P.1 

OAR Box 1781 

Prepped by Ollie Stewart 

Document Number: 

9) 11-1-1 

Docket Number: 

A-90-37 

Printed 10/29/2008 10:46:18 AM Sheet 9 of 142 
P.2 

United States 

Department of 

Agriculture 

Forest Service 

Northeastern Forest 

Experiment Station 

General Technical 

Report NE-151 

ml 

TL-TJ-IL 

Screening Procedure to Evaluate 

Effects of Air Pollution on 

Eastern Region Wildernesses Cited 

as Class I Air Quality Areas 

Mary Beth Adams 

Dale S. Nichols 

C. Anthony Federer 

Keith F. Jensen 

Harry Parrott 
P.3 

Abstract 

The USDA Forest Service's Eastern Region manages eight wilderness areas that 

have been designated as Class I air quality areas by the Federal Clean Air Act. As 

part of this legislation, Federal land managers are required to consult with air 

pollution regulators on the potential impacts of proposed air pollution emissionsincluding phytotoxic gases and acidic materials—on the air quality-related values 

(AQRVs) of these wildernesses. Applications for Prevention of Significant 

Deterioration (PSD) permits must be reviewed and commented on by the Federal 

land manager. This publication provides the manager with a procedure to rapidly 

screen these applications to determine which should have detailed review. The 

screening approach is a regional modification of a national model developed by 

the Forest Service in 1988. In 1990, the Eastern Region, Northeastern and North 

Central Forest Experiment Stations, and the Northeastern Area, State and Private 

Forestry sponsored a workshop of scientists and land managers to obtain advice 

on regionalizing this screening procedure. Two loading levels for various 

pollutants were established. The "red line" is the loading level above which 

AQRVs are expected to be adversely affected. The "green line" is the loading 

level below which no adverse impacts are expected. Within the intermediate 

"yellow zone" effects are uncertain. The publication describes the criteria used to 

establish red and green line values, the AQRVs for each wilderness, and the 

relation between the two. 

The Authors 

MARY BETH ADAMS is a Supervisory Soil Scientist with the USDA Forest 

Service, Northeastern Forest Experiment Station at Parsons, West Virginia. 

DALE S. NICHOLS is a Research Soil Scientist with the North Central Forest 

Experiment Station at Grand Rapids, Minnesota. 

C. ANTHONY FEDERER is a Research Forester with the Northeastern Forest 

Experiment Station at Durham, New Hampshire. 

KEITH F. JENSEN is a Supervisory Plant Physiologist with the Northeastern 

Forest Experiment Station at Delaware, Ohio. 

HARRY PARROTT is Regional Hydrologist with the USDA Forest Service's 

Eastern Region at Milwaukee, Wisconsin. 

Manuscript received for publication 1 February 1991 

Northeastern Forest Experiment Station 

5 Radnor Corporate Center 

100 Matsonford Road, Suite 200 

PO Box 6775 

Radnor, Pennsylvania 19087 

September 1991 
P.4 

Introduction 

Forest Service land managers need information about the 

effects of air pollution on wilderness areas that have been 

designated as Class I by the Clean Air Act (Public Law 

95-95). Regulations pursuant to that Act require that the 

U.S. Environmental Protection Agency and State air 

pollution emission regulators consult with "federal land 

managers" (FLMs) on potential impacts to the "air qualityrelated values" (AQRVs) of Class I areas. In turn, managers 

of Class I areas are required to review preconstruction 

applications for air pollution emission permits. Called 

Prevention of Significant Deterioration (PSD) permits, these 

are required for "major" new air pollution emission sources 

and major modifications of existing sources. Major is 

defined here as certain catagories of sources (for example, 

coal-fired power plants) emitting more than 100 ton/yr of any 

pollutant, or any other source emitting more than 250 ton/yr 

(42 U.S.C. 74779(1)). 

There are eight National Forest Class I air quality areas in 

the USDA Forest Service's Eastern Region (Region 9) (Fig. 

1). Each area, designated as wilderness before the 1977 

amendments to the Clean Air Act, is a mandatory Class I 

area because it is larger than 5,000 acres (Clean Air Act 

Sect. 162). 

The workshop upon which this report is based was 

preceded by a meeting of National Forest managers and 

scientists in 1988 at the Institute of Ecosystem Studjes, 

Millbrook, New York. At that workshop, attendees 

developed a green-yellow-red (G-Y-R) screening model (Fox 

et al. 1989) that suggests three alternative conclusions: 

• Adverse impacts are unlikely: pollutant loadings less than 

green line. 

• Uncertain impact: pollutant loadings in yellow zone. 

• Predicted adverse impact: pollutant loadings will exceed 

red line. 

The purpose of this report is to describe adaptation of a 

G-Y-R model for Eastern Region Class I areas, and to 

describe inventory and monitoring information needs and 

research needs identified by workshop attendees. 

Wilderness Act 

The Wilderness Act of 1964 (Public Law 88-557) established 

the National Wilderness Preservation System "to secure for 

the American people an enduring resource of wilderness." 

The Act describes wilderness as: 

...undeveloped Federal land retaining its primeval character 

and influence, without permanent improvements or human 

habitation, which is protected and managed so as to 

preserve its natural conditions and which generally appears 

to have been affected primarily by the forces of nature, 

where the influence of people is substantially unnoticeable. 

The Forest Service is responsible for ensuring the 

preservation of the wilderness character of congressionally 

designated National Forest wildernesses. Lightning-caused 

fires are allowed to burn under prescribed conditions, but 

roads, motorized equipment and mechanical transport, 

landing of aircraft, most commercial enterprises, and 

permanent structures and installations are prohibited. 

Special exceptions in some wilderness legislation allow for 

mineral exploration and development, access to private 

land, maintenance and use of airstrips, and, in Alaska, 

native use for subsistence. 

Clean Air Act 

The Clean Air Act (CAA) amendments of 1977 established a 

program for the prevention of significant deterioration of air 

quality. Certain wildernesses and National Parks established 

before August 1977 were designated by the CAA as 

mandatory Class I areas. A Class I designation allows small 

increments of additional air pollution above baseline levels 

within the area so long as the national ambient air quality 

standards are complied with and the AQRVs of the Class I 

area are not adversely affected. The baseline levels are 

those existing at the time of the first PSD application for an 

area (42 U.S.C. 7479(4)). The allowable increments are 

given in 42 U.S.C. 7473. Wildernesses established after 

August 7, 1977, are Class II areas, as is most of the 

country. Class II areas may receive a larger increment of air 

pollution. States may redesignate these Class II areas to 

Class I, but redesignation to Class I has not occurred for 

any Eastern Region National Forest Class II area. 

The CAA charges the FLM with responsibility for protecting 

the AQRVs of Class I areas. Addresses of Forest Service 

officials with responsibility for the Class I areas of the 

Eastern Region are included in Appendix II. AQRVs are 

features or properties that are important for preserving 

wilderness character and that could be adversely affected 

by air pollution. An adverse impact to AQRVs is defined as 

an impact of magnitude such that the purpose for which the 

area was established as wilderness will not be met. 

New source and major modification permit applicants 

submit plans to the air pollution emission regulatory 

authorities (EPA or State with EPA oversight). When a 

proposed source's emissions may have an impact on a 

Class I area, regulators are required to notify the FLM. The 

FLM then evaluates potential AQRV impacts and consults 

with the regulators on whether effects on the Class I area 

are adverse. A permit shall not be issued "in any case 

where the Federal Land Manager demonstrates to the 

satisfaction of the State that the emissions from such a 

facility will have an adverse impact on the air quality-related 

values (including visibility) of such lands..." (CAA Section 

165 (d)). A permit may be issued even if Class I increments 

will be exceeded, but Class II increments will be complied 

with "in any case where the owner or operator of such a 

facility demonstrates to the satisfaction of the Federal Land 

Manager, and the Federal Land Manager so certifies, that 

the emission increases will have no adverse impact to the 

air quality-related values of such lands (including visibility)..." 

(CAA Section 165 (d)). The FLM might have as few as 30 days 

to evaluate impacts to AQRVs and respond to the regulatory 

authority after a permit application is determined to be complete. 
ro Boundary Waters Canoe Area FORESTS AND CLASS I AIR QUALITY AREAS 

Lye^Brook Wilderness 

NATIONAL FORESTS 

EASTERN REGION 

ICAU 

100 

Hercules Glades Wilderness 

Figure 1.—Class I areas in USDA Forest Service's Eastern Region. 
P.6 

Regional Workshop Objectives 

Objectives of the Forest Service in holding the regional 

workshop were to: 

1. Obtain advice on screening criteria for the AQRVs of 

each Eastern Region Class I area. 

2. Publish a report that can be used by National Forest 

managers to identify screening criteria for assessing the 

impacts to AQRVs and that describes the rationale for 

criteria selection. 

Prior to this workshop, the National Forest staff had 

developed general wilderness and AQRV descriptions 

for the eight Class I wilderness areas (see Appendix I). 

Visibility, the only AQRV specifically mentioned in the 

Clean Air Act, is important in all of the Eastern Region 

Class I areas except Rainbow Lake Wilderness of the 

Chequamegon National Forest. However, establishing 

screening criteria for visibility is reserved for a separate 

national workshop. 

Scientists investigating the effects of air pollution on forest 

and aquatic ecosystems were invited to participate at the 

regional workshop, as were representatives of numerous 

organizations with an interest in forests, wilderness, air 

quality, and PSD permitting. Staff of the six Eastern Region 

National Forests with Class I air quality areas, the Regional 

Office, the Forest Service Southern Region, and the 

Washington Office also were invited. Workshop participants 

are listed in Appendix II. 

In developing PSD screening guidelines, terrestrial and 

aquatic ecosystems were initially considered separately. 

Workshop attendees were divided into terrestrial and 

aquatic ecosystem groups, and each group was subdivided 

into two teams which addressed the PSD screening process 

individually. Each ecosystem group met and identified areas 

of agreement and areas of divergent opinion and then 

developed inventory and monitoring information needs and 

priority research needs. Individual participants also offered 

advice to the chairperson of their team; chairpersons did not 

attempt to establish a consensus. 

Each ecosystem group approached the task differently, 

primarily because of differences in available information 

and current knowledge about the systems. The terrestrial 

ecosystem group determined that land managers can best 

determine impact criteria for terrestrial AQRVs and that the 

criteria will vary considerably among the Class I areas. Thus, 

the group focused on providing a decisionmaking framework and general resources for evaluating possible impacts 

on AQRVs. Because acidification effects on aquatic systems 

are better understood than for terrestrial systems, the aquatic 

ecosystem group concluded that sufficient information is 

available to establish red line-green line values for the eight 

Class I areas. 

Both terrestrial and aquatic ecosystem groups agreed on 

the need for certain basic information about current air 

quality and predicted changes. Participants in both groups 

noted the lack of basic information for the Class I areas and 

the uncertainty of current knowledge for predicting effects. 

Therefore, workshop products included identification of 

inventory and monitoring information needs and priority 

research needs. 

Screening Approach 

The following four-step screening approach was identified: 

1. Identify the AQRVs. The FLMs must do this. 

2. Obtain Resource Information. To evaluate a PSD 

application for possible effects on Class I area AQRVs, the 

FLM requires information including an inventory of flora and 

fauna (communities, species, and genera lists for both 

wildlife and plants, and threatened and endangered species 

present on the wilderness area); soils (pH of upper horizons, 

cation exchange capacity, base saturation, total bases); 

water resources (hydrology of lakes and streams, water 

chemistry information: pH, acid neutralizing capacity, base 

cations, sulfate, aluminum); and air quality (concentrations 

of ozone and sulfur dioxide, and estimates of nitrogen and 

sulfur loading to the ecosystems). If this information is not 

already available, obtaining this information should be an 

immediate priority. 

3. Determine Exposure of AQRVs to Air Pollution. 

Managers use predicted increment in emissions and current 

levels of air pollution exposure on the wilderness to 

calculate the total exposure (or loading) that can be 

expected as a result of aproposed facility. Applicants will 

provide information on the projected emissions from new 

facilities. If information on ozone, sulfur dioxide concentrations, and N and S loadings are not provided, the FLMs 

should immediately notify regulators that the application is 

incomplete. FLMs should request that regulators evaluate 

air pollution emissions and projections. The Forest Service 

may need to convert the information provided by the 

applicants to values that reflect effects on the the entire 

ecosystem. Cumulative atmospheric deposition should be 

considered and concentration values should be representative of usual ambient air quality and meteorological 

conditions and air pollution episodes. In case of doubt about 

usual conditions, worst-case air quality and meteorological 

conditions should be used. 

4. Determine Impact on AQRVs. The FLMs compare the 

total cumulative exposure with the evaluation criteria (red 

and green lines) for the sensitive wilderness components 

that are AQRVs. These criteria can be used, in consultation 

with the regulator, to determine if levels are: (1) Sufficiently 

high that impacts are predicted (above the red line); (2) 

Sufficiently low that impacts are not expected based on 

current knowledge (less than green line); or (3) Within the 

"yellow zone" and impacts are uncertain but the probability 

of adverse impacts increases as red-line criteria are 
P.7 

approached. It is critical that a cumulative impact analysis 

be done. Even with decreases in acidic air pollutant loading 

of Class I areas that may result from 1990 amendments to 

the CAA, adverse impacts on AQRVs can continue. Aquatic 

and terrestrial evaluations should be considered and 

compared according to the relative importance of specific 

AQRVs within the Class I area. 

Although workshop participants generally agreed 

to the approach described in this report, some individuals 

disagreed with the screening approach developed by Fox et 

al. (1989). PSD permit applicants may choose to use more 

complex modeling approaches and there by produce more 

precise answers. 

Current Levels of Pollution 

The PSD permit screening process focuses on two types of 

pollutants, phytotoxic gases and acidic materials. The 

phytotoxic gases of concern are ozone (O3) and sulfur 

dioxide (S02). The acidic pollutants include several forms of 

sulfur (S) and nitrogen (N). Data needs for the screening 

process are: 

1. Ozone: Second highest hourly average concentrations 

during the growing season. 

2. Sulfur: Average annual S02 concentrations or 3-hour 

maximum S02 concentrations; Total S deposition: 

precipitation, dry deposition, and cloud water deposition. 

3. Nitrogen: Total N deposition: precipitation, dry 

deposition, and cloud water deposition. 

Estimates of current air concentrations and deposition rates 

of these pollutants are shown in Tables 1-3. The ozone 

concentrations (Table 1) in some Class I areas were 

estimated from nearby monitoring stations in the EPA AIRS 

(Aerometric Information and Retrieval System) network 

(some analyses provided by Allen Lefohn, ASL Associates, 

Helena, MT), and from Forest Service ozone monitors near 

the Class I areas. Other ozone values were provided by the 

Appalachian Mountain Club, University of Massachusetts, 

and Wisconsin Department of Natural Resources. 

Mean annual S02 concentrations (Table 2) were derived 

from the Regional Acid Deposition Model (RADM) used by 

the National Acid Deposition Assessment Program (NAPAP) 

1990 assessment, and provided by Robin Dennis, 

Atmospheric Science and Modeling Division, U.S. EPA, 

Research Triangle Park, North Carolina. 

Table 1 .—Ozone concentrations, second highest 

1-hr average8 

Class I area 

Great Gulf/ 

Pres. Range-Dry River"5 

Lye Brook11 

Dolly Sods/Otter Creek 

Rainbow Lakec 

BWCAW 

Hercules Glades 

Elevation 

High 

Low 

High 

Low 

Low 

Ozone concentration 

1989 

129 

74 

100 

101 

103 

84 

80 

64 

ppb 

1988 

145 

97 

NA 

125 

146 

99 

101 

83 

a

 EPA Aerometric Information and Retrieval System network data. 

b

 Data provided by Appalachian Mountain Club and University of 

Massachusetts. 

c

 Data provided by Wiisconsin Department of Natural Resources 

(Florence County site). 

Table 2.—Mean annual SO, concentrations, 1982-858 

Class I area 

Great Gulf/Pres. Range-Dry River 

Lye Brook 

Dolly Sods/Otter Creek 

Rainbow Lake 

BWCAW 

Hercules Glades 

S02 

concentration 

ug/m3 

4.0 

7.3 

20.3 

2.4 

1.1 

3.0 

a

 Derived from Regional Atmospheric Deposition Model 

(RADM). 

BB 
P.8 

Sulfur and nitrogen deposition rates (Table 3) are shown for 

wet deposition (rain and snow), dry deposition, and droplet 

or cloud deposition. For wet deposition we used data from 

the National Atmospheric Deposition Network/National 

Trends Network (NADP/NTN) to estimate mean, volumeweighted S04-S, N03-N, and NH4-N concentrations in the 

rain and snow at each Class I area, then multiplied 

concentrations by mean annual precipitation amounts to 

estimate annual wet S and N deposition rates for each area. 

Table 3.—Estimated mean annual S and N deposition rates 

Class 1 

area 

Great Gulf/ 

Pres. RangeDry River 

Lye Brook 

Dolly Sods/ 

Otter Creek 

Rainbow Lake 

BWCAW 

Hercules Glades 

Elevat 

m 

High 

Low 

Mean 

High 

Low 

Mean 

High 

Low 

Mean 

Mean 

Mean 

Mean 

Sulfur deposition 

on Weta Dryb 

1750 10 

275 9 

850 11 

250 10 

1250 15 

575 13 

375 4 

550 3 

325 6 

2 

3 

3 

3 

6 

6 

2 

2 

3 

Coudc 

10 

-

3 

*" 

5 

— 

-

-

-

Total 

kn/ 

22 

11 

16 

17 

13 

14 

26 

19 

21 

6 

5 

9 

Nitrogen 

Weta Dry*1 

ha/hr— 

6 

5 

6 

5 

1,1. 

TO 

4 

3 

5 

3 

3 

3 

3 

4 

4 

3 

2 

3 

deposition 

Cloud0 Total 

6 15 

8 

11 

2 11 

a 

9 

4 m 

- 14 

16 

7 

5 

8 

a

 From NADP/NTN network data. Wet deposition rates are the products of mean annual 

precipitation amounts and mean S and N concentrations in precipitation. Mean 

concentrations were estimated from isopleth maps derived from mean volume-weighted 

concentrations at NADP sites. 

b

 Derived from Regional Atmospheric Deposition Model (RADM), provided by Robin Dennis, 

EPA, Research Triangle Park, NC. 

c

 Estimated from high-elevation deposition data from several Northeastern U.S. sites, as 

summarized by Lovett and Kinsman (1990). 

d

 Estimated from CORE/Satellite site data, as presented by Sisterson et al. (1990). 

Dry deposition of S and N occurs mostly as S02 and HN03 

gases. Estimates of dry S deposition were derived from the 

RADM model and provided by Robin Dennis. Measurements 

of dry N deposition at the eight CORE/Satellite sites indicate 

that dry N deposition is about 35 percent of wet plus dry N 

deposition in the Northeast, and about 45 percent of wet 

plus dry N deposition in the Midwest (Sisterson et al. 1990). 

We used these values to estimate dry N deposition on each 

Class I area. 

At high-elevation sites, concentrations of S04 , N03, and 

NH4 in cloud water are 5 to 20 times greater than in 

precipitation. Sites above about 1,000 m in elevation can 

receive as much S and N from cloud deposition as from 

wet deposition. We used deposition data from several highelevation sites in the Eastern United States, as summarized 

by Lovett and Kinsman (1990), to estimate cloud deposition 

on the high-elevation portions of the Class I wilderness 

areas in Vermont, New Hampshire, and West Virginia, 

locations for which there are no actual cloud deposition 

data. 

Average annual wet deposition has been changing over 

time. Emission of S02 in the Eastern United States 

has declined slightly over the past 15 years, and S04 

deposition, at least at the long-term study site at Hubbard 

Brook in New Hampshire, has decreased proportionally 

(Driscoll et al. 1989). Emission and deposition of N03 is 

constant or continues to increase. Forest managers need 

to be aware of the S04 decrease and of the years over 

which average values have been calculated. Year-to-year 

variation in deposition is large, so many years of record 

are needed before statistically significant trends can 

be detected. 
Terrestrial Ecosystems 

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Potentially Sensitive Components 

Sulfur can affect a terrestrial ecosystem in two ways: direct 

effects of S02 and indirect effects of total S loading. Sulfur 

dioxide may not affect the soils of an ecosystem but can 

have significant impacts on the health and vigor of some 

plant species. For example, aspen (Populus) exhibit leaf 

injury and reduced growth when exposed to S02 (Davis and 

Wilhour 1976). Total S loading includes all forms of S that 

enter an ecosystem: wet sulfate, dry sulfate, and S02. 

Sulfate forms of S may be detrimental to wilderness 

ecosystems by removing base cations from soils, causing 

changes in the soil solution and increasing the leaching of 

nutrients from the ecosystem. 

The leaching of calcium and other bases from soil exchange 

sites, which can result from elevated sulfur deposition, 

increases the acidity of the soil solution, decreasing the 

availability of nutrients for plant growth. The reduction in pH 

also will increase the concentration of aluminum in the soil 

solution, which can lead to aluminum toxicity. Aluminum 

toxicity effects may be intensified by low levels of calcium 

which can occur after long periods of high loadings of 

sulfate and nitrate. 

Nitrogen, unlike sulfur, is a growth-limiting nutrient in many 

forest ecosystems and does not accumulate in inorganic 

forms in the soil. It is rapidly incorporated into biological 

components of the ecosystem such as plants, animals, 

and microorganisms. Low levels of nitrogen deposition in 

wilderness areas may initially cause increased growth and 

vigor of the vegetation. However, as nitrogen loading 

continues, an imbalance of nutrients in the ecosystem may 

occur and the leaching of nitrate from the ecosystem may 

increase. An imbalance in nutrients could result in species 

replacement due to differences in nitrogen efficiencies and 

to changes in physiological processes such as dormancy 

initiation. Nitrogen deposition in excess of what the biological 

systems can utilize leads to nitrification and increased 

leaching of nitrate and associated cations. When a system 

reaches this point of nitrate leaching, it is considered 

nitrogen saturated. 

Ozone is not formed directly at point sources and thus is not 

a PSD increment pollutant. However, it should be evaluated 

in all permit applications as it is considered the most 

widespread and phytotoxic air pollutant. It is produced in 

the environment by the photochemical reaction between 

NOx and hydrocarbons, with the latter a "criteria" pollutant. 

Ambient ozone concentrations in some areas of the country 

are sufficiently high to cause visible injury, reduce 

photosynthesis and growth, and induce premature leaf 

senescence of many sensitive plant species. 

Examples of vegetation that may be sensitive to ozone or 

sulfur dioxide are listed in Tables 4 and 5. These are not 

exhaustive listings of all potentially sensitive species, nor 

are they lists of plants that always will be sensitive to air 

pollution. Rather, they can be used by managers to assess 

whether there is a likelihood of sensitive vegetation on the 

wilderness area. Little is known about the sensitivity to 

these two pollutants of rare and endemic plant species and 

understory and shrubby vegetation, and there is little 

information on the sensitivity of terrestrial invertebrate or 

vertebrate populations to these pollutants. 

Table 4.—Partial list of forest species sensitive to ozone and 

sulfur dioxide8 

Common name Scientific name 

SENSITIVE TO OZONE 

Green ash (Fraxinus pennsylvanica) 

White oak (Quercus alba) 

White pine (Pinus strobus) 

Jack pine (Pinus banksiana) 

Virginia pine (Pinus virginiana) 

Tulip-poplar (Liriodendron tulipifera) 

Black cherry (Prunus serotina)b-

c 

White ash (Fraxinus americana)0 

Milkweed (Asclepias sbriaca)b-

c 

Aster (Aster spp.)b 

Blueberry (Vaccinium spp.)c 

Elderberry (Sambucus canadensis^ 

SENSITIVE TO SULFUR DIOXIDE 

Bigtooth aspen 

Trembling aspen 

Yellow birch 

White pine 

Jack pine 

(Populus grandidentata) 

(Populus tremuloides) 

(Betula alleghaniensis) 

(Pinus strobus) 

(Pinus banksiana) 

a

 Excerpted from Davis and Wilhour (1976) unless otherwise 

indicated. 

b

 Based on observations of foliar symptoms in Class I wilderness 

areas in White Mountain National Forest and Green Mountain 

National Forest (Smith and Manning 1990). 

c

 Based on observation of foliar symptoms in Otter Creek and 

Dolly Sods wilderness areas, Monongahela National Forest 

(Jackson and Arbucci 1989). 
P.10 

Table 5.—Partial list of lichens sensitive to sulfur dioxide. 

The most sensitive species are present only below 40 ug/ 

m

3

 (average annual levels). The columns of numbers after 

the species names are the published limits of presence and 

absence in ug SO, /m3 

Species 

Bryoria furcellata 

Bryoria implexa 

Bryoria trichodes 

Caloplaca flavorubescens 

Catillaria griffithii 

Cetraria chlorophylla 

Cladonia bellidiflora 

Dimerella lutea 

Evernia divaricata 

Hypogymnia tubulosa 

Lecanactis abietina 

Lecidea nylanderi 

Lecidea vemalis 

Lobaria pulmonaria 

Ochrolechia pallescens 

Physcia semipinnata 

Ramalina americana 

Ramalina calicaris 

Ramalina fraxinea 

Rhinodina papillata 

Usnea filipendula 

Usnea florida 

Usnea variolosa 

Xanthoria candelaria 

Presence/absence 

13 to 26/26 to 52 

10 to 30/-

13 to 26/26 to 52 

30/35 

26/-

10 to 30/-

8/16 to 24 

30/-

10/-

10 to 30/-

10/-

13/13 to 26 

26/26 to 34 

26/26 to 34 

16 to 24/-

30/35 

13/13 to 26 

30/35 

30/35 

13/13 to 26 

10 to 30/-

30/-

26/-

16 to 24/-

Reference 

3 

6 

3 

1,6 

2 

6 

8 

1 

6 

6,8 

6 

3 

4 

1,4,5,6 

8 

1 

3 

1,6*,7 

3 

6 

1 

2 

8 

1. Hawksworth and Rose 1970. 

2. LeBlanc 1969. 

3. LeBlanc etal. 1972. 

4. LeBlanc etal. 1974. 

5. Nash 1976. 

6. Trass 1973. 

7. Hawksworth and Rose 1976. 

8. Johnson 1979. 

In general, sites that are the most sensitive to increased 

sulfur loading are those most likely to exhibit effects of 

increased levels of sulfur on soils: leaching of bases, drop 

in pH, and increased Al solubility. These might include sites 

with shallow soils or those with soils with low base saturation. 

Soils developed from outwash sands or sandstone 

weathering, coarse soils over bedrock, etc. probably are the 

most susceptible. Soils derived from limestone,.such as 

those found in the Hercules Glades Wilderness Area, are 

not likely to be susceptible to the effects of increased 

deposition. Soil acidification is discussed in greater detail in 

the section on aquatic ecosystems. 

Wilderness soils that already are N-saturated or are 

severely N-limited may be sensitive to increased nitrogen 

loading. One example of a nitrogen-saturated community is 

the high-elevation spruce-fir forests in the southern 

Appalachians. Also at risk are old-growth communities that 

use small amounts of nitrogen or recycle large amounts in 

litterfall. Shallow soils or soil of low base saturation may be 

susceptible to change (cation leaching, acidification, 

mobilization of metal ions) with increased N loading. 

However, deep soils with high base saturation will be 

affected by N leaching only after long periods. 

Another scenario in which additional nitrogen could have an 

effect entails nitrogen acting as a fertilizer: this can be a 

negative or a positive effect. These impacts cannot be 

assessed over the short term. For example, if a particular 

plant association is found only on infertile sites, continuous 

additions of nitrogen could change that association or 

eliminate it by creating an environment where other plants 

can compete more successfully than the original species. 

Rare and endemic plants often are found on such unique 

sites. Thus, the manager should take a careful look at 

communities that currently are found only on nutrientpoor sites. 

Relationship of Sensitive Components to AQRVs 

The AQRVs describing terrestrial components of the 

wilderness areas are written to cover broad characteristics 

such as vegetation. These broad characteristics must be 

divided into smaller components, such as the particular 

species of trees, plants, and lichens, so that the sensitive 

components can be identified and documented. Many of the 

sensitive components described in the previous section may 

not be important components of the AQRVs for a particular 

wilderness area. It is important that each wilderness area be 

considered on a separate basis by the FLM. It also is 

important for the FLM to evaluate both terrestrial and 

aquatic systems as sensitivity will vary, as reflected in red 

and green line values. Assessments should incorporate the 

most sensitive components. 
P.11 

Green Line and Red Line Values 

Screening criteria (Table 6) should be applied on a case-bycase basis, using air quality snd meterological conditions 

from each wilderness where available. However, because 

the available information on air quality and ecosystem 

components is limited, the same green and red line values 

have been selected for all eight Eastern Region Class I 

areas. Obvious exceptions are pointed out. 

Table 6.—Terrestrial green and red screening values 

Pollutant Green line Red line 

SULFUR DEPOSITION 

S02 (annual mean) < 5 ug/m3 > 40 ug/m3 

(3-hr max. mean) < 100 ug/m3 > 200 ug/m3 

Total (all forms of sulfur) 5 to 7 kg/ha/yr > 20 kg/ha/yr 

NITROGEN DEPOSITION 

Total nitrogen 5 to 8 kg/ha/yr > 20 kg/ha/yr 

OZONE 

Growing season, second 

highest 1 hr average ^ 80 ppb > 120 ppb 

The total deposition or exposure values are compared with 

the green-line/red-line model to determine the appropriate 

course of action. Green line values were set at levels at 

which it was reasonably certain that no significant change 

would be observed in ecosystems that contain large 

numbers of sensitive components. Conversely, red line 

values were selected at levels at which it was reasonably 

certain that a significant change would occur in both the 

sensitive and tolerant components of the ecosystem. 

Limited foliage injury or symptom development can occur 

on sensitive species at the selected green line values for 

ozone and S02 . However, the significance to the wilderness 

ecosystem of this foliage injury may be minor. Studies have 

demonstrated that plants with foliage exhibiting air pollutant 

damage symptoms can continue to grow at competitive 

rates. Thus, the relationship of foliar injury to the AQRVs of 

a particular wilderness will determine the significance of 

such symptom development. Additionally, green line levels 

were not selected to assure the protection of the most 

sensitive genetic material in the ecosystem. This approach 

was taken because the AQRVs were established to protect 

the current ecosystem, which would be expected to 

continue even if part of the genetic material of one or more 

species was lost. If the AQRVs are revised at a later date to 

include sensitive genetic material, the green line values 

may need to be lowered. 

The green line (3-hr maximum peak) S02 value of 100 ug/m3 

(or long-term average of 5 ug/m3) was selected because no 

significant large-scale visible injury or physiological impacts 

are expected on any species in the ecosystem below these 

levels, based on published literature. The red line values 

(3-hr maximum peak value of 200 ug/m3 or 40 ug/m3 yearly 

average) were selected because similar levels have been 

demonstrated to be harmful to many of the species found in 

the wilderness areas in Region 9. However, the effect of 

S02 on vegetation will vary with several parameters, 

including the concentration, duration, and frequency of 

peaks in the growing season. 

The green line value for total S loading is 5 to 7 kg/ha/yr. 

This is approximately the loading in Boundary Waters 

Canoe Area and Rainbow Lakes Wilderness Area; to date, 

no adverse effects have been observed in these areas, so 

the group believed that this value represents the lowest 

level at which we can estimate no effects. However, aquatic 

systems may be more sensitive and cumulative effects 

should be considered, particularly for watersheds 

approaching their sulfate adsorption capacity, as in Dolly 

Sods and Otter Creek wilderness areas (See discussion on 

aquatic ecosystems). 

The red line value of 20 kg/ha/yr may be expected to cause 

cation leaching from most of the wilderness soils in Region 

9. Supporting this observation is the calculation that soil 30 

cm deep with a bulk density of 1.1 kg/L receiving a sulfur 

loading of 20 kg/ha/yr could achieve a reduction of 1 meq in 

base cations within about 2.6 yr (Fox et al. 1989). However, 

the loss might be less if the soil contained more free 

calcium carbonate, as is the case for the Hercules Glades 

Wilderness, or if the sulfur absorbing capacity of the soil 

is high. 

For N, a green line of 5 to 8 kg/ha/yr was selected because 

these are the levels that are currently deposited in the more 

"pristine" wilderness areas of Region 9 (BWCAW, Rainbow 

Lake, Hercules Glades). To date, the decline of red spruce 

at high elevations is the only significant change in 

ecosystem structure or function that might result from 

increased N or S deposition. The red line value of 20 

kg/ha/yr of total nitrogen was selected because most, if not 

all, of the wilderness soils will leach nitrate and associated 

base cations if this level of N input is maintained. 

Ozone, like S02, exists in the environment as a gas and its 

impact on vegetation depends on many variables, including 

concentration, duration, frequency of peaks and 

environmental conditions such as temperature and 

humidity. The ozone values given in Table 6 represent the 

second highest 1-hr average in the growing season. This 

value is reasonably well correlated with plant response, 

though research is currently under way to improve on this 

variable by including some influence of accumulated 

effects. It is recommended that some type of cumulative 

index that weights the high concentrations more than the 

lower concentrations be developed as soon as possible. 

8 
P.12 

The green line value for ozone for all wilderness ecosystems 

was set at 80 ppb (second highest 1-hr mean). No significant 

change is expected in the ecosystem if ozone remains 

below this level. However, on the basis of available 

information, it is reasonable to conclude that some symptom 

development or leaf senescence may be expected even at 

this low level. The red line value was set at 120 ppb (second 

highest 1-hr mean). At this level, ozone will reduce plant 

growth and the competitive ability of many species. 

Sensitive species may be eliminated from the ecosystem. 

In addition to short-term ozone effects being important, the 

effect of ozone is cumulative for each individual in the 

ecosystem. A plant weakened by ozone in one season is in 

a poorer competitive position at the beginning of the second 

season than a nonsensitive plant. After two or more seasons 

it is weakened even further until it may be eliminated. The 

PSD recommendations will depend on the relative 

importance of the different plant species in the plant 

community as an AQRV within each wilderness. 

Aquatic Ecosystems 

Potentially Sensitive Components 

The ability of a lake or stream to buffer incoming acids, i.e., 

its acid-neutralizing capacity (ANC) or alkalinity, depends 

primarily on the emount of bicarbonate (HCO3) in the water 

and the rate at which it is supplied from the watershed^. 

Bicarbonate supply depends on watershed geology and 

hydrology. In the watershed, HC03 is produced by the 

reactions of water and carbon dioxide (or acids from 

atmospheric deposition) with carbonate minerals such as 

calcite and dolomite, and cation aluminum silicate minerals 

like feldspars and micas. These weathering reactions 

release HC03 into solution, accompanied by approximately 

equal amounts (on an equivalent weight or ueq/L basis) of 

base cations—calcium (Ca), magnesium (Mg), sodium (Na), 

and potassium (K) (Stumm and Morgan 1981). How much 

HC03 and other mineral-weathering products actually reach 

a lake or stream depends on the flow paths of water through 

the watershed. Water that moves rapidly over the land 

surface or along shallow subsurface pathways usually 

contains much less dissolved material than water that takes 

a slow, deep route to a lake or stream. Ground water is 

typically high in dissolved ions. Lakes and streams with 

strong ground water inputs usually have high buffering 

capacities. 

In addition to alkalinity supplied by the mineral weathering 

in the watershed, some alkalinity is generated by in-lake 

processes of S04 and N03 reduction and by ion exchange 

with the bottom sediments of lakes. This can be a 

significant source of ANC in lakes with only minimal inputs 

of HC03. In-lake alkalinity production is a much more 

significant source of ANC in lakes that have long hydrologic 

flushing times, several years, than in lakes that flush more 

frequently. In peatlands, the retention of S04 and its 

reduction to sulfides and organic forms as well as the 

reduction of N03 to N gasses by denitrification also are 

significant ANC-producing processes (Turner et al. 1989). 

When a sensitive lake is subjected to acid loading, either 

falling directly on the lake as precipitation and dry 

deposition or flowing in from the surrounding watershed, 

incoming acids are neutralized by HC03, which is 

consumed in the process. If HC03 is consumed faster than 

it is supplied by mineral weathering in the watershed and by 

in-lake processes, then ANC eventually falls to zero and the 

lake becomes acidic. 

Baker et al. (1989) found that S04 is the dominant acidic 

anion in surface waters. At present, N03 generally 

contributes little acidity to lakes in the United States. Nitrate 

may be a significant source of acidity in some streams, 

especially during episodic flow events resulting from rain 

storms and snowmelt. Organic anions are an important 

source of acidity in many lakes associated with peatlands, 

especially in the upper Midwest. 

Concentrations of S04 in surface waters are typically very 

low where deposition is low, and increase in a nearly linear 

fashion as deposition increases (Sullivan et al. 1988; Baker 

et al. 1989). Brakke et al. (1989) estimated background, preindustrial S04 levels in lakes with low base cation 

concentrations in the Eastern United States to be about 10 

to 15 ueq/L. While surface water S04 generally increases 

with deposition, there is considerable variation in this 

relationship due to differences in the supply of S04 from 

natural geologic sources, as well as differences in the 

amounts of S04 retained by the watershed by soil 

adsorption, reduction, and other processes. 

•* 

Sulfate can be retained in the soil by adsorption to hydrous 

oxides of iron (Fe) and aluminum (Al) and the edges of 1:1 

clay mineral particles (Bohn et al. 1986). Highly weathered 

soils normally contain considerable quantities of Fe and Al 

hydrous oxides and 1:1 clays and have high capacities to 

adsorb S04. Lakes and streams in the Southeastern United 

States contain low amounts of S04 relative to S04 

deposition. Much of the S04 that falls on these watersheds 

apparently is absorbed by the old, highly weathered soils of 

the region and does not reach surface waters, at least at 

present. In the future, less S04 will likely be retained by the 

soil as S04 adsorption sites become saturated. In the 

Northeast and Midwest, relatively little S04 is retained by 

the soil. 

In contrast to S04, N03 is taken up rapidly by aquatic and 

terrestrial biota and thus does not appear to promote lake 

acidification in most cases. At present, essentially all of the 

N deposited from atmospheric sources in watersheds of 

lakes in the Northeast and Midwest appears to be retained 

by the terrestrial portions of the watersheds or utilized by 

the aquatic biota (Baker et al. 1989). One exception is a 

group of lakes in the Adirondack Mountains in New York 

where N03 contributes up to 17 percent of the strong acid 

anions and appears to be associated with short-term 

variation in pH and aluminum (Henriksen and Brakke 1988). 

Terrestrial ecosystems that have received high levels of N 

deposition for many years may become N saturated and 

export significant amounts of N03. Henriksen and Brakke 

(1988) estimated the "nitrate mobility factor" (NF) for lakes 

in Norway. This factor, defined as the ratio of N03 to S04 
P.13 

in runoff from a watershed divided by the ratio in total N03 

and S04 inputs to the watershed, expresses the mobility of 

N03 (and thus its contribution to lake acidification) as a 

fraction of the mobility of S04. Mean values of NF for 

individual counties in Norway ranged from 0.05 to 0.54, and 

increased with N03 deposition rate and amount of runoff. 

While lakes in the Northeast and Midwest generally appear 

to be little affected by N deposition, the same may not be 

true for some streams. Baker et al. (1989) showed an 

approximately linear relationship between wet N deposition 

and N03 in streams in the Eastern United States, but the 

effect of N deposition on streams appears to be small, 

compared to that of S04. Stream N03 concentrations are 

only 10 to 30 percent of S04 concentrations at the same 

wet S snd wet N deposition rates. 

Increased amounts of S04 (and in some cases NOg) anions 

from atmospheric deposition, moving through the soil and 

entering surface waters, must be accompanied by 

equivalent amounts of cations. In soils in which about 15 

percent or more of the negative exchange sites are 

occupied by base cations, Ca, Mg, K, and Na, much of the 

increase in solution cation concentration will consist of 

these base cations. However, in low base-saturated soils 

(less than 15 percent), due to a complex series of processes 

involving the presence of high partial pressures of C02 gas 

in soil, the equilibrium among carbonic acid, H, and HC03, 

and the reaction of H cations with the soil exchange sites, 

much of the increased cation load in soil solution and in 

discharge water to lakes and streams will be made up of H 

and Al species (Reuss and Johnson 1985). These hydrogen 

ions have an acidifying effect on surface waters. Dissolved 

Al is toxic to fish and other aquatic organisms. For example, 

dissolved Al in excess of 200 ug/L is toxic to brook trout 

(Schofield and Trojnar 1980; Baker and Schofield 1982). 

that are unaffected by acid deposition and that do not 

contain large amounts of organic anions. Atmospheric 

deposition increases S04 (and in some cases NOg) in 

surface waters. To maintain the charge balance between 

cations and anions in solution, an acid deposition-induced 

increase in surface water S04 (and NOg) must be 

accompanied by an increase in cations due to increased 

mineral weathering and cation leaching, and/or by a 

decrease in ANC. In very acid waters, an increase in Al 

cations may occur in place of a loss of ANC. 

Henriksen (1984) defined a useful factor, F, for describing 

the response of surface water chemistry to acidic 

deposition. The value of F relates the increase in the 

concentration of base cations in surface water to the 

increase in S04 resulting from S04 deposition: 

F = change in base cations/change in S04 

The value of F ranges from 0 to 1. If F = 1, base cations 

increase with S04 in response to acid deposition while 

surface water ANC is unchanged. If F = 0, surface water 

ANC decreases as S04 increases while the concentration of 

base cations remains constant. In waters in which N03 

deposition contributes to acidification, F should be 

considered in terms of the change in the surface water 

concentration of S04 + N03. The value of F for a particular 

lake or stream is determined by the characteristics of the 

individual watershed. In areas of readily weatherable 

calcareous bedrock and soils, F approaches 1. For very 

dilute lakes snd streams, F approaches 0 as hydraulic 

residence times in soils, mineral weathering rates, and soil 

base saturation decrease (Brakke et al. 1990). 

Brakke et al. (1990) developed a method to estimate F for 

individual lakes from base cation concentrations: 

Acidic soil water may percolate deep into the soil rather 

than flowing directly into a lake or stream. If this water 

comes in contact with weatherable, base cation-containing 

minerals in the subsoil or the underlying bedrock, it may be 

neutralized before reaching surface waters. During base 

flow conditions, the water flowing in streams typically comes 

from relatively deep soil water or ground water. During 

snowmelt or following large storms, however, streamflow 

often is dominated by shallow soil water. In areas impacted 

by heavy atmospheric acid loadings, sensitive streams with 

neutral or slightly alkaline pH's during base flow may have 

severely depressed pH's and toxic levels of dissolved 

aluminum during episodic snowmelt and stormflow events 

due to the flush of acidic Al-laden soil water into the 

streams (Swistock et al. 1989). These episodes may have 

detrimental impacts on stream fisheries (Gunn and Keller 

1984; Gagen snd Sharpe 1987). Similar episodes of pH 

depression and elevated Al levels also have been seen in 

lakes during snowmelt in regions of high acid deposition. 

Because approximately equal amounts of base cations and 

HC03 are released by weathering of carbonate and 

aluminum silicate minerals, the ratio between ANC and 

base cations is typically close to 1:1 in lakes and streams 

F = sin(90 BC*/S), 

where BC* = the sum of non-marine base cations in the 

lake and S = the value of BC* at which F = 1. Data from 

lakes in southern Norway indicate that the value of S is 

between about 200 and 400 ueq/L. Brakke et al. (1990) 

estimate that F is about 0.2 to 0.4 for dilute lakes in the 

Western United States and 0.4 to 0.7 for acidic lakes in the 

Adirondacks. 

In a review of biological effects of surface water 

acidification, Baker et al. (1990) concluded that the 

chemical constituents most influencing the biota are pH, 

inorganic monomeric (non-polymerized) aluminum, and Ca, 

with surface water pH being the single most important 

parameter. Fish or other aquatic organisms appear to be 

little affected so long as the pH remains at 6.5 or higher; 

however, noticeable adverse effects begin to occur as pH 

declines to about 6.0. The most acid-sensitive fish species, 

such as the fathead minnow (Pimephales promelas), 

experience reproductive failure at pH's near 6.0. Some 

important food organisms such as the opossum shrimp 

(Mysis relicta) disappear at pH's slightly below 6.0. Between 

pH 6.0 and 5.5, many species of zooplankton, mayflies, 

10 
P.14 

mollusks, minnows, and game fish are adversely affected. 

In general, fish eggs snd fry are more sensitive to acidity 

than adult fish, and fish populations succumb to 

reproductive failures at pH's above which adult fish can 

survive. In lakes where the average pH is below 5.0, most 

fish species, nearly all mollusks, and many other groups of 

bottom-dwelling organisms are eliminated, the food web is 

severely disrupted, and mats of algae frequently cover lake 

bottoms (Magnuson et al. 1984). 

In studying the relationship between pH and the distribution 

of fish species in 138 lakes in Wisconsin, Rahel and 

Magnuson (1983) found that several species of minnows 

(Cyprinidae) and darters (Etheostoma spp.) were absent at 

pH's below 6.0. Black crappie (Pomoxis nigromaculatus), 

muskellunge (Esox masquinongy), smallmouth bass 

(Micropterus dolomieui), walleye (Stizostedion vitreum). and 

northern pike (Esox lucius) were absent at pH's below 5.5. A 

few species such as the bluegill (Lepomis macrochlrus) and 

yellow perch (Perca flavescens) survive and reproduce 

successfully at pH 4.5. In an artificially acidified Canadian 

lake, reproductive failure in fathead minnow occurred below 

about pH 6.0, in lake trout (Salvelinus namaycush) below 

about pH 5.6, and in white sucker (Catostomus commersoni) 

below about pH 5.0 (Schindler et al. 1985). Brook trout 

(Salvelinus fontinalis) cannot survive at pH levels below 4.8 

to 5.2 (Baker et al. 1990). 

Aluminum solubility increases rapidly as pH decreases 

below about 6.0 (Hem 1985), but the chemistry of Al is 

complex and, consequently, its toxic effects on the biota are 

highly variable. Some Al in surface waters is bound to 

organic molecules and is relatively nontoxic (Baker et al. 

1990). This can be an important factor in waters colored by 

drainage from wetlands. Above about pH 4.5, dissolved 

monomeric Al ions tend to polymerize (Hem 1985). In 

general, the inorganic monomeric fraction is considered the 

toxic component. Concentrations of inorganic monomeric Al 

above 10 to 50 ug/L cause adverse biological effects (Baker 

et al. 1990). Dissolved Al (monomeric plus polymeric) in 

excess of 200 ug/L has been found to be toxic to brook trout 

(Schofield and Trojnar 1980; Baker and Schofield 1982). 

Aquatic organisms can generally tolerate higher Al 

concentrations and lower pH's in waters that contain higher 

concentrations of Ca. At Ca concentrations below 100 to 

150 ueq/L, small changes in Al can be important (Baker et 

al. 1990). 

Green Line and Red Line Values 

Selection of green and red line values for aquatic AQRVs 

was a two-step process. First, we determined the surface 

water ANC value above which normal healthy aquatic biota 

would be present and aquatic ecosystems would be unlikely 

to be adversely affected—the green line ANC value, and the 

ANC below which aquatic ecosystems would Jjkely be 

adversely affected—the red line ANC value. We selected 

green and red line ANC values that we believed were 

indicative of the overall health of aquatic ecosystems and 

were applicable to all eight Class i wilderness areas. 

The second step was to estimate the green and red line 

deposition rates of S and N for each Class I area. The green 

line deposition rates are the rates of total S and N 

deposition at which we estimated that the ANC of the most 

sensitive lake or stream in each Class I area would remain 

above the green line value. The red line deposition rates for 

each Class I area are those total S and N deposition rates 

at which we estimated the most sensitive lake or stream 

would have an ANC below the red line value. 

We selected 25 ueq/L as the green line ANC value. Twentyfive ueq/L is about the lower limit of the range of ANC 

values over which the land manager can be reasonably 

certain that fish and other aquatic organisms will be 

unaffected by low pH. As Figure 2 shows, essentially all 

clear lakes (color less than 25 Pt-Co units) with ANC's of 25 

ueq/L or more have air-equilibrated pH's of at least 6.5. 

These lakes should have a normal, healthy biota. Because 

of inputs of organic acids from peatlands or other wetlands, 

some moderately colored lakes (color between 25 and 75) 

with ANC's of from 25 to 50 ueq/L have pH's between 6.5 

and 6.0. While marginal, these lakes should still have 

essentially normal fauna and flora populations. A few highly 

colored lakes (color greater than 75) in this ANC range have 

pH's as low as 5.5; some of the most acid-sensitive species 

probably would be absent from these lakes. 

Below 25 ueq/L of ANC, surface water pH's drop sharply. 

Small losses of ANC result in relatively large decreases in 

pH. Below an ANC of 10 ueq/L, air-equilibrated pH's fall into 

the range in which chronic adverse biological effects can be 

anticipated (Fig. 2). We selected 10 ueq/L as the red line 

value ANC value for chronic or long-term effects. This is a 

more conservative red line ANC value than the -5 ueq/L red 

line that was used in the original screening process 

(Fox etal. 1989). 

11 

* 
P.15 

CL 

ANC, /zeq/l 

50 -40 -30 -20 -10 0 10 20 30 40 50 

-<—I—'—I—'—I—•—I—i—I—i—l—'—I—•—I—•—I—• -

7.5 

7.0 

6.5 

X 6.0 

CL 

5.5 

5.0 

4.5 

T 4.0 

LAKE COLOR, Co-Pt UNITS 

° 25 OR LESS 

* 25 TO 75 

* 75 OR MORE 

O O _ 4 A 

0 0 , 

•<PRA *°O°5>*° T •t 

„ o . 

O o ' ' 

° All®*"" ^ ' ** A ' 

A o<? ** * 

V T 

O ^ * T 

9.0 

8.5 

8.0 

7.5 

7.0 

6.5 

6.0 

5.5 

5.0 

4.5 

4.0 

3.5-I—'—I—•—I—*• 

LAKE COLOR, Co-Pt UNITS 

o 25 OR LESS 

* 25 TO 75 

* 75 OR MORE 

H 1 1- H 1 1- H 1 r-

-100 -50 0 50 100 150 200 250 300 350 400 

ANC, fieq/\ 

Figure 2.—Relationship of ANC and pH in 2,117 lakes in the Eastern and Western United States (data from Kanciruk et al. 

1986 and Eilers etal. 1987). 

12 
P.16 

In aquatic ecosystems that are adapted to natural episodic 

pH depressions, ANC and pH can probably fall below the 

chronic red line value for short periods without significant 

injury to the biota. For example, episodes with pH's below 

5.0, ANC's below zero, and elevated Al concentrations for 2 

to 5 days may be required before brook trout are adversely 

affected (Baker et al. 1990). In their review of episodic 

acidification of surface waters, Wigington et al. (1989) 

classified an episode as likely to impact aquatic biota if the 

pH minimum is 5.0 or less and the ANC falls below zero. 

We selected 0 ueq/L as the episodic red line ANC value. 

To estimate the green and red line rates of total S 

deposition, i.e., the deposition rates that will result in green 

and red line ANC values for each wilderness area, we used 

available water-quality data, our best estimates of 

deposition rates, and empirical relationships between S 

deposition and concentrations of S04 , base cations, and 

ANC in lake and stream water. While our estimates seem 

reasonable, we recommend that the green and red line 

deposition rates presented here be used as interim values 

until additional data can be collected and a more thorough 

analysis can be undertaken. This effort should involve 

comparisons of the results of multiple techniques such as 

other empirical models, simulations using models like 

MAGIC (Modelling the Acidification of Groundwater in 

Catchments; Cosby et al. 1985a,b) and ILWAS (Integrated 

Lakes-Watershed Acidification Study; Gherini et al. 1985), 

and paleolimnological studies (see section on research 

needs). 

One concern is that empirical relationships such as those 

used here imply that surface water chemistry is currently in 

equilibrium with deposition. However, MAGIC simulations of 

water chemistry in Norway and the Eastern United States 

project that if deposition continues at its present rate or 

even decreases slightly (5 percent), sensitive lakes and 

streams will continue to acidify (Cosby et al. 1989; Sullivan 

etal. 1991). 

On the basis of the relationship between N deposition and 

N03 concentrations in streams shown by Baker et al. (1989) 

and the N03 mobility factors for Norwegian lakes and 

streams estimated by Henriksen and Brakke (1988), we 

estimate that a given deposition rate of N has 20 percent of 

the acidification effect of the same rate of S deposition. The 

acidifying effects of N on surface waters cannot be 

considered separately from the effects of S, but at present 

and at the current deposition rates, S appears to be much 

more effective than N as an acidifying agent for surface 

waters in the United States. Therefore, we have estimated 

green and red line deposition rates for S alone and for S + 

20 percent of N, but not for N alone. Again, these should be 

regarded as interim values until the effects of N deposition 

on each Class I area can be assessed more accurately. 

Specific determinations were made for each wilderness 

area and are discussed in five sections (New Hampshire 

and Vermont, West Virginia, Wisconsin, Minnesota, and 

Missouri). 

New Hampshire and Vermont: Presidential RangeDry River, Great Gulf, and Lye Brook Wildernesses 

Chemistry data from lakes and streams in and adjacent to 

these wilderness areas show that these waters are acidic 

and very sensitive to further acidification by atmospheric 

deposition. Base cation concentrations range from about 75 

to about 150 ueq/L. ANC's range from abouflO ueq/L to 

less than zero, and pH's run from the low 4's to the high 

5's. The pH's of waters with base cations in the 120 to 150 

ueq/L range, mostly stream reaches at the lower and middle 

elevations, generally run from about 5.1 to 5.5. Waters with 

base cation concentrations below 100 ueq/L, mostly higher 

elevation lakes, have pH's from 4.4 to 4.8. 

The most complete chemistry data set for any of the 

streams and ponds in the Presidential Range-Dry 

River/Great Gulf area is from Gibbs Brook, which originates 

a few hundred yards to the west of the Presidential 

Range/Dry River Wilderness boundary. The Gibbs Brook 

watershed is similar geologically and topographically to the 

Presidential Range-Dry River and Great Gulf Wilderness 

Areas, and the chemistry of Gibbs Brook should be 

representative of water chemistry conditions in the 

Wildernesses. The pH of Gibbs Brook ranges from about 

5.1 and 5.4 during base flow conditions. ANC is only 

occasionally above zero. During high flows from snowmelt 

and storms, the pH falls to between 4.5 and 5.0. Base 

cation concentration is about 120 ueq/L. Sulfate averages 

about 100 ueq/L. Chloride (Cl) is low, less than 10 ueq/L. 

Most of the available water chemistry data for the Lye Brook 

Wilderness are from Bourn Pond. Bourn Pond is chemically 

similar to Gibbs Brook; its pH ranges from about 4.8 to 5.5, 

with an average of about 5.2. ANC is typically in the -5 to 

+ 5 ueq/L range. The pH and ANC generally are lowest in 

the spring and early summer. Base cations average about 

110 ueq/L, S04 about 100 ueq/L, and Cl about 10 ueq/L. 

These data are indicative of surface waters that have been 

significantly impacted by acidic deposition. Marine sources 

of S04 and other ions appear to be small, as evidenced by 

the low Cl content of the waters. If we assume an average 

background (preindustrial) concentration of S04 in the 

surface water of about 15 ueq/L (Brakke et al. 1989), an 

organic anion concentration of about 10 ueq/L, and a cation 

enrichment factor (F) of 0.5 to 0.6 (see Brakke et al. 1990), 

then we estimate that Bourn Pond, Gibbs Brook, and the 

other ponds and streams in these areas have suffered an 

ANC loss of about 35 to 40 ueq/L due to acidic deposition. 

Acidification of lakes in the Adirondack Mountains in New 

York has been estimated by use of the MAGIC model. The 

median change in ANC for the Adirondack lakes since 

preindustrial times was estimated to be -46 ueq/L (Sullivan 

et al. 1991). This compares well with the ANC losses 

estimated here for the surface waters of the Presidential 

Range-Dry River/Great Gulf and Lye Brook areas. 

Paleolimnological studies of diatoms in Adirondack lake 

sediments, however, suggest a somewhat smaller loss of 

ANC (Sullivan et al. 1991). 

13 
P.17 

Many of the streams in these three wilderness areas contain 

populations of brook trout, typically at the lower and middle 

elevations. These populations are still viable but probably 

are stressed by the acidic conditions of the streams snd the 

loss of ANC. At higher elevations, in the headwaters of 

these streams are several small ponds that are too acidic to 

support permanent trout populations. Some of these, such 

as Bourn Pond, are thought to have supported permanent 

populations of brook trout in the past. In a survey of fish 

populations, Langdon (1984) found only two species of fish 

in Bourn Pond—brown bullhead (Ictalurus nebulosus), a 

highly acid-tolerant species, and brook trout, which is 

regularly supplemented by stocking. Fiske (1987) found a 

scarcity of acid-sensitive macroinvertibrate species in Bourn 

Pond. Langdon (1984) related the low number of fish 

species in Bourn Pond and other sensitive southern 

Vermont lakes to low pH and high Al concentrations. 

Present total S and N deposition rates are estimated to be 

about 14 to 16 and 9 to 11 kg/ha/yr, respectively, in the 

Great Gulf/Presidential Range-Dry River and Lye Brook 

Wildernesses (Table 3). The ANC's and pH's of the ponds 

and streams in these areas currently are at or below both 

the chronic and episodic red line values. The existing brook 

trout and other aquatic organisms are likely to be 

experiencing stress and damage; additional deposition will 

cause additional damage. Some higher elevation 

populations may already have been destroyed. Therefore, 

we believe that the present S and N deposition rates for 

these wilderness areas are at or even above the red line 

values. We estimate the red line total S deposition rate to 

be 14 to 16 kg/ha/yr, and the red line S + 20 percent of N 

to be 16 to 18 kg/ha/yr. 

To achieve the green line ANC value of 25 ueq/L, most of 

the surface waters in the Great Gulf/Presidential Range-Dry 

River and Lye Brook Wildernesses would have to increase 

in ANC by 15 to 25 ueq/L, which would require a substantial 

reduction in deposition. Galloway et al. (1984,1987) has 

estimated the background (preindustrial) concentration of 

S04 in precipitation to be 5 to 7 ueq/L. Given 1,200 to 1,600 

mm of annual precipitation, we estimate background S 

deposition (wet plus dry) in the Great Gulf/Presidential 

Range-Dry River and Lye Brook Wildernesses to have been 

1.5 to 2 kg/ha/yr. We estimate surface water S04 to have 

increased by about 85 ueq/L over background. This is an 

increase in S04 of about 6 to 7 ueq/L for each 1 kg/ha/yr of 

S deposition. If we assume that surface water S04 will 

decrease at this same rate in response to a decrease in S 

deposition, and that ANC will increase at 40 to 50 percent of 

the rate of S04 decrease (i.e., F = 0.5 to 0.6), then a' 

decrease in S deposition to about 6 to 8 kg/ha/yr will be 

necessary to achieve green line ANC values. This is similar 

to the 3 ueq/L ANC increase for each 1 kg/ha/yr decrease in 

S deposition projected for Adirondack lakes by the MAGIC 

model (Sullivan et al. 1991). Thus, we estimate the green 

line total S deposition rate to be 6 to 8 kg/ha/yr and the 

green line S + 20 percent of N deposition rate to be 7 to 9 

kg/ha/yr. 

West Virginia: Dolly Sods and Otter Creek 

Wildernesses 

The bedrock of the Dolly Sods and Otter Creek 

Wildernesses consists of the Pennsylvanian age 

Conemaugh Group, Allegheny Formation, and Pottsville 

Group, underlain by the Mississippian age Mauch Chunk 

Group and Greenbrier Group (Cardwell et al. 1986). These 

are sedimentary materials—beds of sandstone, siltstone, 

shale, conglomerate, and some limestone. The 

Pennsylvanian strata also contain numerous coal beds. 

Limestone is more prevalent in the Mississippian groups; 

the Greenbrier is predominately limestone. 

The ability of the streams in these wilderness areas to 

sustain populations of fish and other aquatic organisms is 

closely related to bedrock geology. Streams that arise in 

and flow through the Lower Pennsylvanian materials tend to 

be too acidic to support fish. Streams influenced by the 

Mississippian rocks tend to be more suitable for aquatic life. 

Similar geology extends northward into Pennsylvania. 

Studies in the Laurel Hill area of southwestern 

Pennsylvania, about 120 km north of the Otter Creek and 

Dolly Sods Wildernesses, showed that water from springs 

and seeps emanating from Allegheny and Pottsville strata 

had ANC's close to zero and pH's in the 4's. In contrast, 

water from the Mauch Chunk had ANC's of about 100 ueq/L 

and pH's in the 6's (Dinicola 1982; Sharpe et al. 1984). 

Some of the Allegheny and Pottsville strata contain pyrite 

(FeS2) that produces S04 and acid as it oxidizes. Pyritic 

materials appear to be a source of natural acidity in many of 

the tributary streams in the Otter Creek and Red Creek 

systems. 

In addition to natural sources of acidity, the streams in the 

Dolly Sods and Otter Creek Wildernesses receive a large 

acid load from atmospheric deposition. We estimate the 

mean annual total deposition rate of S and N to be about 21 

and 16 kg/ha (Table 3), the highest among all the Class I 

wilderness areas in the Eastern Region. At present, the 

soils of the Dolly Sods/Otter Creek area appear to be 

retaining by adsorption 40 to 50 percent of the S04 

deposited from the atmosphere based on research on an 

adjacent watershed (Helvey and Kunkle 1986). This 

retention of S04 provides to the streams some level of 

protection from the full effects of S04 deposition. 

Eventually, the S04 adsorption capacity of the soils will be 

saturated, and this protection will be lost. Decreases in the 

capacity of the soil to adsorb sulfate and resultant increases 

in stream water sulfate concentrations have been 

documented in recent years in some North Carolina streams 

(Wayne Swank, USDA Forest Service, Southeastern Forest 

Experiment Station, Coweeta Hydrologic Laboratory, pers. 

commun.). 

Otter Creek, the main stream in the Otter Creek Wilderness, 

and Red Creek, which drains the Dolly Sods Wilderness, 

have many similarities. Both streams have some wetland 

acreage in their headwaters, particularly Red Creek, which 

has broad gentle slopes over much of the upper watershed. 

In these headwater areas, both streams are sensitive to 

acidification, but are still capable of supporting some fish 

14 
P.18 

species. During normal flow conditions, the pH in much of 

the Red Creek headwaters may typically be in the 6's, but 

the Left Fork is more acid and may be closer to pH 5 (Don 

Gasper, West Virginia Division of Natural Resources, 

unpublished data). Upper Red Creek contains a good 

population of creek chub (Semotilus atromaculatus), white 

sucker, and various daces. The headwaters portion of Red 

Creek is chemically suitable for brook trout (marginally), but 

often is too warm for trout because of beaver dams. The 

extreme headwaters of Otter Creek (upstream from the 

wilderness boundary) does contain brook trout. 

Below these headwater reaches, both streams are affected 

by the influx of water from acidic tributary streams. Streams 

such as Fisher Spring Run, Stonecoal Run, and Little 

Stonecoal Run that flow into Red Creek, and Yellow Creek, 

Devil's Gulch, and Moore Run that enter Otter Creek, are 

very acidic and contain elevated concentrations of Al. 

Stonecoal Run typically has a pH of 4.0 to 4.5, and Al levels 

of about 180 to 500 ug/L. Stonecoal Run has a base cation 

concentration of about 90 ueq/L and a S04 concentration of 

about 170 ueq/L; ANC is less than zero. In Yellow Creek 

and Devil's Gulch, pH's between 3.7 and 4.0 and total Al 

concentrations from 400 to 600 ug/L are typical, and pH's 

as low as 3.3 to 3.4 and total Al concentrations as high as 

900 to 1,200 ug/L have been measured during high flow 

conditions. 

Downstream from its headwaters, Red Creek becorrjes too 

acidic to support fish except during low flow periods from 

late spring through the fall. Throughout the Dolly Sods 

Wilderness below the headwater reach, the pH of Red 

Creek typically ranges from the mid 4's to the high 5's. The 

lowest pH's occur in the late winter and in spring during 

snowmelt, and following rain storms. The highest pH's are 

recorded during low flow periods of the summer and fall. 

The average base cation concentration of Red Creek, jyst 

above Stonecoal Run, is about 150 ueq/L, and S04 

averages about 140 ueq/L. ANC's range from less than zero 

to a high of about 15 ueq/L. Within the Dolly Sods 

Wilderness, the only part of the Red Creek system below 

the headwaters that appears capable of sustaining fish is an 

abandoned channel of Red Creek fed by several springs 

and seeps that emerge from bedrock strata of the Mauch 

Chunk Group. This spring-fed channel, with suitable water 

quality and spawning and rearing areas, harbors a small, 

self-sustaining population of brook trout. In the summer and 

fall, fish from this spring-fed channel enter Red Creek and 

may migrate a few miles upstream (Don Gasper, West 

Virginia Division of Natural Resources, pers. commun.). 

With no competition, these fish grow quickly; however, they 

do not appear to survive the acidic springtime conditions in 

Red Creek. 

The chemistry of Otter Creek is altered just before it flows 

into the Otter Creek Wilderness by a facility that adds 

limestone to the water to raise its pH and ANC to sustain a 

brook trout fishery in the stream. Upstream of the liming 

operation, Otter Creek is acidic, with pH's of from less than 

4.0 to about 5.5. The only tributary of Otter Creek in which 

the presence of brook trout has been documented is Turkey 

Run, which flows into Otter Creek from the northwest a few 

miles upstream from the lower Wilderness boundary. It is 

not known if Turkey Run still contains trout; the last 

fisheries survey on this stream was conducted some twenty 

years ago. One other stream in the Otter Creek Wilderness, 

Shavers Lick Run, is chemically suitable for trout in its lower 

reaches, but its fish population has not been documented. 

Shavers Lick Run rises near the lower end of ihe 

Wilderness and does not discharge into Otter Creek. 

There are indications of increased acidity of the streams in 

the Dolly Sods and Otter Creek Wildernesses due to acidic 

deposition. The West Virginia Division of Natural Resources 

has been monitoring water quality and fish populations for 

many years in Otter Creek and other nearby streams. Their 

data show a long-term trend of increasing stream acidity 

and fish population effects in poorly buffered mountain 

streams. In early June, 1990, following several days of 

heavy rain, a pH of 3.7 was recorded in Otter Creek just 

above the liming facility (Barry Edgerton, Monongahela 

National Forest, pers. commun.). Fish populations in Otter 

Creek are artificially maintained by liming, and fish 

population data from Red Creek are insufficient to show a 

trend. Data from other nearby streams show a recent loss of 

fish due to acidification. 

The pH and ANC of Red Creek and its tributaries are 

presently below both the chronic and episodic red line 

values, except for the headwater area and a reach of 

abandoned stream channel fed by several small springs and 

seeps from the Mauch Chunk Group, as described earlier. 

In the absence of the liming operation, the pH and ANC of 

Otter Creek would be below the red line values. The only 

streams in the Otter Creek Wilderness that may be capable 

of sustaining fish populations without liming are Turkey Run 

and Shavers Lick Run. The aquatic ecosystems of the Otter 

Creek and Dolly Sods Wildernesses are under considerable 

stress from a combination of natural and deposition-derived 

acidity. Additional acidic loadings from S and N deposition 

will further stress the aquatic ecosystems, and will 

jeopardize the existing populations of fish and other aquatic 

organisms. 

Current total S and N deposition rates are estimated to be 

21 and 16 kg/ha/yr, respectively, in the Dolly Sods and Otter 

Creek Wildernesses (Table 3). Due to adsorption of 40 to 50 

percent of the depositional S04 load by the soils, the 

effective S deposition rate is estimated to be about 11 to 13 

kg/ha/yr. As the S04 adsorption capacity of the soil is 

depleted, the effective deposition rate will increase and 

eventually approach the actual deposition rate. Since 

stream pH and ANC values already are below the red line 

values (or would be without liming), we estimate the red line 

total S deposition rate for the Otter Creek and Dolly Sods 

Wildernesses, given the eventual saturation of the S04 

adsorption capacity, to be the current effective rate of 11 to 

13 kg/ha/yr. We estimate the red line S + 20 percent of N 

deposition rate to be about 14 to 16 kg/ha/yr. 

15 
P.19 

Available historical data indicate that the natural pH and 

ANC of Red Creek and Otter Creek, in the absence of any 

anthropogenic acid loadings, probably were at or below the 

green line values, and that any additional acid loadings from 

deposition would be detrimental. Thus, we estimate the 

green line S and N deposition rates to be close to 

background levels. 

Wisconsin: Rainbow Lake Wilderness 

The 22 lakes in the Rainbow Lake Wilderness are seepage 

lakes. They receive much of their water from direct on-lake 

precipitation; the remainder is from seepage of 

groundwater. They have no surface water inputs. Several of 

these lakes are sensitive to acidic deposition. The 13 lakes 

for which water chemistry data are available have ANC's 

from about 10 to about 60 ueq/L. Their pH's range from 5.6 

to 6.3, and average about 5.9. Base cation concentrations 

range from about 80 to 170 ueq/L. These are summertime 

data; in the spring, ANC's and pH's may be lower due to 

melting snow. The lakes fall into two groups with regard to 

sensitivity. Eight of the 13 have summer ANC's of about 10 

to 30 ueq/L. The other five lakes are less sensitive, with 

ANC's in the 55 to 60 ueq/L range. 

The base cation and ANC concentrations of seepage lakes 

such as these depend largely on the proportion of water 

supplied by groundwater. A hydrologic study of four 

northern Wisconsin seepage lakes showed that three of the 

lakes with mean ANC's ranging from 21 to 118 ueq/L 

receive from 3 to 15 percent of their water from 

groundwater, while the fourth lake with a mean ANC of 384 

ueq/L receives 30 percent groundwater (Garrison et al. 

1987). The ANC of a seepage lake in Upper Michigan was 

observed to drop from 178 to 22 ueq/L over a 5-year period 

when drought conditions substantially reduced the input of 

ANC-rich groundwater (Webster et al. 1990). 

Fisheries surveys have been conducted on 12 of the 13 

lakes in the Rainbow Lake Wilderness for which water 

chemistry data are available. The two largest lakes contain 

largemouth bass (Mlcropterus salmoides), and another has 

been stocked with rainbow trout {Salmo gairdneri). Several 

hold bluegill, perch, and other panfish, and a variety of 

minnows and rough fish. No fish were found in four lakes. 

The presence or absence of fish appears to be related to 

winter survival. The fishless lakes are among the smallest 

and most shallow of the lakes surveyed. 

On the basis of the relationship between base cation 

concentrations and F value suggested by Brakke et al. 

(1990), a reasonable estimate of the F value for the most 

sensitive of these lakes is about 0.4. However, since most 

of the water in these lakes is from direct on-lake 

precipitation and does not react with the soils and minerals 

in the watershed, cation enrichment probably is minimal. 

The ILWAS model was used to simulate water chemistry 

responses to changes in S deposition in two low-ANC 

seepage lakes, Crystal and Vandercook, in north-central 

Wisconsin (Chen et al. 1986; Garrison et al. 1987). These 

simulations indicated F values of close to zero. We estimate 

F to be about 0.2 for the most sensitive Rainbow Lake 

Wilderness lakes. 

The S04 concentrations of the lakes in Rainbow Lake 

Wilderness range from about 40 to 60 ueq/L. Background 

S04 concentrations for dilute lakes in the Eastern United 

States have been estimated at about 15 ueq/L (Brakke et al. 

1989). This indicates that the Rainbow Lake Wilderness 

lakes have incurred an average S04 increase of about 35 

ueq/L above background concentrations due to 

anthropogenic S deposition. If F = 0.2, then they have 

incurred ANC losses of about 25 ueq/L due to acid 

deposition. 

Two of the 13 lakes for which data are available have mean 

ANC's of 10 to 20 ueq/L, well below the green line value of 

25 ueq/L and into the yellow zone. The mean ANC's of five 

other lakes are about equal to the green line value of 25 

ueq/L—some individual ANC measurements from these 

lakes also fall into the yellow zone. These lake chemistry 

data indicate that the current S deposition rate of about 6 

kg/ha/yr (Table 3) is in the yellow zone between the red line 

and green line values. Only a small increase in S deposition 

would be required to reduce the ANC of the most sensitive 

of these lakes to the red line value of 10 ueq/L. 

On the basis of Galloway et al.'s (1984,1987) estimate of 

background S04 concentration in precipitation of 5 to 7 

ueq/L and an average annual rain and snowfall of about 800 

mm in northwestern Wisconsin, we estimate the 

background S deposition rate on the Rainbow Lake 

Wilderness to have been about 1 to 1.5 kg/ha/yr. Lake water 

S04 appears have increased by about 35 ueq/L over 

background, an increase in S04 of about 7 to 8 ueq/L for 

each kg/ha/yr of S deposition. As a comparison, ILWAS 

simulations of Crystal and Vandercook Lakes (Chen et al. 

1986; Garrison et al. 1987) projected a S04 change of about 

6 to 8 ueq/L for each kg/ha/yr change in S deposition. 

Given an annual average of about 800 mm of precipitation 

and about 300 mm of runoff (Geraghty et al. 1973), a 1 

kg/ha/yr increase in S deposition could increase S04 

concentrations in northern Wisconsin lakes by as much as 

20 ueq/L, if no S04 were retained by reduction in wetlands 

and lake sediments or by adsorption in upland soils. Baker 

et al. (1986) developed a model that showed that in lakes 

with long hydraulic retention times (several years) typical of 

low ANC seepage lakes, S04 reduction in the lake 

sediments can reduce S04 concentrations in the water by 

50 percent or more. On the basis of ILWAS simulations, 

Garrison et al. (1987) estimated that if S04 reduction were 

eliminated, the S04 concentrations of Crystal and 

Vandercook Lakes would increase by almost 100 percent. 

If the F value of these lakes is about 0.2, then an increase 

in the current 6 kg/ha/yr total S deposition rate of about 1.5 

to 2.5 kg/ha/yr would be sufficient to decrease the ANC of 

the most sensitive of these lakes to less than the red line 

value of 10 ueq/L. Similarly, a decrease in S deposition of 

similar proportions could increase the ANC of the most 

16 
P.20 

sensitive lakes to the green line value of 25 ueq/L. These 

estimates compare well to the ILWAS simulation of Crystal 

and Vandercook Lakes in which a 50 percent change in S 

deposition (a change of about 3 kg/ha/yr) was projected to 

cause a 20 ueq/L change in lake ANC (Chen et al. 1986; 

Garrison et al. 1987). We estimate the green and red line S 

deposition rates for the Rainbow Lake Wilderness to be 

about 3.5 to 4.5 kg/ha/yr and 7.5 to 8.5 kg/ha/yr, 

respectively. The corresponding estimated green and red 

line deposition rates of S + 20 percent of N are about 4.5 to 

5.5 and 9.0 to 10.5 kg/ha/yr, respectively. 

Minnesota: Boundary Waters 

Canoe Area Wilderness 

In contrast to the Rainbow Lake Wilderness lakes, most of 

the BWCAW lakes are drainage lakes. Much of their 

hydrologic input is from surface runoff from their 

watersheds. BWCAW waters are moderately sensitive to 

sensitive with regard to acidic deposition. About 75 percent 

of the lakes have ANC's of 200 ueq/L or less, and about 35 

percent have less than 100 ueq/L. However, only about 5 

percent have ANC's below 50 ueq/L, and none is below the 

ANC green line value of 25 ueq/L. Base cation 

concentrations of the most sensitive lakes are about 130 to 

140 ueq/L. The pH's of even the most sensitive lakes 

generally are 6.5 or greater. A small proportion, perhaps 2 

percent, have pH's between 5.5 and 6.5; these are typically 

dark-colored lakes influenced by naturally acidic flrainage 

from peatlands. The most sensitive BWCAW lakes appear 

to have sufficient buffer capacity to handle the present 

depositional loadings of S and N. The fish populations in 

lakes and streams in the BWCAW are typically healthy and 

abundant. 

watershed S04 retention processes, an increase in S 

deposition of 1 kg/ha/yr could increase BWCAW lake SC4 

by 20 to 25 ueq/L. However, considering the importance of 

S04 reduction in lake bottom sediments and in peatlands in 

the watershed, we estimate the actual increase in lake S04 

from each kg/ha/yr increase in S deposition to be about 12 

to 15 ueq/L. Given F values of 0.6, we estimate an ANC 

decrease of 5 to 6 ueq/L in sensitive BWCAW lakes for each 

kg/ha/yr increase in S deposition. 

For the most sensitive BWCAW lakes for which we have 

data, those with ANC's of about 40 ueq/L, we estimate that 

a reduction of 15 ueq/L to the green line ANC value of 25 

ueq/L would result from a S deposition increase of about 2.5 

to 3.0 kg/ha/yr. An additional 2.5 to 3.0 kg/ha/yr would 

further reduce ANC's to the red line value of 10 ueq/L. The 

present total S deposition rate in the BWCAW is about 5 

kg/ha/yr (Table 3). We estimate the green line S deposition 

rate to be about 7.5 to 8.0 kg/ha/yr and the red line S 

deposition rate to be 10 to 11 kg/ha/yr. The green and red 

line values for S + 20 percent of N deposition would be 

about 9 to 10 and 12 to 13 kg/ha/yr, respectively. 

In 1982, the State of Minnesota passed the Acid Deposition 

Control Act. Under this legislation, the Minnesota Pollution 

Control Agency conducted an analysis to determine a S 

deposition limit that would protect the most sensitive lakes 

and streams in Minnesota from acidification. This limit was 

set at 11 kg/ha/yr of wet S04 deposition. From the 

relationship between wet and dry S deposition in the 

3WCAW (Table 3), 11 kg/ha/yr of wet S04 is equivalent to 

about 6 kg/ha/yr of total (wet plus dry) S deposition. This is 

somewhat lower than our green line estimate for the 

BWCAW. 

The most sensitive BWCAW lakes for which we have data 

have ANC's of about 40 ueq/L. They could sustain an ANC 

loss of 15 ueq/L without falling below the 25 ueq/L green 

line value. Given base cation concentrations of 130 to 140 

ueq/L, we estimate (using the method of Brakke et al. 1990) 

the F value of these lakes to be about 0.6. Consequently, 

we estimate that an ANC loss of 15 ueq/L would result from 

a lake S04 increase of about 35 to 40 ueq/L. 

In the BWCAW, the relationship between S deposition rate 

and lake S04 concentrations is difficult to derive from 

comparisons of estimated background precipitation and 

lake S04 concentrations with present values. Many of the 

BWCAW lakes lie on geologic formations that contain 

extensive low-grade sulfide deposits (Sims and Morey 

1972). Therefore, estimates of average background S04 

concentrations for eastern lakes (e.g., Brakke et al. 1989) 

are too low for many BWCAW lakes. Nichols and 

McRoberts (1986) found that lakes near the eastern end of 

the BWCAW contained about 50 ueq/L more S04 than 

would be expected from S deposition alone. 

Average annual precipitation in the BWCAW is about 675 to 

725 mm. Annual runoff averages about 250 to 300 mm 

(Geraghty et al. 1973). In the absence of in-lake or 

Missouri: Hercules Glades Wilderness 

The Hercules Glades Wilderness lies on the southwestern 

portion of the Ozark Plateau. The geologic formations that 

make up the Ozark Plateau are predominantly limestone 

and dolomite. The carbonate minerals in these rocks 

provide a large buffering capacity against the effects of 

acidic deposition. Samples taken from Long Creek, the 

main stream in the wilderness, in the summer of 1990 had 

ANC and base cation concentrations of about 4,000 to 

6,000 ueq/L. Springtime concentrations are probably 

substantially lower but should provide abundant buffering. A 

sample taken from Beaver Creek, which flows along the 

northwestern boundary of the wilderness for a short 

distance, had a pH of 8.0 and an ANC exceeding 2,000 

ueq/L. The impoundments on the White River, just west and 

south of Hercules Glades Wilderness, typically have pH's in 

the 7.2 to 7.8 range and ANC's of 1,000 to 2,000 ueq/L. 

Because of the high buffering capacity of this area, the 

present estimated total S and N deposition rates of 9 and 8 

kg/ha/yr, respectively, (Table 3) pose no threat to aquatic 

ecosystems. We estimate the green line S deposition rate to 

be greater—perhaps much greater—than 30 kg/ha/yr, and 

the S plus 20 percent of N rate to be greater than 35 

kg/ha/yr. We did not attempt to estimate red line values. 

17 

_ 
Information Needs 

P.21 

Inventory and Monitoring 

Workshop participants identified many information needs 

for successful response to PSD permit applications, but 

indicated the primary need was for thorough characterization 

and inventory of the wilderness areas. Existing inventory 

data for each of the wilderness areas in Region 9 should be 

assembled from its many sources and locations, and 

information gaps be filled as soon as possible. The 

biological resources of each area should be characterized, 

and should include listings of aquatic and terrestrial flora 

and fauna, and descriptions of ecosystems. Soils should be 

described to the family level (Soil Survey Staff 1987). 

Bedrock type and geologic formations also should be 

characterized. Information on pollutant delivery to each area 

should be quantified. Particular emphasis should be given 

to identifying threatened and endangered species and those 

that are particularly sensitive to air pollutants. 

Monitoring entails continued measurement of the status of 

the system over time. Monitoring needs for aquatic systems 

include atmospheric loading of pollutants, chemical 

characteristics of stream or lake waters, and presence or 

absence of potentially sensitive receptor species. For 

terrestrial ecosystems, reliable monitoring of species 

richness as well as air quality and deposition is necessary. 

Monitoring for both aquatic and terrestrial systems must be 

consistent and of high quality. 

Workshop participants suggested a sampling protocol of 

collection of water samples 3 times a year in every third 

year. Timing of sampling might include springtime snowmelt 

peak flow, summer low flow, and autumn turnover. Stream 

chemistry often is affected by large precipitation events. 

Chemistry of sensitive seepage lakes may be influenced by 

annual or multiyear precipitation patterns that affect 

groundwater levels and lake inputs. Long-term sampling is 

needed to separate annual and seasonal variations in water 

chemistry from pollutant-induced changes. The "best" 

times for sampling and the intensity of sampling required 

will depend on the area, and more detailed determinations 

are needed. 

Monitoring of biological resources also is needed. Detection 

of population changes for any specified organism is 

extremely difficult due to high natural variation, but 

potentially sensitive receptor organisms should be 

monitored for their presence or absence. Historical records 

should be consulted to establish the existence of previous 

populations of organisms. Birds, fish, aquatic invertebrates, 

amphibians, and diatoms are candidates for monitoring. 

Biomonitoring of vegetation for pollutant injury symptoms 

also can be done. Biomonitoring programs may be limited 

because the sensitivity of many rare and endemic plants to 

air pollutants is not known. 

Monitoring of ozone should be the first priority for terrestrial 

ecosystems. Ozone concentrations can vary significantly 

with elevation, and this elevational gradient should be taken 

into consideration when locating monitoring stations. 

Current ozone effects in wilderness areas also should be 

assessed through biomonitoring. This already has begun on 

the Dolly Sods, Lye Brook, and Great Gulf Wildernesses, 

and can be implemented fairly easily at other sites. Because 

of the restrictions placed on wilderness use, and due to the 

high biological complexity on some of these eastern 

wildernesses, traditional methods of ozone monitoring, 

although well developed, may need some modifications. 

Monitoring of deposition of the major cations and anions in 

precipitation (wet deposition) should continue to be carried 

out at the existing NADP/NTN stations. The Forest Service 

should ensure that funding is maintained for operation of 

NADP/NTN sites that are relevant to Class I wilderness 

areas. In addition to the NADP/NTN network, applicable 

data may be available from several other wet deposition 

networks, for example, MAP3S, UAPSP, CAPMON, and 

APIOS-C (see Sisterson et al. 1990). If no NADP/NTN or 

other network sites are applicable to a certain wilderness, 

provision should be made for establishing and maintaining 

an equivalent monitoring site. 

Water chemistry monitoring should be conducted on a 

subsample of surface waters in each Class I wilderness 

area. This subsample should include the most sensitive 

lakes and streams, or the waters of greatest concern. 

Research Needs 

Dry deposition is an important component of total 

deposition, but is not well quantified. In this report, 

estimates of dry S deposition were derived from the 

Regional Acid Deposition Model (RADM) described by 

Chang et al. (1987) as percentages of wet S deposition. Dry 

N deposition rates, as percentages of wet N deposition, 

were estimated from data from CORE/Satellite sites as 

summarized by Sisterson et al. (1990). Another method of 

estimating dry deposition entails measuring throughfall 

chemistry at specific sites. The throughfall method has been 

used on several research areas. See Sievering (1987) for an 

analysis of the method and Lindberg et al. (1986) for a case 

study. Dry deposition also can be estimated by multiplying 

ambient concentrations by "deposition velocities." Ambient 

concentrations of S and N forms are measured at about 50 

sites in the National Dry Deposition Network (NDDN), 

sponsored by the U.S. EPA. Although estimates of 

deposition velocities are given in the USDA Forest Service's 

Air Resource Handbook, deposition velocities vary 

considerably (orders of magnitude) for different S and N 

species, for different surfaces such as forest, grassland, 

water, and bare rock, and for different atmospheric 

conditions. Pollutant deposition velocities should be 

developed for subareas of each Class I wilderness. 

In mountainous areas, the deposition of pollutants dissolved 

in cloud droplets onto vegetation surfaces at high elevations 

18 
P.22 

can exceed wet plus dry deposition. Cloud deposition 

begins to be important at elevations of about 850 to 900 m 

and increases with elevation. Knowledge of high-elevation 

deposition by any process is sparse, although some 

information is available from the Mountain Cloud Chemistry 

Program (Mohnen 1990). To fill the information gap about 

high-elevation deposition, Lovett and Kinsman (1990) 

suggest an increased density of deposition monitoring sites 

in mountainous regions; specific studies of wet, dry, and 

cloudwater deposition along elevational gradients; and 

investigations of the factors that regulate deposition in 

mountainous areas to allow extrapolation of results to other 

sites. Because of the difficulties of carrying out intensive 

deposition studies in designated wilderness areas, the 

ability to extrapolate data to wilderness sites is important. 

For many pollutants, models that describe the links between 

emissions and pollutant loading are not available. Most 

notably, it is not well known how ozone concentrations at a 

particular location are related to emissions of volatile 

organic compounds. Additionally, research on the relation of 

S02 emissions and S04 exposure is needed. Sorely needed 

is information about the effects of cumulative exposure on 

the ecosystems of concern. Deposition reductions will not 

necessarily be immediately reflected in improvements in 

water quality or diminished effects upon organisms. 

Continued deposition at even lower rates could result in 

acidification of some surface waters. At present, cumulative 

exposure might be best assessed by the use of simulation 

models. I 

To assess cumulative impacts and potential impacts of 

predicted changes in deposition, simulation models such as 

ILWAS (Gherini et al. 1985) and MAGIC (Cosby et al. 

1985a,b) are useful. Such models can be used to estimate 

dose-response functions for individual wildernesses or their 

component parts. These functions are independent of any 

particular PSD, so modeling need only be done once rather 

than in response to each PSD application. Both ILWAS and 

MAGIC have been in use for several years and already may 

have been calibrated and run for watersheds similar to 

many of the Class I areas discussed here. This could 

significantly decrease the cost of data collection and 

calibration. Because of the uncertainties and biases 

inherent in any method, predictions of the response of the 

Class I wilderness areas to acidic deposition should be 

made using a combination of methods, including simulation 

models like ILWAS and MAGIC, empirical steady-state 

models (e.g. Brakke and Henriksen 1989) (with some 

adjustment for in-lake ANC production (Baker et al. 1986) 

where appropriate), and paleolimnological studies of diatom 

communities. The Forest Service should place a priority on 

assembling the appropriate data and running these models 

for all Class I areas in the Eastern Region. 

The procedure described in this report is interim. The 

recommended criteria will change with the dramatically 

changing state of science in air pollution effects. Managers 

and scientists will have to review these changes and adjust 

the criteria and possibly the procedure. We recommend that: 

1. Representatives of the Eastern Region, the Northeastern 

Forest Experiment Station, the North Central Forest 

Experiment Station and Northeastern Area-State & Private 

Forestry periodically review the applicability of this 

screening procedure and jointly recommend changes 

needed in the criteria; 

2. National Forest and research project staff annually meet 

to assure effective inventory and monitoring of resource 

conditions in Class I areas, to assure that managers are 

using recent research results and to help researchers 

understand the problems of managers. 

Acknowledgment 

Participants at the May 1990 Forest Service workshop in 

Oconomowoc, Wisconsin, provided advice on a screening 

procedure for identifying impacts to the AQRVs of National 

Forest Eastern Region Class I air quality areas. Workshop 

participants also were given an opportunity to review the 

draft of this report; we also obtained peer review by 

scientists who were not at the meeting. Dr. Lewis Ohmann 

of the North Central Forest Experiment Station, Dr. 

Christopher Eagar of the Northeastern Forest Experiment 

Station, and James Byrne of the Forest Service's 

Washington Office provided review comments on the 

final draft. 

19 
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22 
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Appendix I 

General Description of Air Quality-Related Values 

for Eastern Region Class I Areas 

DOLLY SODS WILDERNESS 

Location: Size: 10,215 acres 

Monongahela National Forest Designated: 1975 

Eastern West Virginia 

Latitude: Elevation: 2,620 to 

38° 57'30" to 39° 02'30" 4,122 feet 

Longitude: 

79° 19'to 79° 24'30" 

General Description 

Dolly Sods Wilderness, which is on the Allegheny Plateau, 

is named for the pioneer Dahle family which owned and 

cleared some of the land for pasture ("sods" is an old term 

for grassland). It is about 10 miles from Petersburg, West 

Virginia, and 175 miles from Washington, D.C. 

Evidence of human presence in the area is apparent. 

Remnants of the extensive network of roads and trails 

necessary to harvest timber in the late 1800's and early 

1900's can still be seen. Grazing, once an important use, no 

longer occurs. A harsh climate resembling that found much 

farther north is a major influence. 

Vegetation. Second-growth beech, birch and maple, dense 

rhododendron, laurel, blueberry, and other heath vegetation 

are common, as are wetland communities. Red spruce is 

common in the upper elevations, and some oak is found at 

lower elevations. 

Wildlife. Deer, black bear, bobcat, beaver, grouse, turkey, 

woodcock, rabbit, and numerous other birds, mammals, 

amphibians, and reptiles, including the eastern timber 

rattler, inhabit the wilderness. 

Weather. The climate is severe and temperatures are cool. 

Frost can occur at any time but is rare during most of the 

summer. Prevailing westerly winds blow most of the time, 

and the upper elevations often are covered by clouds or fog. 

Annual precipitation is about 55 inches. Frequent and 

sudden weather changes are common. 

Air Quality-Related Values 

Scenic Beauty. The scenic beauty of the Dolly Sods 

Wilderness is a primary attraction for its users. Features 

include rock escarpments which provide panoramic views of 

the deeply incised Red Creek, the high-elevation plateau, 

mountain summits, and surrounding ridge lines. Visual 

diversity is enhanced by contrasting wetland/bog 

associations, high-elevation spruce, mixed hardwoods, and 

early successional vegetation such as blueberry. Users 

enjoy the sense of solitude and a variety of landforms and 

associated vegetative communities and wildlife. Extensive 

thickets of rhododendron and mountain laurel throughout 

the wilderness provide pleasing diversity during their 

flowering period. Lower Red Creek is rock-strewn and fast 

flowing, and periodically flows out of the channel. Its waters 

are stained reddish-brown from the wetlands and other 

vegetation in the creek's upper reaches. Most of the 

recreation use within the Dolly Sods Wilderness occurs 

along Red Creek. 

Vegetation. The overstory is dominated by a mixture of 

second-growth northern and Allegheny hardwoods which 

are 60 to 80 years old. There are separate components of 

oak, heath, and associated species. Spruce is present at 

higher elevations. There are scattered pockets of 

wetland/bog associations, and about 1000 acres in a 

grass/forb stage. Extensive thickets of rhododendron and 

mountain laurel are found throughout the wilderness. 

Water. Red Creek is the dominant water resource of this 

wilderness. Fed by numerous tributaries, the creek is 

stained reddish-brown with tannic acids from headwater 

wetlands and other vegetation. All waters are acid and 

unproductive. Red Creek has historically been a marginal 

fishery. 

Odor. The natural smells of the forest are an important 

value to wilderness users. Conifers, hardwood leaf litter, 

and wildflowers provide pleasant odors which enhance the 

outdoor experience. 

Wildlife. A variety of mammals, birds, reptiles, and 

amphibians inhabit the wilderness, including the Cheat 

Mountain salamander, a federally listed threatened species. 

Some nongame fish species are present, including the 

uncommon pearl dace. There is a small population of native 

brook trout in Red Creek. 

OTTER CREEK WILDERNESS 

Location: Size: 20,000 acres 

Monongahela National Forest Designated: 1975 

Eastern West Virginia 

Latitude:. Elevation: 1,830 to 

38° 55'30" to 39° 03'30" 3,912 feet 

Longitude: 

79° 35' to 79° 42' 30" 

General Description 

Otter Creek Wilderness is located about 10 miles northeast 

of Elkins, West Virginia. Otter Creek runs 11 miles through 

a valley and is followed by a trail along its 1,200-foot drop to 

the Dry Fork River. Parallel mountain ridges that reach 

heights of 3,900 feet encircle a 4-mile-wide oval watershed 

with numerous small streams flowing into Otter Creek. 

Vegetation. The wilderness was logged during the late 

1800's and early 1900's and again between 1958 and 1972. 

Most of the wilderness is now forested with second-growth 

stands of northern hardwoods and Allegheny mixed 

hardwoods. Nearly impenetrable stands of waxy-leaved 

rhododendron cover extensive portions of the area, making 

off-trail hiking difficult. Red spruce occupies some of the 

higher elevations and there are some small freshwater 

wetland communities. 

23 
P.27 

Wildlife. Black bear, white-tailed deer, bobcat, beaver, 

wild turkey, grouse, snowshoe hare, cottontail rabbit, 

salamander, and numerous other bird, mammal, amphibian, 

and reptile species, including the timber rattler, inhabit the 

wilderness. There is a small population of brook trout in 

Otter Creek due to improved water quality from an artificial 

liming station. 

Weather. Cool temperatures prevail and frost may occur 

during any month of the year. The area receives about 55 

inches of precipitation annually. 

Air Quality-Related Values 

Scenic Beauty. The scenic beauty of the Otter Creek 

watershed is highly valued by its users. Panoramic views of 

nearly the entire watershed are obtained from a number of 

large rock cliffs. The visual resource includes the Otter 

Creek valley and mountains which rise more than 3,800 feet 

above sea level. Visual diversity is provided by a number of 

small freshwater wetlands and rock outcrops. Many users 

experience a sense of solitude and peace when they are in 

the mature, second-growth forest that also provides visual 

diversity through a variety of tree and shrub species. Otter 

Creek itself is a clear, clean mountain stream, tumbling over 

boulders in alternating small waterfalls and pools. Much of 

the recreation use in the wilderness occurs in and near 

Otter Creek. 

Vegetation. An overstory of second-growth northern 

hardwoods and Allegheny mixed hardwoods dominates the 

Otter Creek Wilderness. Red spruce in the higher elevations 

provides visual and vegetative diversity year around. A 

59-acre patch of virgin red spruce and hemlock on Shavers 

Mountain provides a remnant of the prelogging era timber 

found in Otter Creek. Another interesting feature is a 

50-year-old stand of planted Norway spruce, approximately 

200 acres in size. Extensive rhododendron thickets are 

common, and their seasonal flowering provides an attractive 

understory. Otherwise, the ground and herbaceous 

understory is lacking in the richness and diversity found at 

other low-elevation mesic sites. There are limited areas of 

limestone bedrock where a more diverse understory 

vegetative mix provides visual variety. Small freshwater 

wetlands and their associated plant communities provide 

additional vegetative diversity. 

Water. Otter Creek is the dominant water resource of this 

wilderness. Several smaller acid and unproductive 

tributaries flow into the main stream. Water quality in Otter 

Creek is not representative of natural conditions due to an 

artificial liming facility that operates in its headwaters. 

Waters are cold and clear, and tributaries generally are 

stained brown from tannic acids. Water quality is important 

to wilderness users for drinking purposes. Water quality of 

Shavers Lick Run, a perennial stream within the wilderness 

that is not a tributary to Otter Creek, is better than that of 

the tributaries. 

Odor. The natural smells of the forest are an important 

value to wilderness users. Conifers, hardwood leaf litter, 

and wildflowers provide pleasant odors which enhance the 

enjoyment of being outdoors. 

Wildlife. Wilderness visitors enjoy a variety of game and 

nongame animals. Otter Creek is home to numerous birds, 

large and small mammals, reptiles, amphibians, and fish. 

The Virginia northern flying squirrel, a federally listed 

endangered species, occupies the upper elevations of the 

wilderness. The threatened Cheat Mountain salamander is 

found in the wilderness uplands. There are populations of 

native brook trout in Otter Creek due to improved water 

quality from the artificial liming facility at its headwaters. 

GREAT GULF WILDERNESS 

Location: Size: 5,552 acres 

White Mountain National Forest Designated: 1975 

North Central New Hampshire 

Latitude: Elevation: 1,680 to 

44° 15' 00" to 44° 22' 30" 5,807 feet 

Longitude: 

71°15'00" 

General Description 

The Great Gulf Wilderness is shaped like a large 

amphitheater—the northern and western boundaries follow 

the ridge of the Presidential Range. The steep cliff-like walls 

of this range surround a clear mountain lake and numerous 

cascading streams. The wilderness features high mountain 

peaks, glacial cirques, and unique tundra and krummholz 

vegetation. 

The Great Gulf Wilderness is small; roads parallel the 

boundary for considerable distances. Nearby is heavily used 

Mt. Washington State Park. As a result, the wilderness 

receives much day use. 

Vegetation. Hardwoods cover the lower slopes; mixed 

birches, maples, and spruce-fir blanket midslopes; and pure 

spruce-fir covers the upper slopes. Parts of the major ridges 

are above timberline with krummholz vegetation. 

Wildlife. Wildlife is not a prominent feature, though deer, 

black bear, grouse, hare, and a variety of birds associated 

with high mountain slopes are found in the wilderness. 

Weather. The weather is strongly influenced by the 

elevation and geographic location. The Great Gulf 

Wilderness lies between two major paths of weather-system 

movement which can cause dramatic changes in local 

weather conditions. It is not uncommon for temperatures 

to be in the sunny 80's in the valleys and 30 to 40 degrees 

cooler on the summits with high winds, rain, and fog. Winds 

in excess of 100 miles per hour have been recorded for 

24 
P.28 

every month of the year. Average annual precipitation is 60 

inches with 25 to 30 percent falling as snow; average 

annual snowfall is 160 to 240 inches. 

Air Quality-Related Values 

Because of contiguity and similarities, AQRVs for this 

wilderness are included with those for the Presidential 

Range-Dry River Wilderness. 

PRESIDENTIAL RANGE-DRY RIVER WILDERNESS 

Location: Size: 27,380 acres 

White Mountain National Forest 

North Central New Hampshire Designated: 1975 

Latitude: 

44° 07' 30" to 44° 15' 00" Elevation: 880 to 

Longitude: 5,413 feet 

71° 15'00" to 71° 22'30" 

General Description 

The Presidential Range-Dry River Wilderness features 

mountain peaks ranging from 3,000 to 5,400 feet, some 

areas above timberline, distinctive geologic formations, and 

unique biological communities. The northwest boundary is 

the ridge of the Presidential Range and the the Appalachian 

Trail (a National Scenic Trail) runs along the northern and 

western boundary. 

Vegetation. Hardwoods occupy the lower slopes; mixed 

birches, maples, and spruce-fir blankets the midslopes; and 

pure spruce-fir covers the upper slopes. A portion of the 

major ridges is above timberline with typical krummholz 

vegetation. 

Wildlife. Wildlife is not a prominent feature of this wilderness, 

though deer, black bear, grouse, hare, and a variety of birds 

associated with high mountain slopes are found here. 

Weather. The weather is strongly influenced by the elevation 

and geographic location. The Presidential Range lies 

between two major paths of weather-system movement 

which can cause dramatic changes in local weather 

conditions. It is not uncommon for temperatures to be in 

the sunny 80's in the valleys and 30 to 40 degrees cooler 

on the summits with high winds, rain, and fog. Winds in 

excess of 100 miles per hour have been recorded for every 

month of the year. Average precipitation is 60 inches with 

25 to 30 percent falling as snow; average annual snowfall is 

160 to 240 inches. 

Air Quality-Related Values 

The Great Gulf and Presidential-Dry River Wildernesses are 

separated by the summit of Mt. Washington. Because of 

their proximity and because they have numerous features in 

common, including geology, water resources, visual range, 

alpine areas, wildlife, and vegetation, the AQRVs for both 

areas are nearly identical. 

Scenic Beauty. The interplay of rugged form and varying 

vegetation makes both wildernesses highly scenic. They are 

dominated by high mountain peaks, large expanses above 

timberline, distinctive geologic formations, and vegetative 

communities ranging from deciduous low-elevation forests 

to unique alpine vegetation. Rock capped peaks and ridge 

lines provide outstanding scenic vistas. 

As reported in earlier planning efforts, "...the rugged 

character of the slopes and surrounding peaks (in the Great 

Gulf Wilderness) which shut in the valley, lends a feeling of 

remoteness" and "The steep timbered slopes and valleys 

and rugged rock capped mountain peaks (in the 

Presidential Range/Dry River Wildernesses) allow one to 

find the solitude and peace one needs in the populous 

Northeast to refresh one physically and spiritually." 

Vistas are an especially important component of the scenic 

values of these areas. The high elevations in and around 

these wildernesses allow views of many of the peaks and 

valleys surrounding the northern part of the White Mountain 

National Forest. The elevations also place portions of the 

wildernesses into full view for many miles around. 

Views from the alpine zone, particularly that in the 

Presidential Range, make these wildernesses some of the 

most heavily hiked areas in the National Forest. The Great 

Gulf and Presidential Range/Dry River Wildernesses 

provide considerable enjoyment for visitors looking into the 

wildernesses from outside their boundaries. The roads 

encircling the areas offer scenic views of extremely varied 

and distinctive terrain and vegetation during and after the 

color seasons. The opportunity to experience these 

wilderness vistas is partly responsible for the great number 

of visitors to this part of New Hampshire. 

Vegetation. There are four distinct biotic communities in 

these two wildernesses: alpine, subalpine, spruce-fir, and 

deciduous forest communities. Some of these are unique 

and important in themselves; others are important because 

their presence within the wilderness lends diversity in 

habitat and in experiences for recreationalists. 

Within and surrounding the Great Gulf and the Presidential 

Range/Dry River Wildernesses is the largest alpine area in 

the Eastern United States, commonly called the Presidential 

Range alpine zone. In this region there are approximately 

13 square miles of alpine plant communities. The largest 

single unit of this unique habitat is the Presidential Range 

alpine zone in the White Mountain National Forest, which 

covers approximately 7.5 square miles. 

The alpine plants are an important resource of this zone. 

Many are at the extreme southern limit of their range. There 

are only about 110 species of plants above timberline, 

approximately 75 of which are considered true alpine 

plants. Of these, one species, Potentilla robbinsiana, is 

found nowhere else in the world. 

25 
P.29 

The subalpine biotic community is often termed the 

"stunted forest." It represents the transition from the 

spruce-fir community to the krummholtz to the alpine 

community. Vegetation here is heavily impacted by wind, 

snow, and ice. Trees are a tangled and dense mat of birch, 

spruce, and fir which rarely exceed 15 feet in height. There 

is potential habitat here for the northern bog lemming and 

the Canada lynx. 

The spruce-fir biotic community consists of high-elevation 

spruce-fir stands. Trees here attain normal height and the 

canopy appears as a mosaic of spruce-fir tops, dead masts, 

and small openings created by fallen dead trees. Soils are 

shallow to ledge and slopes generally are steep. With its 

protection within a wilderness and the lack of logging 

impacts from earlier years, this stand can continue to evolve 

as an old-growth stand. 

Deciduous communities are found at lower elevations in the 

two wilderness areas. Species consist of mixed northern 

hardwoods along with some eastern conifers along stream 

bottoms. It appears as a normal deciduous forest setting 

from within and as an unbroken canopy from higher 

viewpoints. The importance of this community relates to the 

diversity it provides, its unbroken canopy, its spectacular 

colors in fall, and its potential as a protected old-growth 

forest. 

Wildlife. Several species of animals found in the alpine zone 

are of particular concern. Among them are the northern bog 

lemming, and two species of butterfly, the White Mountain 

Fritillary and the White Mountain arctic. The greatest 

population of the latter is found in the Great Gulf in an area 

called the "Cow Pasture." 

Water. Cool, crystal-clear streams and ever present cascades 

are an important component of the "close-up views and 

sounds" in the two wildernesses. The associated biologic 

communities of these water bodies also add to the diversity 

of the areas. Many of the larger streams contain populations 

of wild brook trout which are isolated from downstream 

populations by ledges, cascades, and waterfalls. Moss 

carpets the rocks of the smaller headwater streams. 

With few high-elevation ponds in the White Mountains, the 

three named ponds within the two areas are unique. These 

small ponds, which could be called tarns or cirque lakes, 

are small and shallow with small drainage basins. Star Lake 

is a 1-acre pond located above 5,000 feet in the Great Gulf 

Wilderness. Spaulding Lake is a 0.2-acre pond located at 

4.300 feet in the Great Gulf. Desolation (or Red) Pond is a 

shallow 3-acre pond located at 3,800 feet in the Presidential 

Range/Dry River Wilderness. 

The Great Gulf has two major tributaries to the Peabody 

River: the West Branch of the Peabody and Parapet Brook. 

Numerous smaller mountain streams drain high in this 

watershed. The Presidential Range/Dry River has a major 

tributary to the Saco River: the Dry River. The upper half of 

the Rocky Branch watershed, another major Saco River 

tributary, also is within this wilderness. There are numerous 

tributary streams draining into both rivers. 

Odor. Part of the experience associated with a visit to the 

wilderness is the natural scents of the surrounding forest. 

The smell of fallen leaves, the scent of a rainstorm, sweet 

odors from balsam fir, and the crisp, clean smell above tree 

line all contribute to the visitor's experience. 

LYE BROOK WILDERNESS 

Location: Size: 15,503 acres 

Green Mountain National Forest 

South Central Vermont Designated: 1975 

Latitude: 

43° 07' 30" Elevation: 800 to 

Longitude: 2,900 feet 

73° 00' 

General Description 

Named after Lye Brook, which flows through the western 

half of the area, Lye Brook Wilderness is located on a highcountry plateau with lakes, bogs, and three hollows where 

brooks flow off the plateau and into the valley below. Lye 

Brook Falls is one of Vermont's highest waterfalls. In 1916, 

a fire created a large meadow-like opening known as "The 

Burning," which runs along the ridgetop in the 

southwestern part of the area. 

The area was extensively logged in the early 1900's. A 

network of railroad lines carried the timber from the plateau 

down to Manchester. Remnants of railroad grades and old 

logging roads remain throughout most of the area. 

Weather. The general climate is cool year round. Summer 

temperatures range from 40°F at night to 80°F during the 

day. Average winter temperatures range from -10°F at 

night to 25°F during the day. Frequent and sudden weather 

changes are common. Snow usually falls at higher 

elevations by late November and lasts until early April. 

Vegetation. Approximately 80 percent of the area has 

stands of northern hardwoods—maple, beech, and birch. 

Other important species are red spruce, balsam fir, and 

hemlock. 

Wildlife. White-tailed deer, black bear, turkey, and beaver 

are common. Small ponds and streams contain brook and 

brown trout. 

Air Quality-Related Values 

Scenic Beauty. The wilderness sits on a plateau on the 

western edge of the Green Mountains. Much of what a 

person sees is dominated by the surrounding vegetation. 

At times it can be like walking through a green tunnel. 

Openings provide views of Stratton Mountain to the 

northeast and Mount Equinox to the west. Views also afford 

glimpses of the valley that lies between the Green and 

Teconic Mountains. Lye Brook Falls, one of the highest falls 

in the area, is steep and ledgy. Portions of the Brook and 

Falls are shaded by ancient hemlock and fir. 

26 
P.30 

Vegetation. The forest within the wilderness is a mixture of 

spruce-fir and northern hardwood stands. Remnants of the 

original spruce-fir forest can be found on the steep slopes 

near Lye Brook. Most of the wilderness was logged earlier 

in this century, so most trees are less than 80 years old. 

Paper birch is giving way to spruce and hardwoods. 

"The Burning," a 200-acre opening created by a 

devastating forest fire in 1916, is dominated by shrubs 

and scattered white pines. 

Wildlife. The wilderness forms a core of mature, closedcanopy vegetation, habitat necessary for the survival of 

"interior" dwelling species. These species are not adapted 

to life outside of closed canopy woodlands and suffer 

greatly from predation and parasitism when forced to dwell 

near open lands. Several neotropical immigrant songbirds 

fall into this category, including Blackburnian and wormeating warblers. 

Water. Two significant attractions to the wilderness are Lye 

Brook and Bourn Pond. Lye Brook flows the length of and is 

contained almost entirely within the wilderness. The stream 

is a headwater tributary to Battenkill, a world-famous trout 

fishery. Lye Brook has its own native brook trout fishery. 

Bourn Pond is a popular dispersed recreation and backpack 

camping area. The pond attracts a variety of wildlife. Loons, 

which have become uncommon within Vermont, are seen 

on the pond. The pond tends to be acidic with a pH range of 

5.0 to 5.5. Dissolved organic matter gives the pond a light 

tea color. The acid neutralization capacity is nearly zero and 

dissolved aluminum is abnormally high. 

Odor. Lye Brook is characterized by a variety of natural 

woodland odors. The smell of moldering hardwood leaves is 

evident through the hardwoods. White pines lend a distinct 

fragrance to "The Burning," which contrasts with the more . 

pungent odor of nearby boggy spruce stands. The variety of 

scents around Bourn Pond changes with the seasons and 

even the time of day. 

HERCULES GLADES WILDERNESS 

Location: Size: 12,314 acres 

Mark Twain National Forest 

Southern Missouri Designated: 1976 

Latitude: 

36° 37' 30" to 36° 45' Elevation: 760 to 

Longitude: 1,360 feet 

92° 50' 30" to 93° 00' 

General Description 

Hercules Glades Wilderness, 60 miles southeast of 

Springfield, consists of open grassland, forested knobs, 

steep rocky hillsides, narrow drainages, and limestone rock 

outcroppings. There are three high knobs that stand out 

from the outer high ridges: Upper and Lower Pilot Knobs, 

and Coy Bald. 

From the late 1800's to the 1950's, any area not fenced was 

considered "open range" and the glades were heavily 

grazed by large numbers of horses, cattle, and hogs. 

Today, cattle grazing is still permitted within the area. 

Vegetation. The thinnest soils have a prairie vegetation 

intermingled with eastern redcedar, smoketree, winged elm, 

aromatic sumac, chinkapin, and post oak. As the soils 

become deeper, larger trees dominate with a mixture of 

chinkapin oak, white ash, post oak, blackjack oak, and 

eastern redcedar. 

The glade areas support grass species common to the great 

prairies: big and little bluestem, Indian grass, prairie 

dropseed, side oats grama, and switchgrass are common. 

Associated forbs include black-eyed susan, several species 

of coneflower, shooting star, Missouri primrose, and prairie 

clover. Rare, threatened and endangered plants such as 

ciliate bluestar, blazing star, stonecrop, and treleases 

larkspur also are found on the glades. 

Wildlife. Wildlife within the area is typical of the glade 

country. Big game consists of white-tailed deer and wild 

turkey. Small game includes squirrel, raccoon, rabbit, fox, 

and bobcat. Bird life includes quail, hawk, owl, and 

numerous small songbirds. Other wildlife found only in the 

glade country because of their relation to the prairie grass 

communities include collared lizard, stinging scorpion, road 

runner, and the Bachman's sparrow. 

Weather. The Ozark climate is mild enough to make visits 

possible throughout the year. Peak use seasons are spring 

and fall. Hercules Glades contains limited open-water 

sources and only portions of Long and Cane Creeks contain 

water year round. 

Air Quality-Related Values 

Scenic Beauty. The scenic beauty of the Hercules Glades 

Wilderness is unique in the Ozark Region of south Missouri. 

The rugged landscape is characterized by high knobs, 

locally known as balds, which offer a spectacular view of the 

rugged landscape, and contrasting vegetative communities 

featuring both a tall grass prairie and a forested landscape. 

Visitors to the wilderness can, with a short hike, experience 

panoramic views and visual contrasts between the forest 

and tall grass-prairie vegetative communities from either or 

both of the twin Pilot Knobs, two high balds from which the 

entire wilderness area can be viewed. The most heavily 

visited spot in the wilderness is a waterfall on Long Creek. 

Vegetation. Vegetation within the Hercules Glades 

Wilderness is a study in contrasts, and perhaps its most 

outstanding natural feature. At one extreme is the oakhickory forest. At the other are extensive areas of open, 

tall grass-prairie vegetation featuring flowers, grasses, 

and forbs. 

27 
P.31 

Water. Long Creek, which flows through the center of the 

wilderness, is an intermittent stream but has pools of water 

throughout the year. The entire watershed of Long Creek is 

contained in the Wilderness. Moderate rainfall is sufficient 

for water to flow swiftly down Long Creek over dolomiticlimestone boulders and natural steps, giving the creek an 

appearance of having thousands of small waterfalls. 

Tributaries to Long Creek are the numerous upland 

waterways or hollows which, due to the high runoff potential 

of the shallow soils, also become swiftly flowing streams 

during rainstorms. The chemistry of the water is dominated 

by calcium and magnesium bicarbonates, and pH is slightly 

alkaline. Nutrient levels are low and, in the absence of 

storm water runoff, stream waters are remarkably clear. 

Wildlife. Visitors to the Hercules Glades Wilderness Area 

have the unique opportunity to observe wildlife indigenous 

to both forests and prairie lands. The wildlife includes many 

large and small mammals, reptiles, and birds. Unique and 

unusual species of nongame birds are the bald eagle, redtailed hawk, great horned owl, great blue heron, and 

pileated woodpecker. 

Species dependent on the tall grass prairie community are 

the collared lizard, stinging scorpion, road runner and 

Bachman's sparrow. Rare, threatened or endangered 

species include Bachman's sparrow, Cooper's hawk, snd 

the long-tailed weasel. Reptiles found in the forest, forest 

fringe, or prairie areas include the copperhead, pygmy 

rattlesnake, and eastern timber rattlesnake. Fish species 

include largemouth and smallmouthed bass, rock bass, 

green sunfish, longear sunfish, and numerous species of 

suckers and minnows capable of existing in an intermittent 

stream. 

Odor. The natural odor of a combination of forest and 

grassland prevails and enhances one's enjoyment of the 

area. 

Vegetation. Maple, white pine, balsam fir, aspen, and paper 

birch are dominant tree species within the wilderness. 

Wildlife. Deer, black bear, ruffed grouse, red fox, skunk, 

otter, beaver, muskrat, weasel, snowshoe hare, grey 

squirrel, mink, loons, woodpeckers, warblers, flycatchers, 

sparrows, jays, crows, finches, hawks, owls, waterfowl, bald 

eagles, bass, perch, trout, and bluegill are common. 

Weather. Summers are pleasantly cool and breezy with a 

few days of 90-degree temperatures each year. Winter 

nights can drop to -30°F or lower. Precipitation averages 

30 inches a year and falls mostly during the summer 

months. Snow usually begins in November and reaches a 

depth of 24 to 36 inches. 

Air Quality-Related Values 

Scenic Beauty. Visitors in the spring and summer experience 

a lush, green, northern hardwood forest, colorful wildflowers, 

and small kettle lakes of the hummocky terrain. Autumn 

presents a dazzling array of colors and, as the leaves fall, 

the hummocky topography created by ancient glaciers is 

more easily seen. Subtle changes in topography are most 

evident in winter when snow covers the ground and 

deciduous leaves no longer obscure one's view. 

Water. The Rainbow Lake Wilderness is noted for its 

beautiful lakes, which provide a rich habitat for fish, 

furbearers, and aquatic plants. The lakes provide recreation 

opportunities for anglers, naturalists, and canoeists. The 

wilderness contains 22 kettle lakes that range in size from 1 

to 33 acres. Water enters these landlocked lakes by way of 

direct precipitation and underground flow from the 

watershed and leaves by subsurface seepage and 

evaporation at the surface. The lake water is extremely soft 

and low in nutrients and dissolved minerals. 

RAINBOW LAKE WILDERNESS 

Location: Size: 6,388 acres 

Chequamegon National Forest 

Northwestern Wisconsin Designated: 1975 

Latitude: 

46° 22' 30" to 46° 27' 30" Elevation: 1,100 to 

Longitude: 1,325 feet 

91° 15'to 91° 22'30" 

General Description 

Rainbow Lake Wilderness is a densely vegetated, primitive 

forest landscape containing 15 undeveloped lakes that are 5 

acres or larger in size, and nine ponds. All the lakes and 

ponds are landlocked; there are no streams. Six miles of the 

North Country National Scenic Trail traverse the area. Old 

logging roads provide access to other parts of the wilderness. 

Visitors to the wilderness gain access to 18 of the lakes 

along upland shorelines and are able to see several feet 

into the clear or light brown water. Four of the lakes have a 

rich, dark stain due to peatlands. 

Vegetation. The vegetation contributes significantly to the 

scenic beauty, variety, and richness of the wilderness. 

Northern hardwood forest is the dominant vegetation. 

Wildlife. The wilderness contains a variety of large and 

small mammals, birds, and fish. Unique species include the 

fisher, pileated woodpecker, and ovenbirds. The common 

loon inhabits some lakes. Although rarely seen, timber 

wolves enhance the wilderness's character and the 

experiences of visitors. At least one wolf regularly uses the 

Rainbow Lake Wilderness, and other wolves make 

occasional use of the area. 

Odor. The fragrence of natural odors is a subtle but integral 

part of the wilderness experience. Leaf litter, conifers, fungi, 

water, and wildflowers provide a pleasant aroma. 

28 
P.32 

BOUNDARY WATERS CANOE AREA WILDERNESS 

Size: 1,086,954 acres 

Designated: 1964 

Location: 

Superior National Forest 

Northeastern Minnesota 

Latitude: 

47° 45' to 48° 30' 

Longitude: 

90° 00' to 92° 30' 

Elevation: 1,260 to 

2,301 feet 

General Description 

The northern lakes and rivers of the Boundary Waters 

Canoe Area Wilderness border Canada and form part of the 

"Voyageurs Highway" of the fur trade. A portion of the area 

was set aside in 1926 to preserve its primitive character. In 

1939, additional area was declared roadless, and in 1964 

the wilderness received its present designation. 

Pristine lakes formed when glacial ice melted centuries 

ago—more than 1,100 lakes are 10 acres or larger. Heavily 

forested land, rock formations, wetlands, and lakes 

dominate the landscape. 

Vegetation. The variety of flowers in this wilderness 

includes subarctic species and nearly 30 native species of 

wild orchids. Principal conifers are jack pine, white pine, 

and red pine. Also common are white and bladk spruce, 

balsam fir, northern white-cedar, and tamarack. Principal 

broad-leaved trees are quaking aspen and paper birch. 

Wildlife. White-tailed deer, moose, black bear, fisher, loon, 

and the last substantial population of timber wolves in the 

contiguous United States inhabit the wilderness. Game fish 

include walleye, northern pike, lake trout, and 

smallmouthed bass. 

Wildlife. Wildlife viewing or experiencing evidence of wildlife 

Weather. The area has variable temperatures and rain from <e-9-. observing tracks or hearing howls and bird calls) is 

highly valued by BWCAW users. Hundreds of species of 

birds, mammals, reptiles, amphibians, and insects inhabit 

the wilderness. The BWCAW is one of the last vestiges of a 

viable timber wolf population in the United States. The 

sounds of a distant howling wolfpack have formed a lasting 

impression on the part of many users who have camped 

overnight in or near the wilderness. Campsite-raiding black 

bears often form a similar though sometimes less favorable 

impression. 

Water. Approximately 1,175 lakes of 10 acres or larger 

comprise 260,000 acres (24 percent) of the BWCAW 

surface area. The unique opportunity for recreational 

canoe/boat travel offered by high-quality interconnected 

lakes and waterways in a largely undisturbed scenic forest 

environment was the primary force behind the wilderness 

designation for the BWCAW. 

Fifty-seven percent of the lakes have an acid neutralizing 

capacity less than 200 ueq/L, but only 1 percent has a pH 

less than 6. Seventy percent of the lakes are considered 

"dark water" due to dissolved organic carbon resulting from 

extensive peatland. 

Bedrock exposures are a common feature, shaping the 

beds, shores, and bottoms of BWCAW lakes and streams. 

The presence of sulfide ores in bedrock likely contributes to 

relatively high concentrations of background sulfate in some 

of these waters. 

Lakes and streams are habitat for walleye, northern pike, 

bass, crappie, sunfish, lake, brook, and brown trout, and 

several other fish species. Fishing is a popular wilderness 

use. 

Vegetation. BWCAW is characterized by the species 

associated with the northern Minnesota Glacial Lake Basin. 

Visual diversity is highest during the fall. Ground and 

herbaceous understory of native berries and aquatic 

species like wild rice are gathered by some recreationists 

and are a valuable food source for many animal species. 

Many species of sensitive plants, including ram's-head 

ladyslipper and northern comandra, inhabit portions of the 

BWCAW. Lichen flora of the BWCAW is diverse, and lichen 

species known to be sensitive to air pollutants are common 

throughout the area (no significant voids in distribution). 

May through September. Average high-low temperatures: 

77° to 42°F; days of rain: 14 to 16 per month. Average 

seasonal temperatures are 42°F in spring, 64°F in summer, 

45°F in fall, and 12°F in winter. 

Air Quality-Related Values 

Scenic Beauty. The scenic beauty of the BWCAW is highly 

valued by its users. Visual experiences encountered by 

most users consist of shoreline views and inspiring waterreflected sunsets across lakes/rivers from campsites, 

portages, or midlake vantage points (from boats or canoes). 

Outstanding shoreline features include lichen-covered 

bedrock cliffs and boulders; boulder-strewn lake inlets and 

outlets; waterfalls and rapids; shoreline wetlands with 

sphagnum, labrador tea, or leather leaf and sparsely 

timbered with black spruce or tamarack; the big-tree 

character of individual or clustered old-growth red and white 

pine, and the contrast established by intermingled aspen 

and conifer stands. 

Bald eagles and osprey are common near the shorelines of 

lakes and rivers, and these birds and their nests are 

commonly seen by boaters and canoeists. Common loons 

are plentiful, their sighting and calls an expected part of the 

BWCAW experience for most wilderness users during the 

open-water season. 

Odor. The natural smells of the forest are an important 

value to wilderness users. Odors in this wilderness are 

associated with natural features such as conifers and 

wildflowers and the sulfurous odors of gases that escape 

from swamps and shallow lakes. 

29 
P.33 

Appendix II 

Additional Information 

Protocol for Monitoring Atmospheric Deposition 

U.S. Environmental Protection Agency. 1977. Quality 

assurance handbook for air pollution measurement 

systems, vol. II. Ambient air specific methods. 

EPA-600/4-77-027a. Research Triangle Park, NC: U.S. 

Environmental Protection Agency. 

General Reference for 

Estimating Atmospheric Deposition in Region 9 

Pinkerton, J. A.; Lefohn, A. S. 1987. The characterization 

of ozone data for sites located in forested areas of 

the eastern United States. Journal of the Air Pollution 

Control Association. 37:1005-1010. 

Herrick, C. N. 1990. Acidic deposition: an inventory of 

non-federal research, monitoring and assessment 

activity. Washington, DC: National Acid Precipitation 

Assessment Program. 

Hogsett, W. E.; Olszyk, D.; Ormrod, D. P.; Taylor, G. E. Jr.; 

Tingey, D. T. 11987. Air pollution exposure systems 

and experimental protocols: vol I. USEPA Rep. 

EPA/600/3-87/037a. Corvallis, OR: U.S. Environmental 

Protection Agency, Environmental Research Laboratory. 

Kimball, K. D.; Doucette, J. E.; Allen, G. A.; Rancourt, K. 

1989. Monitoring ozone near the Great Gulf and Dry 

River/Presidential Wildernesses: summary report and 

1989 data. Gorham, NH: Appalachian Mountain Club. 

Legge, A. H.; Krupa, S. V., eds. 1990. Acidic deposition: 

sulphur and nitrogen oxides. Boca Raton, FL: Lewis 

Publishers. 

O'Brien, J. T. 1990. Evaluation of ozone damage to 

vegetation on the Lye Brook Wilderness in 1989. 

Surv. Rep. Durham, NH: U.S. Department of Agriculture, 

Forest Service. 

Forest Service Officials Responsible for Class I 

Areas in Region 9 

REGIONAL FORESTER 

USDA Forest Service 

310 W. Wisconsin Avenue 

Milwaukee, Wl 53202 

Staff: Jerome Thomas, 414-297-3659; Harry Parrott, Ext. 3342 

Great Gulf and Presidential-Dry River Wilderness 

FOREST SUPERVISOR 

USDA Forest Service 

White Mountain National Forest 

719 Main Street 

PO Box 638 

Laconia, NH 03247 

Staff: Randy Ferrin, 603-528-8721 

Lye Brook Wilderness 

FOREST SUPERVISOR 

USDA Forest Service 

Green Mountain National Forest 

Federal Building 

PO Box 519 

Rutland, VT 05701-0519 

Staff: Wayne Kingsley, 802-773-0343 

Dolly Sods and Otter Creek Wildernesses 

FOREST SUPERVISOR 

USDA Forest Service 

Monongahela National Forest 

200 Sycamore Street 

Elkins, WV 26241-3962 

Staff: Barry Edgerton, 304-636-1800 

Hercules Glades Wilderness 

FOREST SUPERVISOR 

USDA Forest Service 

Mark Twain National Forest 

401 Fairgrounds Rond 

Rolla, MO 65401 

Staff: Gerald Gott, 314-341-7443 

Rainbow Lakes Wilderness 

FOREST SUPERVISOR 

USDA Forest Service 

Chequamegon National Forest 

1170 4th Avenue South 

Park Falls, Wl 54552 

Staff: Dale Higgins, 715-762-2461 

Boundary Waters Canoe Area Wilderness 

FOREST SUPERVISOR 

USDA Forest Service 

Superior National Forest 

PO Box 338 

Federal Building 

5th Avenue West and 1st Street 

Duluth, MN 55801 

Staff: Robert Berrisford, 218-720-6692 

30 
P.34 

t 

1 

1 

Regional Workshop Attendees 

Dr. Mary Beth Adams 

USDA Forest Service 

Northeastern Forest Experiment Station 

Timber and Watershed Laboratory 

P.O. Box 404 

Parsons, WV 26287 

Professor Harold S. Adams 

Dabney S. Lancaster Community College 

Clifton Forge, VA 24422 

Dr. James Bennett 

National Park Service 

Institute of Environmental Studies 

University of Wisconsin 

1040WARFBIdg. 

610 Walnut Street 

Madison, Wl 53705 

Mr. Robert Berrisford 

USDA Forest Service 

Superior National Forest 

P.O. Box 338 

Duluth, MN 55801 

Mr. Donald Bilyeu 

USDA Forest Service 

Chequemegon National Forest 

1170 4th Avenue South 

Park Falls, Wl 54552 

Mr. Jim Byrne 

USDA Forest Service 

Watershed and Air Management 

P.O. Box 96090 

Washington, DC 20090-6090 

Mr. Gary Carr 

USDA Forest Service 

Androscoggin Ranger District 

White Mountain National Forest 

80 Glen Road 

Gorham, NH 03581 

Mark Cleveland 

USDA Forest Service 

Green Mountain National Forest 

P.O. Box 519 

Rutland, VT 05701-0519 

Dr. Michael Coffman 

Champion International Corporation 

700 Mt. Hope Avenue 

480 Evergreen Woods 

Bangor, ME 04401 

Mr. Jack Craven 

USDA Forest Service 

310 W. Wisconsin Avenue 

Milwaukee, Wl 53203 

Professor Donald D. Davis 

Pennsylvania State University 

Department of Plant Pathology 

Bldg. 211 Buchout Lab. 

University Park, PA 16802 

Mr. Otis Durham 

USDA Forest Service 

White Mountain National Forest 

P.O. Box 638 

Laconia, NH 03247 

Mr. Dewayne Durst 

Air Branch 

USEPA R7726 

Minnesota Avenue 

Kansas City, MO 66101 

Dr. Christopher Eagar 

USDA Forest Service 

Northeastern Forest Experiment Station 

5 Radnor Corporate Center 

100 Matsonford Road 

« Radnor, PA 19087 

Mr. Barry Edgerton 

USDA Forest Service 

Monongahela National Forest 

200 Sycamore Street 

Elkins, WV 26241-3962 

Ms. Pamela Edwards 

USDA Forest Service 

Northeastern Forest Experiment Station 

Timber and Watershed Laboratory 

Box 404 

Parsons, WV 26287 

Dr. C. Anthony Federer 

USDA Forest Service 

Northeastern Forest Experiment Station 

P.O. Box 640 

Durham, NH 03824 

Mr. Randy Ferrin 

USDA Forest Service 

White Mountain National Forest 

P.O. Box 638 

Laconia, NH 03247 

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P.35 

Professor Tom Frost 

Trout Lake Laboratory 

University of Wisconsin 

Rt. 1, Box 7 

Boulder Junction, Wl 54512 

Professor Dave Grigal 

University of Minnesota Dept. Soil Science 

1991 Upper Buford Circle 

St. Paul, MN 55180 

Ms. Charlene Hagedorn 

USDA Forest Service 

Wayne-Hoosier National Forest 

811 Constitution Avenue 

Bedford, IN 47421 

Mr. Lloyd Hendrickson 

USDA Forest Service 

Eastern Region 

310 W. Wisconsin Avenue 

Milwaukee, Wl 53203 

Mr. Mike Herth 

USDA Forest Service 

Monongahela National Forest 

200 Sycamore Street 

Elkins, WV 26241-3962 

Mr. Dale Higgins 

USDA Forest Service 

Chequamegon National Forest 

1170 4th Avenue South 

Park Falls, Wl 54552 

Mr. Robert Hollingsworth 

USDA Forest Service 

Eastern Region 310 W. Wisconsin Avenue 

Milwaukee, Wl 53203 

Ms. Laura Hudnell 

USDA Forest Service 

Chippewa National Forest 

Cass Lake, MN 56633 

Professor Rudolf B. Husar 

Center for Air Pollution Impact and Trend Analysis 

Washington University, Box 1124 

St. Louis, MO 63130 

Mr. William Jackson 

USDA Forest Service 

State & Private Forestry 

180 Canfield Street 

Morgantown, WV 26505 

Dr. Keith Jensen 

USDA Forest Service 

Northeastern Forest Experiment Station 

359 Main Road 

Delaware, OH 43015 

Professor David F. Karnosky 

School of Forestry and Wood Products 

Michigan Technological University 

Houghton, Ml 49931 

Dr. Kenneth D. Kimball 

Appalachian Mountain Club 

Pinkham Notch Camp 

Gorham, NH 03581 

Mr. Don Knauer 

Wisconsin DNR 

Box 7921 

Madison, Wl 53707 

Dr. Robert Kohut 

Boyce Thompson Institute 

Cornell University 

Ithaca, NY 14853 

Mr. Daniel Kucera 

USDA Forest Service 

State & Private Forestry 

5 Radnor Corporate Center 

100 Matsonford Road 

Radnor, PA 19087 

Dr. Allen S. Lefohn 

ASL Associates 

111 N. Last Chance Gulch 

Suite 4A 

Helena, MT 59601 

Dr. Steven E. Lindberg 

Oak Ridge National Laboratory 

P.O. Box 2008, Bldg. 1505 

Oak Ridge, TN 37831 

Dr. Gary Lovett 

Institute of Ecosystem Studies 

Cary Arboretum 

BoxAB 

Millbrook, NY 12545 

Dr. Alan Lucier 

NCASI 

260 Madison Avenue 

New York, NY 10016 

Professor William Manning 

University of Massachusetts 

Dept. of Plant Pathology 

Amherst, MA 01003 

Professor Thomas Markee 

Center for Lake Superior Environmental Studies 

University of Wisconsin - Superior 

Superior, Wl 54880 

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P.36 

Mr. Robert May 

USDA Forest Service 

Mark Twain National Forest 

401 Fairgrounds Road 

Rolla, MO 65401 

Mr. Patrick Merchant 

USDA Forest Service 

Wayne-Hoosier National Forest 

811 Constitution Avenue 

Bedford, IN 47421 

Mr. Richard Poirot 

Air Pollution Control Program 

Vermont Department of Environmental Conservation 

Building 3 South 

103 South Main Street 

Waterbury, VT 05676 

Mr. Charles Spann 

West Virginia Air Pollution Control Commission 

1558 Washington St. East 

Charleston, WV 25311 

Mr. Manfred Milke 

USDA Forest Service 

State & Private Forestry 

1992 Folwell Avenue 

St. Paul, MN 55108 

Dr. Dale S. Nichols 

USDA Forest Service 

North Central Forest Experiment Station 

1831 Highway 169 East 

Grand Rapids, MN 55744 

Mr. James O'Brien 

USDA Forest Service 

State & Private Forestry 

P.O. Box 640 

Durham, NH 03824 

Mr. Harry Parrott 

USDA Forest Service 

310 W. Wisconsin Avenue 

Milwaukee, Wl 53203 

Dr. Donald Porcella 

Environmental Assessment Dept. 

EPRI 

3412 Hillview Avenue 

Palo Alto, CA 94303 

Dr. Jerome Thomas 

USDA Forest Service 

310 W. Wisconsin Avenue 

Milwaukee, Wl 53203 

Dr. E. S. Verry 

USDA Forest Service 

North Central Forest Experiment Station 

1831 Highway 169 East 

Grand Rapids, MN 55744 

Professor Cliff Wetmore 

220 Biological Sciences 

University of Minnesota 

St. Paul, MN 55118 

Mr. William Woodland 

USDA Forest Service 

Monongahela National Forest 

Cheat Ranger District 

Parsons, WV 26287 

Mr. Gaylord Yost 

USDA Forest Service 

Eastern Region (RRWL) 

Federal Plaza, Room 500 

310 W. Wisconsin Avenue 

Milwaukee, Wl 53203 

33