1,000 feet of the Lower Tailings. The pH of Cabin Creek 

was slightly basic in all downstream samples, indicating a lack of impacts due to acidic runoff at 

the time of the SSI. 

Impacts to sediments from the tailings appear to be confined to approximately 1,000 feet 

downstream of the Lower Tailings, based on elevated concentrations of arsenic, copper, lead, 

and zinc. Although arsenic and copper concentrations continued to be elevated in multiple 

samples collected from all branches of Cabin Creek until its confluence with Jack Creek, there is 

no discernable trend of decreasing concentrations with distance and, given the generally high 

arsenic concentrations in surrounding soils, there is insufficient evidence that would implicate 

the tailings as the sole source of elevated arsenic. It is notable, however, that isolated deposits of 

tailings have been observed on the streambanks well downstream of the tailings, including one 

deposit that was observed and sampled in 2009 (“Bank”; no other deposits were observed in 

2009, although others have been noted previously). 
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8. CHARACTERIZATION TO SUPPORT POTENTIAL RESPONSE ACTIONS 

8.1 GEOTECHNICAL SAMPLING 

8.1.1 PURPOSE AND GENERAL APPROACH: GEOTECHNICAL SAMPLING 

Previous to the Johnson Company SSI, the soils on the eastern part of the Upper Tailings 

had been characterized by three soil borings completed in 1998 (B-1, located on the southern 

side of the Southern Historic Ditch near the approximate middle of the Upper Tailings; and MW2 and 4, shown on Figure 13). This general area was preliminarily identified as a potential 

location for on-site consolidation, which could be among the array of potential alternatives 

considered in the EE/CA Report. To determine design parameters for such a consolidated 

tailings pile, the characterization of the soils beneath the potential tailings consolidation area was 

refined with additional soil borings through the Upper Tailings. At some of these locations, 

undisturbed samples were collected to determine the compressive and shear strength of the 

cohesive silt. Tailings samples were also collected and analyzed for geotechnical parameters that 

could dictate the height and sidewall slopes of a consolidated pile. 

8.1.2 LOCATIONS: GEOTECHNICAL SAMPLES 

Locations of the ten soil borings used for geotechnical sampling are shown in Figure 18. 

These geotechnical borings were situated on the Upper Tailings, with SB-J4, J5, J12, and J15 

dispersed across the western portion of the Upper Tailings, and SB-J10, J11, J13, J14, J16, and 

J17 more closely concentrated in the eastern portion, which appeared to be a more suitable 

consolidation area based on the gentler ground slope. Undisturbed samples of cohesive soils 

were collected from SB-J6 (2 to 4 feet), SB-J10 (1 to 3 feet), SB-J15 (0 to 3 feet), and SB-J16 (2 

to 4 feet). Locations of the 20 surficial tailings samples (Tail-MW-J3 and J4, Tail-SB-J2 through 

J17, and Tail-19 and 20) are shown on Figure 19. Surficial tailings samples were collected from 

both the Upper and Lower Tailings in order to assess if and how the properties vary. 

8.1.3 METHODS: GEOTECHNICAL SOIL BORINGS 

All soil borings were drilled using a track-mounted hollow stem auger rig. The hollow 

stem auger method operated by rotating a 4.25 inch inside diameter/8 inch outside diameter 

spiral drilling rod (the hollow stem auger) attached to a pilot auger bit. Soil cuttings generated 

during drilling were brought to the surface via the auger flights and shoveled into drums. A 2-

foot long, 3-inch diameter split-spoon sampler was placed inside the hollow center of 
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the augers and hammered into the soil with a hydraulic 30-inch-drop, 340 pound 

hammer. The number of hammer blows required to drive the split spoon every 6-inch interval 

was recorded on the field boring logs. 

8.1.4 SAMPLING AND ANALYTICAL PROCEDURES: GEOTECHNICAL SOIL 

SAMPLING 

Disturbed soil samples were collected continuously by driving the 2-foot split spoon from 

ground surface to a maximum depth of 20 feet below ground surface. Soils retrieved in the 

split spoon samplers were logged and then retained in Ziploc bags, with a separate bag 

for each type of soil identified in each spoon. Following review of the boring logs, samples 

of selected soils were submitted for grain size analysis (ASTM D422 with hydrometer analysis to 

determine the percentage of fine materials). Between two and four samples were collected per 

boring, creating a total of 29 grain size samples. 

Co-located borings were drilled at four locations (adjacent to SB-J6, J10, J15, and J16) 

and 3-inch diameter, 3-foot long Shelby tubes were used to collect undisturbed samples of the 

shallow silt layer between 0 and 4 feet below ground surface. The Shelby tubes were capped on 

both ends and remained upright during transport to the laboratory. Undisturbed samples were 

analyzed for grain size by ASTM Method D422, uniaxial compression via ASTM Method 

D2435, and specific gravity using ASTM Method D854. Permeability testing was not requested 

because the samples were dry. All geotechnical soil samples were delivered on August 31, 2009, 

by The Johnson Company to DOWL HKM Alaska Testlab of Anchorage, Alaska, for analysis. 

8.1.5 SAMPLING AND ANALYTICAL PROCEDURES: TAILINGS SAMPLES 

FOR GEOTECHNICAL ANALYSIS 

On August 20, 2009, a total of 20 tailings samples were collected from 0 to 1.5 feet bgs 

and placed in dedicated 5-gallon buckets. Denali Drilling transported the samples to DOWL 

HKM Alaska Testlab of Anchorage, Alaska on August 21, 2009. Tailings samples were 

analyzed for grain size according to ASTM D422. Based on the grain size analysis, three 

samples (one tailings sample and two composited soil samples containing a mixture of silt, sand, 

and gravel) were then selected to undergo testing for maximum density using native moisture 

content via a modified 1-Point Proctor test. Sufficient tailings volume was available to perform 

additional analysis on the tailings samples, since a large volume of sample had been submitted 
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for each location. However, the laboratory reported that after performing the grain size testing 

on the soil samples (submitted in smaller volumes because they were collected from the split 

spoons) the silts had been washed out of the samples (the presence of silts was known from 

earlier stratigraphic logging). The decision was made to add a percentage of fines from the 

additional tailings samples to the washed sand and gravel from the soil samples (based on the 

original grain size results) to effectively recreate two representative composited samples. 

8.1.6 RESULTS: GEOTECHNICAL SAMPLING 

The geotechnical sampling results are summarized in Table 5. The grain size analysis of 

the tailings indicated that the composition of the tailings is relatively uniform, with all samples 

characterized as silty sand or sandy silt (Engineering Classification ML). The soil types from the 

soil borings ranged from silty sand to gravel with silt and sand. All soil samples contained at 

least some fraction of silt. In general, the grain size classifications verified the classifications 

made in the field, and the surficial geology is illustrated on the cross sections in Figures 5 

through 8. 

8.2 TAILINGS REPROCESSING SAMPLES 

8.2.1 PURPOSE AND GENERAL APPROACH: TAILINGS REPROCESSING 

SAMPLES 

In order to evaluate the potential for reprocessing the tailings, seven samples were 

collected on August 12, 2009. Samples were analyzed for metals, cyanide bottle roll, acid-base 

accounting, ore characterization, and meteoric water mobility. These analyses provide data 

relevant to the efficacy of processing the tailings at an existing gold extraction mill. 

8.2.2 LOCATIONS: TAILINGS REPROCESSING SAMPLES 

Tailings reprocessing samples were collected by compositing approximately 75 pounds 

of tailings surrounding each of the seven locations (W841 through W847) selected at the Upper 

and Lower Tailings, as shown on Figure 20. 

8.2.3 SAMPLING AND ANALYTICAL PROCEDURES: TAILINGS 

REPROCESSING SAMPLES 

A potential reprocessor conducted all of the sampling and prepared all samples as 

necessary for analysis. The Johnson Company personnel were on-Site during sampling. 

Samples were submitted to ACZ Laboratories for the following analyses: 1) meteoric water 
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mobility tests for 33 metals, which expresses leaching potential under natural weather 

conditions; 2) acid generation potential, which compares the sulfur content of the material, which 

can generate sulfuric acid when the parent minerals are oxidized, with the neutralizing potential 

of other minerals present; and 3) sulfur forms, including pyritic and sulfate. Samples were 

submitted to Alaska Assay Laboratories for the following analyses: 1) metallic screening for 

gold; 2) LECO analysis, which measures the percent carbon and percent sulfur in a sample; and 

3) total metals concentrations for 40 metals. The potential reprocessor conducted the following 

analysis at its laboratory: 1) bottle roll test, which measures the consumption of lime and 

cyanide during recovery of gold from a sample. 

8.2.4 RESULTS: TAILINGS REPROCESSING SAMPLES 

The raw laboratory data is summarized in Table 3. In general, the average gold assay 

values were slightly lower than the values reported in the WGM 1981 study, but the results 

preliminarily indicate that the tailings can be reprocessed and the gold recovered. The tailings 

have a high potential to generate acid runoff, with little buffering capacity. The recovery process 

would require a relatively high amount of lime and cyanide reagents, limiting the number of 

mills for which the Nabesna tailings might be suitable. 

9. FIELD OPERATIONS 

9.1 SITE RECONNAISSANCE, PREPARATION, AND RESTORATION 

PROCEDURES 

Representatives of Denali Drilling and NPS WRST staff walked the Site on June 16, 

2009, to discuss proposed drilling locations and drum storage areas. Alaska Digline was 

contacted regarding buried utilities in the area, and the Site was cleared by the only utility 

service in the area, Copper Valley Telephone, on July 24, 2009. On July 24, 2009, NPS 

requested the services of an archeologist to provide monitoring during all soil-disturbing field 

work to minimize impacts to historical artifacts at the Site, and Northern Land Use Research, 

Inc. (NLUR) was subcontracted for this purpose. Representatives of JCO and NPS walked the 

Site on August 8, 2009, to discuss proposed drilling locations, clearing necessary for drum 

storage and equipment access, and general procedures for operating within the Park. Drilling 

locations and access routes were planned to minimize the disturbance of the tailings, clearing of 

vegetation, and visual impact. These locations and access routes were further refined after a 
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representative of NLUR met with the Cultural Resource Specialist at WRST headquarters on 

August 11, 2009, to discuss specific tasks for the Site. A letter report prepared by NLUR 

documenting their observations during the investigation is included as Attachment 3. No 

significant disturbances to historical artifacts resulted from the SSI activities. 

Following completion of the field work, an effort was made to return each work area or 

sampling location to its original condition. With the exception of flagging used to indicate 

surface water monitoring points and multi-increment sample locations, all flagging was removed 

from the Site prior to demobilization. All garbage was removed from the Site, and all drums 

containing waste soils were moved to the designated drum storage area. Drums containing purge 

water and decontamination water were left in-place pending analytical results to determine 

disposal. Following receipt of the analytical results, which showed that the water contained in 

the drums had only naturally-occurring concentrations of metals and was well below regulatory 

standards, the water was slowly discharged to the ground surface (away from the tailings) before 

ambient temperatures fell below freezing to avoid any uncontrolled releases that could occur if 

the drums froze. 

9.2 BOREHOLE ABANDONMENT 

All boreholes intended for geophysical or environmental sampling (i.e. sampling 

locations with prefixes SB) were abandoned in place by one of two methods. Boreholes SB-J4, 

SB-J5, SB-J6, SB-J7, SB-J10, and SB-J12 were filled from bottom to top using a tremie pipe and 

grout pump containing a bentonite slurry composed of bentonite powder and drilling water from 

Skookum Creek. If settling of grout occurred, sufficient amounts of bentonite chips and drilling 

water were added to fill the hole to ground surface. Boreholes SB-J2, SB-J8, SB-J9, SB-J11, and 

SB-J13 through SB-J17 were filled with bentonite chips hydrated in-situ with drilling water. 

Additionally, borehole MW-J6, which was intended as a monitoring well location, was 

abandoned after drilling to bedrock without encountering groundwater. MW-J6 was abandoned 

in place by filling it from bottom to top with a bentonite slurry via a tremie pipe grout pump. 
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9.3 SURVEYING 

The location of all monitoring wells was determined by a certified land surveyor, Phillips 

Surveying, and provided in reference to the Alaska State Plane system. The elevations of all 

monitoring wells at the water level measuring point were included in the survey, as were the 

ground surface elevations of all soil boring locations. The elevation datum was derived using the 

National Oceanic and Atmospheric (NOAA) GPS online positioning user status process. For 

ease of interpretation between groundwater elevations and ground contours, the surveyed ground 

elevations were adjusted to match the contour map provided by NPS (there was a consistent 

difference between the surveyed elevations and the mapped contours of approximately 25 feet). 

A GPS survey was conducted by The Johnson Company of all of surface water, sediment, 

background soil, and tailings delineation sampling locations using a GPS with submeter 

accuracy. All observed channels of Cabin Creek within approximately 1.5 miles of the tailings 

were mapped using a handheld GPS accurate to approximately 10-20 feet. 

9.4 EQUIPMENT DECONTAMINATION 

All equipment that directly or indirectly contacted samples was decontaminated before 

and after use with a pressure washer or, in the case of the auger flights, with a wire brush and 

water. Equipment included casing, drill bits, auger flights, split spoons, and instruments. 

Dedicated tubing was used in each well. For sampling and smaller drilling devices, a mixture of 

potable water and Alconox was used to wash the equipment, followed by a rinse with deionized 

water. 

9.5 FIELD WORK DOCUMENTATION 

Standardized sampling forms were used whenever possible to document sampler 

installations, soil logging, and sample collection. A daily log was completed each day that work 

occurred at the Site. These logs are provided in Attachment 5. 

10. QUALITY CONTROL 

10.1 QUALITY CONTROL FOR FIELD SCREENED SAMPLES 

This section presents an evaluation of quality control (QC) procedures applied to the 

analysis of soil and groundwater samples collected during the August 2009 SSI field program. 

The data quality review was performed using the Data Quality Objectives (DQOs) outlined in the 
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QAPP and the U.S Environmental Protection Agency (EPA) Contract Laboratory Program 

National Functional Guidelines for Inorganic Data Review (October, 2004) for guidance. The 

results of the QC review are summarized below and in the referenced tables. 

10.1.1 PROCESSED AND UNPROCESSED IN-SITU SCREENING SAMPLES 

Soil samples for XRF screening collected between August 12 and 28, 2009, were 

homogenized, dried, pulverized, and sieved in a field laboratory before being analyzed using the 

XRF. As described in Section 4.3, the processing step had the potential to prevent the full 

delineation of the tailings extents, and a field study was performed to determine the difference 

between analytical results for unprocessed in-situ soil samples and soil samples that were 

processed at the field laboratory. Thirteen samples from the Upper Tailings and 10 samples from 

the Lower Tailings were included in the field study conducted concurrently with the delineation 

activities. Concentrations of both lead and arsenic in processed XRF samples exceeded the 

results in the in-situ XRF samples by a median factor of 1.5. This difference was judged 

acceptable given Site conditions. 

10.1.2 LABORATORY CONFIRMATION OF SCREENING SAMPLES 

The accuracy of XRF results is evaluated by comparing results of laboratory and 

processed XRF samples. The RPD between laboratory results and processed XRF screening 

results for the surficial soil samples are summarized in Tables 1a and 1b, for subsurface samples 

in Table 4, and for sediment samples in Table 9. Unless noted below, RPDs were either within 

control limits (i.e., below the QAPP upper limit of 50 percent) or not calculated because an 

analyte was not detected above the reporting limit in one or both of the samples compared. 

Approximately 5 mL of the homogenized sample was then placed in a disposable plastic 

cup and analyzed with the XRF for 2 minutes. This container was then recombined with the 

sample, and the analysis was repeated with a second 5 mL portion of the homogenized sample. 

Comparison of these two readings of the processed sample allows for verification of the efficacy 

of the homogenization process. In addition, comparison of the processed and in-situ readings 

provides a qualitative assessment of soil heterogeneity. 

Calculated RPDs Exceeding DQOs- Samples from Transects on Upper Tailings (Table 1a): 
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• DS-014- arsenic 136 percent (higher in processed XRF sample), cobalt 192 

percent (higher in processed XRF sample), lead 75 percent (higher in processed 

XRF sample); and 

• DS-016- manganese 50 percent (higher in processed XRF sample) 

RPD comparisons indicate in some samples, arsenic, cobalt, lead, and manganese may be 

reported at higher concentrations in processed XRF screening samples than in laboratory 

samples, but no consistent trend was present for any of the analytes. 

Calculated RPDs Exceeding DQOs- Samples from Transects on Lower Tailings (Table 1b): 

• DS-139- copper 60 percent (higher in processed XRF sample), iron 96 percent 

(higher in processed XRF sample), manganese 89 percent (higher in processed 

XRF sample), and vanadium 67 percent (higher in processed XRF sample); 

• DS-150- cobalt 189 percent (higher in processed XRF sample), iron 75 percent 

(higher in processed XRF sample), lead 110 percent (higher in laboratory 

sample), manganese 81 percent (higher in laboratory sample), zinc 108 percent 

(higher in laboratory sample); 

• DS-167- cobalt 169 percent (higher in processed XRF sample), iron 73 percent 

(higher in processed XRF sample); 

• DS-177- iron 72 percent (higher in processed XRF sample), manganese 77 

percent (higher in processed XRF sample), mercury 195 percent (higher in 

processed XRF sample), silver 168 percent (higher in processed XRF sample); 

• DS-190- iron 61 percent (higher in processed XRF sample), mercury 196 percent 

(higher in processed XRF sample); 

• DS-201- chromium 177 percent (higher in processed XRF sample), iron 97 

percent (higher in processed XRF sample), manganese 79 percent (higher in 

processed XRF sample), mercury 196 percent (higher in processed XRF sample), 

zinc 68 percent (higher in processed XRF sample); 

• DS-218- iron 77 percent (higher in processed XRF sample); 
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• DS-220- chromium 180 percent (higher in processed XRF sample), iron 101 

percent (higher in processed XRF sample), manganese 78 percent (higher in 

processed XRF sample ), zinc 72 percent (higher in processed XRF sample); and 

• DS-227- copper 66 percent (higher in processed XRF sample), iron 89 percent 

(higher in processed XRF sample), manganese 104 percent (higher in processed 

XRF sample). 

As with the Upper Tailings, the XRF processed results were consistently higher than the 

laboratory results in cases where the RPD exceeded 50 percent. The reported XRF screening 

concentrations of cobalt, copper, iron, manganese, and zinc are considered to be biased high and 

have been flagged with a “J+” in Table 1b. 

Calculated RPDs Exceeding DQOs: Samples from Soil Borings (Table 4): 

• MW-J3 (2.6-3.0 feet)- manganese 117 percent (higher in processed XRF sample); 

• SB-J2 (6.3-6.9 feet)- iron 93 percent (higher in processed XRF sample), manganese 101 

percent (higher in processed XRF sample); 

• SB-J6 (3.1-3.4 feet)- chromium 130 percent (higher in processed XRF sample), iron 60 

percent (higher in processed XRF sample), manganese 78 percent (higher in processed 

XRF sample); 

• SB-J8 (7.3-8.0 feet)- chromium 126 percent (higher in processed XRF sample), iron 65 

percent (higher in processed XRF sample); 

• SB-J12 (2.7-3.2 feet)- iron 57 percent (higher in processed XRF sample); and 

• SB-J17 (2.1-2.8 feet)- iron 81 percent (higher in laboratory sample), manganese 119 

percent (higher in processed XRF sample), zinc 81 percent (higher in processed XRF 

sample). 

In soil boring samples (all processed before XRF screening), manganese and iron appear 

to be biased high in the XRF screening compared to laboratory data. Detected concentrations 

with calculated RPDs that exceeded control limits have been flagged with a “J+” in Table 4, 
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indicating that the XRF screening result is an estimated quantity, but the result may be biased 

high. 

Calculated RPDs Exceeding DQOs: Samples from Sediments (Table 9): 

• SE-J2- copper 111 percent (higher in processed XRF sample), iron 151 percent (higher in 

laboratory sample),manganese 144 percent (higher in processed XRF sample); 

• SE-J6- arsenic 66 percent (higher in processed XRF sample), chromium 159 percent 

(higher in processed XRF sample), iron 93 percent (higher in processed XRF sample), 

manganese 53 percent (higher in processed XRF sample); 

• SE-J31- arsenic 55 percent (higher in processed XRF sample), iron 102 percent (higher in 

processed XRF sample), manganese 60 percent (higher in processed XRF sample), zinc 

64 percent (higher in processed XRF sample); 

• SE-J13- iron 103 percent (higher in processed XRF sample), manganese 92 percent 

(higher in processed XRF sample); 

• SE-J32- arsenic 64 percent (higher in processed XRF sample), iron 110 percent (higher in 

processed XRF sample), manganese 105 percent (higher in processed XRF sample; and 

• SE-J18- arsenic 69 percent (higher in processed XRF sample), iron 98 percent (higher in 

processed XRF sample), manganese 78 percent (higher in processed XRF sample), zinc 

81 percent (higher in processed XRF sample). 

In sediment samples (all processed before XRF screening), arsenic, manganese, iron, and 

zinc were consistently biased high in the XRF screening compared to laboratory data. Where 

detected by either the laboratory or XRF screening, chromium also appears to be biased high in 

the XRF screening. Detected concentrations with calculated RPDs that exceeded control limits 

have been flagged with a “J+” in Table 9, indicating that the XRF screening result is an 

estimated quantity, but the result may be biased high. 

10.2 FIELD QUALITY CONTROL 

Field QC measures used during the investigation consisted of the following: daily 

calibrations for each field instrument (results of which were recorded on forms provided in 

Attachment 6); adherence to field standard operating procedures (SOPs) for collection of 
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samples; and collection of field QC samples for submittal to the analytical laboratory. Field QC 

samples were collected during groundwater, surface water, sediment, and soil sampling to assess 

the accuracy and precision of the analytical data. These samples included trip blanks, field 

duplicates, and Matrix Spike/Matrix Spike Duplicates (MS/MSDs). The collection of QC 

samples and the acceptance criteria for these samples is described below. 

Hold Times – All samples were analyzed within recommended hold times. 

Trip blanks – One trip blank was included with the single shipment of aqueous sampling 

containers. It was prepared in the laboratory by filling a metals sampling bottle with deionized 

water and preservative and sealing the container. The trip blank accompanied the sample bottles 

to the Site and remained unopened in the shipping container until the sample bottles were 

received at the laboratory. As summarized in Table 12, zinc was reported in the surface water 

trip blank at an estimated concentration (below the laboratory reporting limit) of 2.7 ug/L. Zinc 

was also reported in the laboratory method blank, suggesting that the detection reported for the 

trip blank was a result of laboratory contamination. 

Field duplicates and triplicates – Field replicates were collected at a frequency of one 

duplicate for every 20 or fewer samples of each medium (soil, sediment, surface water, or 

groundwater) submitted for analysis. Samples for aqueous field duplicates were collected 

consecutively, with the replicate sample collected immediately following collection of the 

primary sample. For soil and sediment samples, a field duplicate was prepared by collecting a 

second subsample from a single processed (dried and sieved) soil sample. 

One triplicate multi-increment sample was collected and analyzed. The triplicate sample 

was collected by consecutively sampling the same decision unit three times. Sampling 

equipment was decontaminated after collection of the primary and duplicate samples. 

As specified in the QAPP, field duplicate RPDs are considered acceptable if they are less 

than 30 percent for aqueous samples and less than 50 percent for solid samples. For multi-
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increment sampling, the relative standard deviation (RSD) between the triplicate sample results 

was considered acceptable if it was 30 percent or less. RPDs were calculated only if the 

laboratory reported a detection above the reporting limit in both the primary and duplicate 

samples. 

Based on the comparative analysis of concentrations reported for each primary and 

duplicate sample (Tables 4, 7, 8, and 9), results were within the acceptable RPD criteria, with the 

following exception: 

• MW-J4-S (groundwater) - copper 36 percent. 

RSDs calculated for the multi-increment sample triplicate were within acceptable RPD 

criteria with the following exceptions: 

• cadmium 34 percent and zinc 35 percent. 

Detected concentrations outside respective control limits have been “J” flagged 

(estimated) in Tables 2 (background soil) and 7 (groundwater). 

Matrix Spike/Matrix Spike Duplicates – Additional sample volumes for MS/MSD 

samples were collected at a minimum frequency of one per every 20 or fewer samples of each 

matrix. MS/MSD acceptance criteria were determined by the laboratory, as detailed in the 

QAPP. A discussion of MS/MSD results for samples in each medium follows. 

Sediment 

Spike recoveries for arsenic, copper, iron, manganese, and zinc could not be assessed in 

the sediment sample submitted for MS/MSD analysis because the primary sample contained 

concentrations of these metals that were more than four times the spike amount. Recoveries for 

all other analytes were within acceptable limits. 

Surface Water 
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MS/MSD analysis was performed on two surface water samples: SW-J22, collected from 

the Main Branch of Cabin Creek; and SW-J29, collected from the South Branch of Cabin Creek. 

Samples were spiked for all target analytes. All spike recoveries were within acceptable limits. 

Groundwater 

Groundwater sample MW-J5 was designated for MS/MSD analysis. This sample was 

spiked for all targeted analytes. All spike recoveries were within acceptable limits. 

Background Soils 

The SS-Dup sample (collected from location SS-J3) was submitted for MS/MSD 

analysis. As summarized in Table 2, recoveries for copper, iron, lead, manganese, and zinc 

could not be assessed because the primary sample contained concentrations of these metals that 

were more than four times the spike amount. In the MS sample, arsenic spike recovery was 

higher than laboratory acceptance limits of 125 percent (144 percent ). In the MSD sample, 

arsenic recovery was low (27 percent) but considered within acceptable limits by the laboratory. 

Arsenic data from this QC batch, which includes all background MI samples, are qualified as 

estimated (“J”). Chromium recovery was below acceptance criteria in both the MS and MSD 

samples (0% and 6.1%, respectively). Chromium data from this batch are qualified as estimated, 

but the result may be biased low (“J-“). All other spike recoveries were within acceptable limits. 

Surficial Soil Sample 

Sample DS-218, collected during the tailings delineation sampling, was submitted for 

MS/MSD analysis. However, this sample was not used for the MS/MSD analyses due to a 

laboratory oversight. Instead, a sample from a separate project, which is not representative of the 

soil matrix at the Site, was used for the preparation batch. No data qualifiers have been applied 

to the results for the surficial soil samples (DS-201, 139, 220, 190, and 167). 

Subsurface Soil Samples 

One soil sample from beneath the tailings was designated for MS/MSD analysis: SB-J12 

(2.7-3.2’). As summarized in Table 4, recoveries for arsenic, copper, iron, manganese, or zinc 
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could not be assessed because the original sample contained concentrations of these metals that 

were more than four times the spike amount. All other spike recoveries were within acceptable 

limits, with the exception of vanadium in the MS sample, which was higher than the laboratory 

acceptance criteria of 39 to 129 percent, but the duplicate sample recovery was within the 

acceptance range. Vanadium data from this batch are qualified as estimated (“J”) (Table 4). 

10.3 LABORATORY QUALITY CONTROL 

The analytical laboratories used for this investigation have QC programs in place to 

ensure the reliability and validity of the analyses performed at the laboratory. Laboratory QC 

narratives were provided and reviewed. Relevant laboratory QA/QC protocols were followed 

per the QAPP and were acceptable. 

As part of the laboratory QC measures, a Performance Evaluation (PE) sample was 

submitted for analysis of the list of target metals in groundwater: arsenic, barium, cadmium, 

chromium, copper, iron, lead, nickel, selenium, silver, vanadium, and zinc by EPA Method 6020, 

and mercury by EPA Method 7041A. The PE sample was prepared by Environmental Resource 

Associates of Arvada, Colorado to contain a certified concentration of each target metal. As 

summarized in Table 12, results of the PE sample analyses were acceptable for all analytes. 

Differences between the certified concentrations and the laboratory reported results ranged from 

0 to 9 percent. 

10.4 DATA USABILITY 

With the exception of the issues summarized above, all other quality control results met 

acceptance criteria. All data are considered usable for the purposes of this investigation, based 

upon review of the results and the overall DQOs outlined in the QAPP. However, concentrations 

of some constituents from certain samples should be treated as estimates. 

11. SAMPLE DOCUMENTATION, PACKAGING, AND CUSTODY 

REQUIREMENTS 

This section describes the sample collection protocols required to satisfy the DQOs for 

this field effort. 
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11.1 SAMPLE COLLECTION DOCUMENTATION 

During field work, field forms and chain-of-custody (COC) records were completed by 

the field team to maintain a comprehensive record of sample collection, transfer of samples 

between personnel, shipment of samples, and receipt by the laboratory. 

11.2 FIELD NOTES 

Field notes and forms were completed to document all field activities. Sufficient data 

and information were recorded to reconstruct field activities for each specific day. All field 

forms were collected at the end of each day or as appropriate by the Sampling Team Leader. All 

entries were made in indelible ink. A Daily Log was completed at the end of each day to track 

personnel on site, as well as general field tasks completed or ongoing for each day. Daily logs 

are included in Attachment 5, and copies of the field notes and forms are included in Attachment 

6. 

11.3 SAMPLE PACKAGING AND SHIPPING 

Samples for laboratory analysis were placed in containers and preserved in accordance 

with Table 9-1 of the QAPP. The samples were packaged for shipment in protective media (i.e., 

bubble-wrap) and shipped to the laboratory via commercial carrier. 

11.4 CUSTODY PROCEDURES 

11.4.1 FIELD CUSTODY PROCEDURES 

The field sampler was responsible for the care and custody of field samples until they 

were transferred or dispatched. Field procedures were designed such that as few people as 

possible maintained custody and/or handled the field samples. 

Sample containers were identified using sample labels on which were recorded sample 

numbers, sampling locations, date/time of collection, and type of analysis. Sample labels were 

completed using waterproof ink unless prohibited by weather conditions. 

All samples were shipped with an accompanying COC form that listed sample 

identifications and locations. Individuals involved in the transfer of samples (i.e., relinquishing 

and receiving individuals) signed, dated, and noted the time of transfer on the COC. The COC 
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forms documented transfer of custody of samples from the field sampler to another person, to the 

laboratory, or to/from a secure storage location. 

A custody seal was attached to the outside of each shipping container such that the seal 

needed to be broken to access to the container, thus providing evidence of any unauthorized 

access. All samples were shipped under accompanying COC pursuant to JCO SOP “Chain-ofCustody Procedures”. All shipped containers were received with the custody seals intact. 

For the samples that were sent by common carrier, a copy of the waybill has been 

retained as part of the permanent documentation. Commercial carriers are not required to sign 

COC forms because the COC forms are sealed inside the shipping container and sealed with the 

custody seals. 

Due to the difficulty of transporting samples from the Site, all chemical samples were 

shipped to the laboratory in a single shipment immediately following completion of the field 

effort. Tailings samples for geotechnical analysis were delivered to the geotechnical laboratory 

immediately following their collection, while the rest of the geotechnical samples were delivered 

to the laboratory following completion of the field effort. 
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12. REFERENCES 

Alaska Department of Environmental Conservation, 2008. 18 AAC 75 Oil and Other Hazardous 

Substances Pollution Control, October 9, 2008. 

Alaska Department of Environmental Conservation, 2009. Technical Memorandum: Arsenic in 

Soil, March 2009. 

Shannon & Wilson, Inc., 2000. Final Engineering/Cost Analysis: Nabesna Mine Tailings, 

Wrangell-St. Elias National Park & Preserve, Nabesna, Alaska, November, 2000. 

URS, 1995. Site Inspection Report for the Nabesna Mine, URS Consultants, Inc. September, 

1995. 

U.S. Environmental Protection Agency, 2006. Guidance on Systematic Planning Using the Data 

Quality Objectives Process EPA QA/G-4. February, 2006. 

U.S. Geological Survey, 1999. Geochemical Data for Environmental Studies of Mineral 

Deposits at Nabesna, Kennecott, Orange Hill, Bond Creek, Bremner, and Gold Hill, 

Wrangell-St. Elias National Park and Preserve, Alaska. United States Geological 

Survey. 1999. 

WGM, 1981. Map: Rambler Mine Project, Nabesna Mill Tailings Base Map, WGM Inc. 

October, 1981. 
AR000161

TABLES 
ATTACHMENT 1 

PHOTOPLATES 
ATTACHMENT 2 

BOREHOLE LOGS 

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AR000280

ATTACHMENT 3 

CULTURAL RESOURCE MONITORING REPORT 
AR000281

ARCHAEOLOGICAL MONITORING OF SUPPLEMENTAL SITE 

INVESTIGATION 

NABESNA MINE SITE 

WRANGELL-ST. ELIAS NATIONAL PARK AND PRESERVE 

Report prepared for: 

The Johnson Company 

100 State Street, Suite 600 

Montpelier, VT 05602 

Report prepared by: 

Howard L. Smith, M.A. 

NORTHERN LAND USE RESEARCH, INC. Peter M. Bowers, M.A., R.P.A., Principal Investigator 

600 University Avenue, Suite 6 

Fairbanks, Alaska 99709 

February 2011 
AR000282

CONFIDENTIALITY NOTICE 

The locations of cultural resources given in this report are provided to facilitate environmental 

and engineering planning efforts only. Under the provisions of the Archaeological Resources 

Protection Act and the National Historic Preservation Act, site location information is 

confidential; disclosure of such information is exempt from requests under Federal and State 

freedom of information laws. This report is not a public document. It is intended for release to 

the Johnson Company, National Park Service, SHPO, and appropriate permitting agencies only. 

i 
AR000283

TABLE OF CONTENTS

Confidentiality Notice.................................................................................................................... i 

Table of Contents .......................................................................................................................... ii 

List of Figures ................................................................................................................................ ii 

1.0 Introduction....................................................................................................................... 1 

1.1 Project Setting....................................................................................................................... 1 

1.2 Area History.......................................................................................................................... 2 

2.0 Monitoring and Testing Methods .......................................................................................... 3 

2.1 Sampling Activities ............................................................................................................... 3 

2.2 Non-Sampling Activities ...................................................................................................... 4 

3.0 Monitoring and Testing Results ............................................................................................ 5 

4.0 Summary and Recommendations .......................................................................................... 6 

4.1 Limitations ............................................................................................................................ 6 

References...................................................................................................................................... 8 

LIST OF FIGURES

Figure 1. Map of the Nabesna area, showing the relationship of the mine to surrounding 

geographic features. ................................................................................................................ 9 

Figure 2. View toward the west showing the upper tailings area in relationship to the mill 

building. ................................................................................................................................ 10 

Figure 3. Map of project area showing locations of drill holes and other features referenced in 

text......................................................................................................................................... 11 

Figure 4. Hollow stem auger drill rig at test boring SB-J5, in upper tailings area. Crew is in the 

process of retrieving a split spoon sample. ........................................................................... 12 

Figure 5. Air-rotary drill rig beginning drilling for monitoring well MW-J1. ............................. 12 

Figure 6. Typical surface disturbance from X-Ray florescence sampling. The field book shown 

measures 19 cm (7.5 in.) long............................................................................................... 13 

Figure 7. Location from which a hand-dug sample of tailings was removed to assess gold 

content. Field book shown measures 19 cm (7.5 in.) long. .................................................. 13 

Figure 8. View of the decontamination station looking north. ..................................................... 14 

Figure 9. Temporary drum storage area........................................................................................ 14 

Figure 10. Looking toward the northeast across lower staging area at NAB-292. The cabin is 

visible in the brush on the far side of the equipment and supplies. ...................................... 15 

Figure 11. Wooden object exposed in erosion channel near SB-J15. ........................................... 15 

ii 
AR000284

1.0 INTRODUCTION 

The National Park Service (NPS) is conducting environmental investigations pursuant to its 

authorities under the Comprehensive Environmental Response, Compensation, and Liability Act 

(CERCLA), 42 U.S.C. §§ 9601 et seq., in the vicinity of the Nabesna Gold Mine National 

Historic District (NAB-011), which is located within the Wrangell-St. Elias National Park and 

Preserve. These investigations are in response to NPS concerns over possible threats to human 

health and the environment resulting from conditions at the site. NPS contracted with The 

Johnson Company (Johnson) to complete an Engineering Evaluation/Cost Analysis (EE/CA) to 

evaluate alternatives for remediation of tailings associated with the mine. NPS determined that 

additional data was needed to complete the EE/CA and conducted a multi-faceted sampling 

effort during the summer of 2009 to acquire the needed information (Johnson Company 2009:1). 

As part of its compliance with Section 106 of the National Historic Preservation Act for that 

sampling effort, NPS required that an archaeological monitor be present during any significant 

surface-disturbing activities. Johnson contracted with Northern Land Use Research, Inc. (NLUR) 

to provide those monitoring services. NLUR personnel monitored operations in the vicinity of 

the historic mine during the entire sampling effort, which occurred during the period of August 

10 to August 28, 2009. All surface-disturbing activities were monitored by either NLUR 

Associate Archaeologist Howard Smith, M.A., or NLUR Associate Archaeologist Charles 

Holmes, PhD. 

1.1 Project Setting 

The Nabesna gold mine is located about five miles west of the Nabesna River, on the eastern 

slope of White Mountain, between Jack and Jacksina creeks (Figure 1). Access to the area is via 

a 46-mile unpaved road that connects to the Tok Cutoff at milepost 60. The mill building and 

other developments are located on private land at and above 3,000 ft. Mine tailings extend down 

slope to the east, covering an area of approximately nine acres, primarily on lands managed by 

the NPS (NPS 2001:3). The Nabesna mine access road crosses the tailings, dividing them into 

upper and lower regions. Figure 2 shows a general view of the mine and adjacent tailings. 

Cabin Creek, a small tributary of Jack Creek, runs immediately to the south of the mine. Except 

during periods of high water, Cabin Creek is an intermittent stream (NPS 2001:12). The mine 

and tailings areas are located on an alluvial fan associated with the creek (NPS 2001:13). 

Vegetation in the vicinity of the mine is primarily open spruce forest composed of white spruce 

interspersed with black spruce (NPS 2001:14). Vegetation noted during NLUR monitoring 

activities included spruce (Picea spp.), balsam poplar (Populus balsamifera), willows (Salix 

spp.), alders (Alnus sp.), wild rose (Rosa acicularis), blueberry (Vaccinium uliginosum), high 

bush cranberry (Viburnum edule), Labrador Tea (Ledum palustre), baneberry (Actaea rubra), 

Arctostaphylos sp., and crowberry (Empetrum nigrum). Various grasses, sedges, mosses, and 

lichens are also common. 

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1.2 Area History 

The history of mining developments in the Nabesna area has been described in considerable 

detail in a number of sources. Wayland (1943) contains a brief sketch of the mine’s history based 

on United States Geological Survey publications and information gathered from a 19-day visit to 

the mine in 1940. The National Register nomination form (Stanley 1978) includes information 

derived in part from reports of the Nabesna Mining Corporation and from personal papers of 

Carl F. Whitman, president of the corporation. Perhaps the most detailed history available to 

NLUR at this time is an unpublished manuscript entitled “Gold Mining in the Nabesna River 

Region” (Bleakley n.d.) that was supplied by the NPS office in Copper Center. This manuscript, 

which may be part of a larger report, includes published and unpublished sources and 

information from Alaska newspapers. The following historical sketch is based on these sources. 

The initial discovery of lode gold near the head of Jacksina Creek dates to 1899. Claims were 

first staked in 1903 by a miner named Field (sometimes Fjeld). In 1905 Field and another miner 

named Paulson formed the Royal Gold Mining Company, and in 1906 they hauled a three-stamp 

mill to the property via dog sled from Valdez. The stamp mill is apparently still at the mine site. 

In 1907, the Royal Development Company processed about 60 tons of ore, but gold recovery 

was insufficient to meet costs, and while they continued work for several more years, they never 

managed to make the mine profitable. In 1914, they allowed the claims to lapse. For the next 

several years different individuals prospected in the area with little result. 

In 1924, Whitman filed on the claims, and in the following year discovered the first of the major 

gold veins to be located in the area. Whitman continued working the mine for the next several 

years, and in 1929 formed the Nabesna Mining Corporation (NMC). For the next few years after 

that, NMC developed the mine, digging several hundred feet of shafts, constructing support 

buildings, and expanding milling capacity. 

Significant production at the Nabesna mine apparently started in 1933, the same year in which 

the road was completed connecting the mine to the Richardson Highway. Peak production was 

reached in the late 1930s, at which time the mine employed 60 to 70 men and processed more 

than 5,000 tons of ore annually. 

In late 1939, faced with severely declining ore reserves, the NMC suspended operations for the 

winter, opening again the following year, but producing only a small fraction of what it had the 

previous year. The company continued development work on the property in 1941, but no ore 

was processed. In 1942 the mine closed as the government terminated all non-essential mining in 

response to World War II. It has not operated since. 

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2.0 MONITORING AND TESTING METHODS 

Personnel from NLUR (either Howard L. Smith, M.A., R.P.A., or Charles Holmes, Ph.D., 

R.P.A.) were present at the Nabesna gold mine site from August 10 to August 28, 2009. During 

this period, a series of different sampling activities were monitored, a very limited amount of 

surface inventory was conducted in advance of certain surface-disturbing activities, and some 

non-sampling activities were observed. Frequently, one or more sampling procedures were 

carried out simultaneously, but the pace and nature of the activities allowed a single individual to 

adequately monitor the program. 

2.1 Sampling Activities 

Sampling procedures consisted of soil test borings, drilling, and construction of water quality 

monitoring wells, surficial soil sampling to delineate mine tailings, collection of a limited 

number of hand-dug samples to evaluate the gold content of the tailings, and collection of 

surface water and sediment samples. NLUR monitors actively observed all of these procedures 

except for surface water and sediment sampling, which involved no potential for significant 

surface disturbance. Figure 3 is a map of the project area, showing the area in which sampling 

occurred, and specific locations of the drill holes. 

The two drilling programs, and the concomitant need to move drill rigs on and near the tailings, 

posed the highest potential for impacts to historic materials. Two drill rigs were utilized 

simultaneously, both mounted on flex-tracked Nodwell vehicles. One was a rotary-driven hollow 

stem auger, used primarily for the soil test borings. The second rig, which was used primarily for 

the monitoring wells, was an air rotary machine. Figures 4 and 5 show the two rigs in operation 

at the mine site. 

For the drilling programs, monitoring consisted of several discrete steps. First, prior to the 

beginning of any sampling activities, Johnson Company personnel marked prospective drill sites 

with flagged pins and also flagged several surface occurrences of historic material to facilitate 

avoidance. As drilling progressed, NLUR personnel used survey flagging to mark additional 

locations containing historic debris in the vicinity of proposed drill sites. Second, prior to any 

drilling, a representative of Johnson and the NLUR monitor inspected access routes to each drill 

site, and developed an acceptable route. The NPS furnished a detailed map resulting from past 

archaeological survey of the area, which was a significant aid in identifying and avoiding historic 

remains. Third, the NLUR monitor observed the drill rig during any movement on the upper 

tailings, where almost all of the known historic materials were located, and during most or all of 

the movement elsewhere. Finally, NLUR monitors used digital cameras to record each bore hole 

location, before and after drilling. 

Water quality monitoring wells were laid out in two general locations. Four wells were drilled on 

the uphill side of the mine access road and another five on and adjacent to the lower tailings 

(Figure 3). Five of the monitoring wells were located in undisturbed areas either immediately 

adjacent to the access road or on the margins of the lower tailings. NLUR monitors inspected all 

well locations in undisturbed areas prior to drilling, monitored the movement of rigs into the 

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areas, and observed drilling in progress. As with soil test bore holes, digital images were 

obtained prior to and drilling and after the rig had vacated the site. 

Monitoring wells were drilled to groundwater and, therefore, were much deeper than soil test 

bore holes. Once groundwater was reached, considerable time and effort was needed to construct 

the well. As a result, the drill rig utilized for monitoring wells moved much less frequently than 

the one drilling soil test bore holes. As a general rule, soil tests proceeded at a rate of one or two 

borings per day, while monitoring wells were completed at a rate of one every two or three days. 

This pace made it possible for a single monitor to keep track of activities at two different drilling 

locations, plus have ample time to inspect access routes and drilling locations ahead of time, and 

to monitor other activities. 

Tailings delineation was conducted utilizing an X-ray fluorescence (XRF) analyzer, and involved 

minimal surface disturbance. Originally, the intent was to gather small soil samples that would 

be transported back to the lodge, dried in an oven and then analyzed for iron, arsenic, and lead 

content. After a small number of samples were processed in this fashion, Johnson personnel 

determined that adequate data could be obtained by conducting on-site testing with the XRF 

analyzer. Consequently the bulk of tailings delineation involved clearing vegetation from a small 

area (seldom more than 10 cm2

) then the XRF analyzer was placed in contact with the soil and 

readings were taken. Figure 6 shows a typical surface disturbance resulting from this sampling 

activity. Coordinates for each sample site were obtained using a GPS receiver with sub-meter 

accuracy. Toward the bottom of the lower tailings area, wetter soils were encountered, and a 

hand auger was used to retrieve samples for XRF data. This resulted in somewhat less surface 

disturbance, but deeper penetration. The bulk of the tailings delineation work occurred after the 

drilling program was completed, and could consequently be observed closely by the NLUR 

monitor. 

One final sampling activity involved the collection of a number of hand-dug samples of tailings 

material to determine the gold content. This sampling was conducted by personnel from Kinross 

Gold from Fairbanks, and involved the excavation of a small trench using short-handled shovels. 

A small amount (no more than 0.5 ft3) of material was removed from each trench and placed in a 

plastic bucket to be transported off-site for analysis. This sampling was conducted on August 12, 

when the drilling program was just commencing. Consequently, it was only possible to directly 

observe hand sampling in the top part of the upper tailings area. Almost all of the known historic 

debris is located in this area, so hand sampling was actively monitored in the locations most 

likely to conflict with cultural resources. Because this activity involved minimal surface 

disturbance and was carried out only in disturbed areas, NLUR personnel concluded it was not 

necessary to directly monitor sampling in those portions of the tailings containing few or no 

known historic materials. The small trenches left by hand sampling were inspected. Figure 7 

shows one of the locations sampled in this manner. 

2.2 Non-Sampling Activities 

NLUR monitors observed some non-sampling activities as well. There were three activity areas 

where foot and vehicle traffic was concentrated enough to entail some potential for surface 

disturbance, and a crew of two surveyors were on site for two days to obtain precise locations 

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and elevations associated with the project. The first concentrated activity area consisted of a 

decontamination station located adjacent to the road at the lower end of the upper tailings, 

essentially at the same spot as monitoring well MW-J6. This area was used to clean boots, ATVs 

and other vehicles, and the drill rigs and drilling equipment prior to any of them leaving the 

tailings area. This location was used on a daily basis and sustained a significant amount of 

traffic. Figure 8 shows the decontamination station. 

All the wash water generated by decontamination, cuttings produced by drilling, used absorbent 

pads and any other potentially hazardous materials were placed in drums and stockpiled for 

future disposal. An area across the road and northeast of the decontamination station was cleared 

of large vegetation and used to collect these drums. A moderate amount of foot and ATV traffic 

took place in the stockpile area. The drum collection area is shown in Figure 9. 

A third concentrated activity area was located on the northern margin of the lower tailings area, 

along an existing road and trail and next to a single log cabin and associated artifact scatters 

(NAB-292). According to the Alaska Heritage Resources Survey database, the site is named 

“Little Al’s Cabin” and dates to the 1950s. This area was used to park ATVs and as a short-term 

storage area for tools and equipment used in the various sampling activities on the lower tailings. 

Figure 10 shows the third activity area. 

NLUR monitors inspected all three activity areas prior to any significant amount of use. In the 

case of the area adjacent to NAB-292, the cabin and surrounding artifact scatters were 

periodically examined to determine if anything had been disturbed. 

The survey crew established a GPS base station in the vicinity of NAB-292, and two slave units 

along the edge of the Nabesna Road. A roving GPS unit on a tripod was then set up on each 

point to be located, and allowed to gather data for a period of five minutes before being moved to 

the next point. The stationary units were installed using small personal ATVs, while the roving 

unit was transported by foot. A monitor accompanied the survey crew as they located points in 

the top portion of the upper tailings area. 

3.0 MONITORING AND TESTING RESULTS 

All activities observed by NLUR monitors were conducted without significant impacts to historic 

or prehistoric resources. Several aspects of the project contributed to the minimization of 

impacts. First, the vast majority of the sampling activities took place in previously disturbed 

areas covered by mine tailings, reducing the potential for impacts. Because the tailings are 

largely devoid of vegetation, surface artifacts were easily seen. Where activities did take place in 

undisturbed areas, NLUR monitors inspected the locations prior to use. No cultural materials 

were discovered as a result of these inspections. 

Second, previous work done by NPS archaeologists had located numerous historic artifacts. This 

inventory appeared to be thorough and accurate. NLUR monitors noted only a few historic 

objects that were not included in the NPS inventory, and these were largely the result of erosion 

that more than likely exposed them since the NPS inventory was done. NPS furnished the NLUR 

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monitors with a detailed map and description of known historic materials, which helped to locate 

and avoid them. 

Third, the design and location of sampling activities were such as to reduce the likelihood of 

impacts. Hand sampling and X-ray fluorescence analysis involved little surface disturbance and 

were inherently unlikely to impact historic materials to any significant degree. The drilling 

program clearly involved enough surface disturbance to pose a threat, but was mostly located 

away from concentrations of historic debris. Almost all known historic objects are located near 

the top part of the upper tailings area, and most of these in the brushy areas to the north and 

south of the tailings. Only a few sampling activities took place in the vicinity of these known 

historic materials. Where they did –in the vicinity of soil tests SB-J4, SB-J7, SB-J8, SB-J9, and 

SB-J15 – historic materials were distributed in such a manner that it was possible to avoid them 

and still access the drill hole locations. 

No operation of the sort described here can be conducted completely without impacts and NLUR 

monitors did observe some disturbance of cultural materials. On three occasions small isolated 

pieces of wood or lumber were disturbed by operations. Twice, drill rigs crushed small pieces of 

lumber that were obscured by vegetation and consequently had not been observed prior to rig 

movement. In a third instance, an NLUR monitor manually moved a deteriorated piece of wood 

to allow the drill to pass, and returned it once the drilling was completed. This piece of wood was 

located in an erosion channel and likely had been redeposited. These are extremely minor 

disturbances and do not represent a significant impact on the historic property at the mine. 

By far the largest impact to the area around the historic district resulted from the tracks left by 

the drill rigs as they moved across the tailings. To the extent that the tailings are a contributing 

element to a historic mining landscape, the tracks do represent a limited and transitory impact. 

The tracks are only noticeable from a short distance, and do not constitute a visual intrusion from 

a medium or long distance. For example, looking toward the mill building from the bottom of the 

upper tailings, the tracks are not particularly noticeable. Figure 2 shows this view after all 

drilling was completed. The surface of the tailings is unstable to a certain extent, and it is likely 

that normal surface erosion will obscure the tracks within a short period of time. 

4.0 SUMMARY AND RECOMMENDATIONS 

Northern Land Use Research, Inc. provided archaeological monitors to observe operations in the 

vicinity of the Nabesna Historic Mining District during August of 2009. Operations were 

conducted by The Johnson Company of Vermont, under contract to the National Park Service. 

Operations were conducted to gather information to help the Park Service evaluate alternatives 

for possible remediation of mine tailings. During the course of monitoring this project, NLUR 

observed no significant impacts to the historic property involved. 

4.1 Limitations 

This project was carried out, and this report prepared, in accordance with generally accepted 

professional practices for the nature and conditions of the work completed in the same or similar 

localities, at the time the work was performed. It is intended for the exclusive use of The 

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Johnson Company and NPS for specific application to the referenced project. It should be noted 

that NLUR relied upon information and/or verbal accounts provided by the agencies and 

individuals indicated in the report. NLUR can only relay this information and cannot be 

responsible for its accuracy or completeness. This report is not meant to represent a legal 

opinion. 

We do not warrant that we have identified all potentially significant cultural resources present at 

the referenced properties, as these may be hidden in such a way that only extensive excavations, 

use of remote sensing equipment (e.g., ground penetrating radar, magnetometer), or other 

technologies/methods not included in our scope of work will reveal them. No other warranty, 

express or implied, is made. Any questions regarding our work and this report can be directed to 

NLUR Operations Manager Burr Neely or to NLUR Principal Archaeologist Peter Bowers. 

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REFERENCES 

Bleakley, Geoffery T. 

n.d. Gold Mining in the Nabesna River Region. In In the Shadow of Kennecott: A History of 

Mining in the Wrangell-St. Elias Mountain Region, 1898-1998, pp. 135-144. 

Unpublished report, Wrangell-St. Elias National Park and Preserve. 

Bowers, Peter M. 

2009 Nabesna Mine Archaeological Monitoring Project. Letter report prepared for The 

Johnson Company by Northern Land Use Research, Inc., Fairbanks. 

The Johnson Company 

2009 Field Sampling Plan, Nabesna Mine Site Supplemental Site Investigation (SSI). The 

Johnson Company, Montpelier, VT. 

National Park Service 

2001 Environmental Assessment for a Phased Mitigation Plan for the Nabesna Mine Tailings. 

Ms. On file, Wrangell-St. Elias National Park and Preserve, Copper Center. 

Stanley, Kirk W. 

1978 Nabesna Gold Mine Historic District (NAB-011). National Register Nomination form 

prepared by Kirk W. Stanley, the Ptarmigan Company, Anchorage. 

Wayland, Russell G. 

1943 Gold Deposits Near Nabesna. In Mineral Resources of Alaska: Report on Progress of 

Investigations in 1940, ed. by P. S. Smith, pp. 175-195. U. S. Geological Survey Bulletin 

933. 

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Figure 1. Map of the Nabesna area, showing the relationship of the mine to surrounding 

geographic features. 

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Figure 3. Map of project area showing locations of drill holes and other features referenced 

in text. 

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ATTACHMENT 4 

LABORATORY ANALYTICAL RESULTS 

AR000299
ANALYTICAL REPORT

PROJECT NO. 3-0700-6

NABESNA MINE SITE

Lot #: A9I010228

Rhonda Kay

The Johnson Company, Inc.

100 State St.

Montpelier, VT 05602

TESTAMERICA LABORATORIES, INC.

Patrick J. O'Meara

September 21, 2009

AR000300

ANALYTICAL REPORT 

PROJECT NO. 3-0700-6 

NABESNA MINE SITE 

Lot #: A9I010228 

Rhonda Kay 

The Johnson Company, Inc. 

100 State St. 

Montpelier, VT 05602 

TESTAMERICA LABORATORIES, INC. 

_____________________________________________ 

Patrick J. O'Meara 

Project Manager 

Approved for release. 

Patrick O'Meara 

Project Manager 

9/21/2009 1:11 PM 

patrick.omeara@testamericainc.com 

September 21, 2009 

TestAmerica Laboratories, Inc. 

TestAmerica North Canton 4101 Shuffel Street NW, North Canton, OH 

44720 Tel (330)497-9396 Fax (330)497-0772 

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CASE NARRATIVE

 A9I010228 

The following report contains the analytical results for twenty-seven water samples and 

one quality control sample submitted to TestAmerica North Canton by The Johnson 

Company, Inc. from the Nabesna Mine Site, project number 3-0700-6. The samples were 

received September 01, 2009, according to documented sample acceptance procedures. 

TestAmerica utilizes USEPA approved methods in all analytical work. The samples 

presented in this report were analyzed for the parameter(s) listed on the analytical 

methods summary page in accordance with the method(s) indicated. Preliminary results 

were provided to Daniel Baston and Rhonda Kay on September 16, 2009. A summary of 

QC data for these analyses is included at the back of the report. 

TestAmerica North Canton attests to the validity of the laboratory data generated by 

TestAmerica facilities reported herein. All analyses performed by TestAmerica facilities 

were done using established laboratory SOPs that incorporate QA/QC procedures 

described in the applicable methods. TestAmerica's operations groups have reviewed the 

data for compliance with the laboratory QA/QC plan, and data have been found to be 

compliant with laboratory protocols unless otherwise noted below. 

The test results in this report meet all NELAP requirements for parameters for which 

accreditation is required or available. Any exceptions to NELAP requirements are noted 

in this report. Pursuant to NELAP, this report may not be reproduced, except in full, 

without the written approval of the laboratory. 

All parameters were evaluated to the method detection limit and include qualified results 

where applicable. 

Please refer to the Quality Control Elements Narrative following this case narrative for 

additional quality control information. 

If you have any questions, please call the Project Manager, Patrick J. O'Meara, at 330-

497-9396. 

This report is sequentially paginated. The final page of the report is labeled as "END OF 

REPORT." 

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CASE NARRATIVE (continued) 

SUPPLEMENTAL QC INFORMATION 

SAMPLE RECEIVING 

The temperatures of the coolers upon sample receipt were 16.4, 16.6, and 18.2°C, with no 

coolant present. 

See TestAmerica’s Cooler Receipt Form for additional information. 

METALS 

The sample(s) that contain results between the MDL and the RL were flagged with "B". 

There is the possibility of false positive or mis-identification at these quantitation levels. 

The acceptance criteria for the ICB, CCB, and Method Blank are +/- the standard 

reporting limit (SRL). 

The sample(s) that contained concentrations of target analyte(s) at a reportable level in 

the associated Method Blank(s) were flagged with "J". Refer to the sample report pages 

for the affected analyte(s). 

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QUALITY CONTROL ELEMENTS NARRATIVE 

TestAmerica conducts a quality assurance/quality control (QA/QC) program designed to provide scientifically valid and legally 

defensible data. Toward this end, several types of quality control indicators are incorporated into the QA/QC program, which is 

described in detail in QA Policy, QA-003. These indicators are introduced into the sample testing process to provide a mechanism for 

the assessment of the analytical data. Program or agency specific requirements take precedence over the requirements listed in this 

narrative. 

QC BATCH 

Environmental samples are taken through the testing process in groups called QUALITY CONTROL BATCHES (QC batches). A 

QC batch contains up to twenty environmental samples of a similar matrix (water, soil) that are processed using the same reagents and 

standards. TestAmerica North Canton requires that each environmental sample be associated with a QC batch. 

Several quality control samples are included in each QC batch and are processed identically to the twenty environmental samples. 

For SW846/RCRA methods, QC samples include a METHOD BLANK (MB), a LABORATORY CONTROL SAMPLE (LCS) and, 

where appropriate, a MATRIX SPIKE/MATRIX SPIKE DUPLICATE (MS/MSD) pair or a MATRIX SPIKE/SAMPLE 

DUPLICATE (MS/DU) pair. If there is insufficient sample to perform an MS/MSD or an MS/DU, then a LABORATORY 

CONTROL SAMPLE DUPLICATE (LCSD) is included in the QC batch. 

For 600 series/CWA methods, QC samples include a METHOD BLANK (MB), a LABORATORY CONTROL SAMPLE (LCS) and, 

where appropriate, a MATRIX SPIKE (MS). An MS is prepared and analyzed at a 10% frequency for GC Methods and at a 5% 

frequency for GC/MS methods. 

LABORATORY CONTROL SAMPLE 

The Laboratory Control Sample is a QC sample that is created by adding known concentrations of a full or partial set of target 

analytes to a matrix similar to that of the environmental samples in the QC batch. Multi peak responders may not be included in the 

target spike list due to co-elution. The LCS analyte recovery results are used to monitor the analytical process and provide evidence 

that the laboratory is performing the method within acceptable guidelines. All control analytes indicated by a bold type in the LCS 

must meet acceptance criteria. Failure to meet the established recovery guidelines requires the repreparation and reanalysis of all 

samples in the QC batch. Comparison of only the failed parameters from the first batch are evaluated. The only exception to the 

rework requirement is that if the LCS recoveries are biased high and the associated sample is ND (non-detected) for the parameter(s) 

of interest, the batch is acceptable. 

At times, a Laboratory Control Sample Duplicate (LCSD) is also included in the QC batch. An LCSD is a QC sample that is created 

and handled identically to the LCS. Analyte recovery data from the LCSD is assessed in the same way as that of the LCS. The 

LCSD recoveries, together with the LCS recoveries, are used to determine the reproducibility (precision) of the analytical system. 

Precision data are expressed as relative percent differences (RPDs). If the RPD fails for an LCS/LCSD and yet the recoveries are 

within acceptance criteria, the batch is still acceptable. 

METHOD BLANK 

The Method Blank is a QC sample consisting of all the reagents used in analyzing the environmental samples contained in the QC 

batch. Method Blank results are used to determine if interference or contamination in the analytical system could lead to the reporting 

of false positive data or elevated analyte concentrations. All target analytes must be below the reporting limits (RL) or the associated 

sample(s) must be ND except under the following circumstances: 

• Common organic contaminants may be present at concentrations up to 5 times the reporting limits. Common metals 

contaminants may be present at concentrations up to 2 times the reporting limit, or the reported blank concentration must be 

twenty fold less than the concentration reported in the associated environmental samples. (See common laboratory contaminants 

listed in the table.) 

Volatile (GC or GC/MS) Semivolatile (GC/MS) Metals ICP-MS Metals ICP Trace 

Methylene Chloride, Phthalate Esters Copper, Iron, Zinc, Copper, Iron, Zinc, Lead 

Acetone, 2-Butanone Lead, Calcium, 

Magnesium, Potassium, 

Sodium, Barium, 

Chromium, Manganese 

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QUALITY CONTROL ELEMENTS NARRATIVE (continued) 

• Organic blanks will be accepted if compounds detected in the blank are present in the associated samples at levels 10 times the 

blank level. Inorganic blanks will be accepted if elements detected in the blank are present in the associated samples at 20 times 

the blank level. 

• Blanks will be accepted if the compounds/elements detected are not present in any of the associated environmental samples. 

 Failure to meet these Method Blank criteria requires the repreparation and reanalysis of all samples in the QC batch. 

MATRIX SPIKE/MATRIX SPIKE DUPLICATE 

A Matrix Spike and a Matrix Spike Duplicate are a pair of environmental samples to which known concentrations of a full or partial 

set of target analytes are added. The MS/MSD results are determined in the same manner as the results of the environmental sample 

used to prepare the MS/MSD. The analyte recoveries and the relative percent differences (RPDs) of the recoveries are calculated and 

used to evaluate the effect of the sample matrix on the analytical results. Due to the potential variability of the matrix of each sample, 

the MS/MSD results may not have an immediate bearing on any samples except the one spiked; therefore, the associated batch 

MS/MSD may not reflect the same compounds as the samples contained in the analytical report. When these MS/MSD results fail to 

meet acceptance criteria, the data is evaluated. If the LCS is within acceptance criteria, the batch is considered acceptable. 

For certain methods, a Matrix Spike/Sample Duplicate (MS/DU) may be included in the QC batch in place of the MS/MSD. For the 

parameters (i.e. pH, ignitability) where it is not possible to prepare a spiked sample, a Sample Duplicate may be included in the QC 

batch. However, a Sample Duplicate is less likely to provide usable precision statistics depending on the likelihood of finding 

concentrations below the standard reporting limit. When the Sample Duplicate result fails to meet acceptance criteria, the data is 

evaluated. 

For certain methods (600 series methods/CWA), a Matrix Spike is required in place of a Matrix Spike/Matrix Spike Duplicate 

(MS/MSD) or Matrix Spike/Sample Duplicate (MS/DU). 

The acceptance criteria do not apply to samples that are diluted. 

SURROGATE COMPOUNDS 

In addition to these batch-related QC indicators, each organic environmental and QC sample is spiked with surrogate compounds. 

Surrogates are organic chemicals that behave similarly to the analytes of interest and that are rarely present in the environment. 

Surrogate recoveries are used to monitor the individual performance of a sample in the analytical system. 

If surrogate recoveries are biased high in the LCS, LCSD, or the Method Blank, and the associated sample(s) are ND, the batch is 

acceptable. Otherwise, if the LCS, LCSD, or Method Blank surrogate(s) fail to meet recovery criteria, the entire sample batch is 

reprepared and reanalyzed. If the surrogate recoveries are outside criteria for environmental samples, the samples will be reprepared 

and reanalyzed unless there is objective evidence of matrix interference or if the sample dilution is greater than the threshold outlined 

in the associated method SOP. 

The acceptance criteria do not apply to samples that are diluted. All other surrogate recoveries will be reported. 

For the GC/MS BNA methods, the surrogate criterion is that two of the three surrogates for each fraction must meet acceptance 

criteria. The third surrogate must have a recovery of ten percent or greater. 

For the Pesticide and PCB methods, the surrogate criterion is that one of two surrogate compounds must meet acceptance criteria. 

The second surrogate must have a recovery of 10% or greater. 

TestAmerica Certifications and Approvals: 

The laboratory is certified for the analytes listed on the documents below. These are available upon request. 

California (#01144CA), Connecticut (#PH-0590), Florida (#E87225), 

Illinois (#200004), Kansas (#E10336), Minnesota (#39-999-348), New Jersey (#OH001), New York (#10975), Nevada 

(#OH-000482008A), OhioVAP (#CL0024), Pennsylvania (#008), West Virginia (#210), Wisconsin (#999518190),NAVY, 

ARMY, USDA Soil Permit 

N:\QAQC\Customer Service\Narrative - Combined RCRA _CWA 032609.doc 

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