Appendix Y 

Spatial Summary for Uses 

I. Labeled Uses and Associated Land Cover Types for Potassium Nitrate 

and Sodium Nitrate Cartridges 

The following use list is derived from label use information. It is used as a basis for the 

spatial mapping of potassium nitrate and sodium nitrate cartridges. Table 1 shows which 

land cover types are used to represent the spatial area of the use (e.g., the use footprint). 

The land cover classes, were not designed to represent each use specifically but were 

chosen as the best spatial representation of a use area available. For example, dumpster 

use sites are associated with all developed landcover classes, including developed open 

space, since there is a possibility dumpsters can be found there. Greenhouses and 

nurseries are associated with cultivated classes since it is the most likely landcover class 

that can represent those use site areas. 

II. Initial Area of Concern 

After determining uses from label information and obtaining the representative NLCD 

landcover classes, a potential use ‘footprint’ map is made. This includes all areas within 

the state of California where the pesticide could be applied and is shown in Figure 1 for 

potassium nitrate and sodium nitrate cartridges. The footprint of potential use represents 

the chemical’s initial area of concern, and is based on available NLCD land cover data 

and derived map layers. 

Some uses cannot be represented adequately through existing land cover classes, such as 

recreation areas, fencerows or mosquito control sites. The use site for the cartridges is 

associated equally to most land cover classes, and the use pattern can be used in several 

overlapping land cover classes (e.g., the chemical could be used over wide undefined 

geographic areas). In these cases, the initial area of concern is the entire state of 

California. 

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Initial Area of Concern for Potassium Nitrate and Sodium Nitrate Cartridges 

Figure 1 Potential use sites for Potassium Nitrate and Sodium Nitrate Cartridges. 

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A. Land Cover 

Base mapping land cover layers for the initial area of concern analysis were obtained 

from the National Land Cover Dataset (NLCD 2001) for the majority of land use types. 

The NLCD was released as a nationally consistent, regionally indexed dataset in January 

2007. California Gap Analysis Project (GAP) data from the Biogeography Lab from 

UCLA-Santa Barbara (1998) were obtained for the orchard and vineyard uses. These 

raster files were converted to vectors using simplification and majority filter routines and 

merged into NLCD. The turf layer is derived from the NLCD developed areas with the 

impervious surface layer removed. The rights-of-way land cover layer was derived by 

combining road and rail information from TeleAtlas (2007) with U.S. Department of 

Transportation’s National Pipeline Mapping System (1999). Table 2 lists the NLCD and 

derived layers used for initial area of concern representation. 

Table 1 NLCD Layers and its description. 

Layer name Base 

source Description

Cultivated 

Crops

NLCD Grid code 82: Areas used for the production of annual crops, such as corn, 

soybeans, vegetables, tobacco, and orchards/vineyards, and also perennial 

woody crops such as orchards and vineyards. Crop vegetation accounts for 

greater than 20 percent of total vegetation. This class also includes all land 

being actively tilled.

Developed, 

High Intensity

NLCD Grid code 24: Includes highly developed areas where people reside or work in 

high numbers. Examples include apartment complexes, row houses and 

commercial/industrial. Impervious surfaces account for 80 to100 percent of the 

total cover.

Developed, 

Low Intensity

NLCD Grid code 22: Includes areas with a mixture of constructed materials and 

vegetation. Impervious surfaces account for 20-49 percent of total cover. These 

areas most commonly include single-family housing units.

Developed, 

Medium 

Intensity

NLCD Grid code 23: Includes areas with a mixture of constructed materials and 

vegetation. Impervious surfaces account for 50-79 percent of the total cover. 

These areas most commonly include single-family housing units.

Developed, 

Open Space

NLCD Grid code 21: Includes areas with a mixture of some constructed materials, but 

mostly vegetation in the form of lawn grasses. Impervious surfaces account for 

less than 20 percent of total cover. These areas most commonly include largelot single-family housing units, parks, golf courses, and vegetation planted in 

developed settings for recreation, erosion control, or aesthetic purposes.

Forest NLCD Grid codes 41,42,43: Deciduous, evergreen and mixed. Areas dominated by 

trees generally greater than 5 meters tall, and greater than 20% of total 

vegetation cover.

Open Water NLCD Grid code 11: All areas of open water, generally with less than 25% cover of 

vegetation or soil.

Orchards and 

vineyards

CA GAP Grid codes 11210, 11211 and 11212. This is the only CA GAP reference.

Pasture/Hay NLCD Grid code 81: Areas of grasses, legumes, or grass-legume mixtures planted for 

livestock grazing or the production of seed or hay crops, typically on a 

perennial cycle. Pasture/hay vegetation accounts for greater than 20 percent of 

total vegetation.

Wetlands NLCD Grid codes 90, 95: Woody wetlands and emergent herbaceous.

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Base Layer name Description source

Turf NLCD A derived NLCD class based on developed classes and the impervious surface 

layer with corrections applied. 

Rights-of-way US DOT; 

TeleAtlas 

A derived class using road, rail, and pipeline coverages. 

B. Initial Stream Reaches 

In addition to the land cover classes described above, the initial area of concern includes 

the stream segments found within those land cover areas. The stream segments are 

obtained from the NHDPlus dataset. For each stream reach in the hydrography network, 

the data provide a tally of the total area in each NLCD land cover class for the upstream 

cumulative area contributing to the given stream reach. Using the cumulative land cover 

data provided by the NHDPlus (http://www.horizon-systems.com/nhdplus/), a cumulative 

percent cropped area (PCA) is calculated for each stream reach based on the area 

representing all uses for potassium nitrate and sodium nitrate cartridges and is divided by 

the total upstream contribution area. Pesticide exposures in the streams within the initial 

area of concern are conservatively assumed to be represented by the estimated 

environmental concentrations used in RQ calculation. For potassium nitrate and sodium 

nitrate cartridges, no RQs were calculated due to no expected aquatic exposure. 

III. Spatial Extent of the Effects Determination

Based on the results of the lines of evidence for potassium nitrate and sodium nitrate 

cartridges which is independent of spatial analysis, a Likely to Adversely Affect (LAA) 

determination for direct effects and indirect reduction in prey for the CAW and 

modification to critical habitat determination was concluded for the CAW. A Not likely 

to Adversely Affect resulted for the SFGS and SJKF. The spatial extent of the LAA 

effects determination is the area where there is overlap between the area of potential LAA 

effects with critical habitat, habitat, or occurrence sections. This area of potential LAA 

effects includes the initial area of concern for application of potassium nitrate and sodium 

nitrate cartridges on a wide range of land cover types, with no expected spray drift or runoff. Therefore no spray drift buffer or downstream dilution analysis was performed. 

The overlap of land cover corresponding to nitrate cartridges use patterns that result in an 

LAA determination and CAW distribution and/or designated critical habitat for the entire 

state of California is shown in Figures 1. The overlap map provides a depiction of land 

cover that corresponds to nitrate cartridge use patterns, overlapped with the species’ 

range and/or critical habitat. It does not show the spray drift distance or the downstream 

dilution distance e.g., areas in addition to the initial area of concern where LAA direct or 

indirect effects may occur. 

IV. A Note on Limitations and Constraints of Tabular and Geospatial Sources 

The geographic data sets used in this analysis are limited with respect to their accuracy 

and timeliness. The National Land Cover Data Set (Homer 2004) represents the most 

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current and comprehensive collection of national land use and land cover information for 

the United States and represents land cover data obtained between 1994-1998. Three 

additional data sets were used as land cover types to depict use categories not available in 

the NLCD dataset. These supplemental data include orchard and vineyard land cover 

data from the California Gap Analysis Project data (Davis 1998), rights-of-way data 

derived from road and pipeline data from Teleatlas (2007) and the turf layer derived from 

NLCD developed class with corrections applied. 

Hydrographic data are from the NHDPlus data set (http://www.horizonsystems.com/nhdplus/) and the generalized streams and rivers layer from ESRI. 

NHDPlus contains the most current and accurate nationwide representation of hydrologic 

data were also depicted in maps. At a spatial scale of 1:100,000, the NHDPlus might omit 

the smallest streams and water bodies. In addition, in some isolated instances, there are 

errors in the data including missing or disconnected stream segments and incorrect 

assignment of flow direction. 

OPP will continue to endeavor to identify and incorporate (as appropriate) additional land 

cover data sets for other land classes not captured in this assessment. In addition, as new 

updates to existing data occur, these will be evaluated and incorporated as appropriate. 

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References for GIS Maps 

Center for Biological Diversity vs EPA Case No. 07-2794-JCS. 

Davis, F. W., D. M. Stoms, A. D. Hollander, K. A. Thomas, P. A. Stine, D. Odion, M. I. 

Borchert, J. H. Thorne, M. V. Gray, R. E. Walker, K. Warner, and J. Graae. 1998. 

The California Gap Analysis Project--Final Report. University of California, 

Santa Barbara, CA. Available online at 

http://www.biogeog.ucsb.edu/projects/gap/gap_rep.html. Orchard/vineyard layer. 

EPA Environmental Fate and Effects Division NLCD-derived turf from developed and 

impervious layer classes. 

EPA Environmental Fate and Effects Division, rights-of-way layer derived from road, 

rail and pipeline from TeleAtlas (2007) and US DoT (1999). 

ESRI Data and Maps DVD, 2002. (1:24,000). Available online at www.esri.com. 

Homer, C. C. Huang, L. Yang, B. Wylie and M. Coan. 2004. Development of a 2001 

National Land cover Database for the United States. Photogrammetric 

Engineering and Remote Sensing, Vol. 70, No. 7, July 2004, pp. 829-840. 

Available online at http://www.mrlc.gov/pdf/July_PERS.pdf. NLCD layers. 

Sacramento San-Joaquin Delta Fact Sheet. California Department of Water Resources. 

Available online at http://www.water.ca.gov/deltainit/docs/factsheet.pdf. 

Simley, J.D., Carswell Jr., W.J., 2009, The National Map—Hydrography: U.S. 

Geological Survey Fact Sheet 2009-3054, 4 p. Available online at nhd.usgs.gov. 

TeleAtlas. 2007. “Dynamap 2000.” Version No. 17.1. Released April 2007. USPS 

Current to February 2007. 

U.S. Department of Transportation’s National Pipeline Mapping System. 1999. 

USDoT/Baker. Office of Pipeline Safety, Washington, D.C. 03/30/1999. 

Available online at www.npms.rspa.dot.gov. 

U.S. Fish and Wildlife Service (USFWS). Critical habitat maps (Delta Smelt, Calif. 

Tiger Salamander, Valley Elderberry Longhorn Beetle, Bay Checkerspot 

Butterfly, Alameda Whipsnake, Tidewater Goby). Available online at 

http://criticalhabitat.fws.gov. (Accessed 24 September 2009). 

SF Garter Snake 

U.S. Fish and Wildlife Service (USFWS), 1985. Recovery Plan for the San Francisco 

Garter Snake (Thamnophis Sirtalis Tetrataenia). U.S. Fish and Wildlife Service, 

Portland, Oregon. 77pp. Available online at 

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- 7 - 

http://ecos.fws.gov/docs/recovery_plan/850911.pdf. (Accessed 24 November 

2009). 

San Joaquin Kit Fox 

U.S. Fish and Wildlife Service (USFWS), 1998. Recovery Plan for upland species of the 

San Joaquin Valley, California. Region 1, Portland, OR. 319 pp. Available online 

at http://ecos.fws.gov/docs/recovery_plan/980930a.pdf. (Accessed 24 November 

2009 for the San Joaquin Kit Fox).