Bureau of Land Management

Abandoned Mine Lands Program

Feasibility Study for AML Inventory

Validation and Physical Safety Closures

July 2013 
U.S. Department of the Interior 

Mission

The U.S. Department of the Interior protects America’s natural resources and heritage, honors our 

cultures and tribal communities, and supplies the energy to power our future.

Bureau of Land Management 

Mission

It is the mission of the Bureau of Land Management to sustain the health, diversity, and productivity 

of the public lands for the use and enjoyment of present and future generations.

Editing, design, and layout by the BLM National Operations Center.
Bureau of Land Management

Abandoned Mine Lands Program

Feasibility Study for AML Inventory

Validation and Physical Safety Closures

July 2013 

BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures iii

Contents

Executive Summary ..................................................................................................................... 1

1. Background and Purpose ...................................................................................................... 3

1.1 The BLM’s Progress in Inventorying and Remediating AML Physical Safety Hazards....... 3

1.2 Government Interest in the BLM’s AML Program ........................................................... 4

1.3 Purpose of This Feasibility Study ...................................................................................... 4

1.4 Activities Covered by This Feasibility Study...................................................................... 4

2. Methodology and Results...................................................................................................... 7

2.1 Developing a Working Inventory of Physical Safety Hazard Sites..................................... 7

2.2 Prioritizing Sites Based on Location with Respect to Population/Recreation Areas ........... 8

2.3 Estimating BLM State Office–specific Average Remediation Costs................................... 9

3. Estimated Total National Field Validation and Remediation Costs ................................... 17

4. Conclusions ......................................................................................................................... 21

Appendix A, Proximity Analysis Data Source Definitions....................................................... 23

Tables

Table 1 AML Physical Safety Hazard Sites (by BLM State Office and by Level of Priority)....... 9

Table 2 AML Program Elements, Codes, and Workload Measures ......................................... 10

Table 3 AML Program Elements: Site Inventory and Remediation ........................................ 11

Table 4 Total AML Physical Safety Hazard Sites Inventoried and Remediated (Nationwide), 

 FY 2006–2010......................................................................................................... 12

Table 5 Number and Average Cost of Inventorying and Remediating Physical Safety

Hazards (by BLM State Office), FY 2006–2010 ........................................................ 13

Table 6 Estimated Future Average Cost per Site for Field Validation and Remediation of AML

 Physical Safety Hazards (by BLM State Office) ........................................................ 15

Table 7 Estimated Future Cost To Field-Validate and Remediate AML Physical Safety Hazard 

Sites (by BLM State Office and by Level of Priority) .................................................. 18

Table 8 Estimated Future Cost To Field-Validate and Remediate AML Physical Safety Hazard 

Sites (by BLM State Office)........................................................................................ 19

BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 1

Executive Summary

The Abandoned Mine Lands (AML) Program of the U.S. Department of the Interior (DOI), 

Bureau of Land Management (BLM), operates under multiple authorities. Assumptions in 

this study are based on a continuation of the $15.9 million appropriated in Fiscal Year 2010. 

Appropriations are used to identify and remediate both physical safety and environmental 

hazards associated with abandoned hardrock mines on or affecting public lands. The BLM uses 

appropriations from general revenues for a range of activities, including:

•	 AML site validation (for example, site inventory, validation characterization, and maintenance of

an inventory database)

•	 cultural, historical, and wildlife studies required under the National Environmental Policy

Act (NEPA) or Comprehensive Environmental Response, Compensation, and Liability Act 

(CERCLA)

•	 remedy design and construction

•	 remediation of physical safety and environmental hazards

•	 monitoring and maintenance

In 2009 the U.S. Senate Committee on Appropriations directed the DOI Secretary to provide a 

report on the status of the inventory and to submit a completed inventory for review.1 In addition, 

the Government Accountability Office (GAO) reported and testified about the wide variation in 

estimates of abandoned hardrock mines owing to the lack of a generally accepted definition for 

a hardrock mine site among state and federal agencies in the West.2 Also, the DOI’s Office of 

Inspector General (OIG) has issued several reports concerning AML programs and sites. These 

reports made findings and recommended that the BLM: 

•	 assess its lands to identify hazardous sites in close proximity to populated places

•	 inspect these sites and take appropriate action to mitigate safety hazards

•	 validate existing inventory data and develop procedures for ongoing data collection to ensure that

data in the inventory is complete, accurate, and consistent3

1Senate Report 111-038 – Department of the Interior, Environment, and Related Agencies, Appropriations Bill, 2010. 

2“Hardrock Mining: Information on Abandoned Mines and Value and Coverage of Financial Assurances on BLM Land,” 

GAO-08-574T, March 12, 2008.

3OIG Flash Report C-IN-BLM-0013-2005, “Public Safety Issues at the Saginaw Hill Property, Bureau of Land 

Management,” U.S. Department of the Interior, Office of Inspector General, March 2005; and Audit Report C-INMOA-0004-2007, “Abandoned Mine Lands in the Department of the Interior,” U.S. Department of the Interior, Office 

of Inspector General, July 2008.
2 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

The BLM is committed to taking the necessary steps 

to define the full extent of the problem associated with

known abandoned mine hazards. In response to the 

above critiques, the BLM has prepared this “Feasibility

Study for AML Inventory Validation and Physical 

Safety Closures” to estimate the costs to validate and 

address the unremediated AML sites posing physical 

safety hazards. 

This study determined that the total cost to complete 

field validation and physical safety hazard remediation 

at the 22,104 known AML physical safety sites is 

approximately $402.6 million (Table 8). The BLM

estimates that it will: 

•	 cost $39.7 million to field-validate all of the AML

sites with physical safety hazards that are a part of 

the working inventory

•	 cost $362.9 million to remediate all of the AML sites

with physical safety hazards that are a part of the 

working inventory

To address the working inventory of sites with physical 

safety hazards most effectively, the BLM must set 

priorities. Consistent with existing priority criteria, the

BLM has identified the following high- , medium- , and 

low-priority sites based on proximity to populated places:

•	 594 high-priority sites (sites within a quarter mile of

a populated place or school currently in use) 

•	 647 medium-priority sites (sites that are within

a quarter mile of a historic populated place [for

example, a mining “ghost town”], historic school, or

area of high visitation)

•	 20,863 low-priority sites (sites located more than a

quarter mile away from a populated place)

The BLM estimates that $11.4 million is needed to 

field-validate and remediate all high-priority sites 

impacting public safety and that $12.6 million is 

required to field-validate and remediate the mediumpriority sites; approximately $377.7 million is needed

to field-validate and remediate those sites characterized 

as low priority (Table 7).
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 3

1. Background and Purpose

The Abandoned Mine Lands (AML) Program of the U.S. Department of the Interior (DOI), Bureau 

of Land Management (BLM), is responsible for addressing two broad categories of hazards associated 

with abandoned hardrock mines4: physical safety hazards, such as open adits (horizontal openings), 

open shafts (vertical openings), highwalls, and pits; and environmental hazards, such as heavy metals 

in mine wastes and mill tailings and acid mine drainage that, when exposed to air and water, can

impact water quality and human health. BLM tracks and addresses:

•	 sites that pose solely physical safety hazards

•	 sites that pose solely environmental hazards

•	 sites that pose both physical safety and environmental hazards

1.1 The BLM’s Progress in Inventorying and Remediating AML 

Physical Safety Hazards

Since the BLM’s AML Program was established in the late 1990s, the BLM has made great strides 

in identifying and addressing abandoned mine sites and associated physical safety hazards. The 

BLM developed the Abandoned Mine Site Cleanup Module (AMSCM) to track information about 

abandoned mine sites. The BLM prioritizes and remediates hazards at abandoned mine sites using 

a risk-based approach. It is an enormous task that will take the continued, dedicated commitment 

of resources over an extended period of time and cooperation with federal, state, local, and tribal

governments as well as nongovernmental partners. Meanwhile, the risks associated with abandoned 

mines remain and continue to increase because more and more remote areas are being developed 

or accessed for recreation. Even dangerous mines that have been properly sealed off are sometimes 

entered, vandalized, and left open, potentially subjecting anyone nearby to unexpected and

serious dangers.

The BLM remains focused on identifying AML sites with physical safety hazards, in particular, 

and on ensuring that immediate temporary or permanent mitigation measures are implemented as 

appropriate to address those sites posing the greatest threat to public safety. In fiscal years 

4The BLM’s Abandoned Mine Land Program Policy, MS-3720, defines an abandoned mine as follows: “An abandoned hard 

rock mine on, or affecting public lands administered by BLM, at which exploration, development, mining, reclamation,

maintenance, and inspection of facilities and equipment, and other operations ceased as of January 1, 1981 (the effective

date of BLM’s Surface Management regulations codified at 43 CFR 3809) with no evidence demonstrating that the miner 

intends to resume mining. For many abandoned mines, no current claimant of record or viable potentially responsible party 

exists. Abandoned mines generally include a range of mining impacts or features that may pose a threat to water quality,

public safety, and/or the environment.” 
4 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

(FY) 2006–2009 the BLM completed inventory 

activities at 5,481 AML sites, and remediated physical 

safety hazards at 1,733 sites.5 Where possible, the 

BLM conducted mitigation actions during the initial 

site visit. BLM state offices have increased inventory 

efforts in recent years to ensure that tangible and 

accurate information is gathered to address the full 

scope and scale of the problem as the AML Program 

moves forward. Although the BLM’s inventory is far 

from complete and AML sites continue to be identified, 

it is important to emphasize that many of the sites with 

the highest potential for harm to public health and 

safety have already been identified by federal, state, 

local, and tribal partners and are being addressed.

1.2 Government Interest in the BLM’s 

AML Program

In recent years there has been considerable government 

interest at the national level in the BLM’s AML 

Program and in sites posing physical safety hazards. For 

example:

•	 The Government Accountability Office (GAO)

reported and testified about the wide variation in 

estimates of abandoned hardrock mines owing to 

the lack of a generally accepted definition for a 

hardrock mine site among state and federal agencies 

in the West. See, “Hardrock Mining: Information 

on Abandoned Mines and Value and Coverage of 

Financial Assurances on BLM Land,” GAO-08-574T, 

March 12, 2008.

•	 The Department of the Interior’s Office of Inspector

General (OIG) has issued several reports concerning 

AML programs and sites. In 2008 the Inspector 

General (IG) stated that the “BLM’s inventory was 

incomplete, inaccurate and inconsistent.” The IG 

found that much of the data in the inventory was 

derived from the U.S. Bureau of Mines before its 

closure in 1996 and was never validated by field 

surveys. These reports recommended that the 

BLM assess its lands to identify hazardous sites in 

close proximity to populated places; inspect these

sites and take appropriate action to mitigate safety 

hazards; and validate existing inventory data and

develop procedures for ongoing data collection 

to ensure that data in the inventory are complete, 

accurate, and consistent. See, OIG Flash Report 

C-IN-BLM-0013-2005, “Public Safety Issues 

at the Saginaw Hill Property, Bureau of Land 

Management,” March 2005; and Audit Report C-INMOA-0004-2007, “Abandoned Mine Lands in the 

Department of the Interior,” July 2008.

1.3 Purpose of This Feasibility Study

Given the increasing urgency of remediating AML 

physical safety hazards, in particular, this feasibility 

study focuses on the total cost of field-validating and 

remediating all such sites (as described in the AMSCM 

inventory). It does not, therefore, include estimated 

costs posed by environmental hazards, either in whole 

or in part.

1.4 Activities Covered by This 

Feasibility Study

Two primary categories of activities are required to

address AML physical safety sites: site field validation

and remediation of physical safety hazards. 

Throughout this study, unless otherwise specified, 

the term “remediation” means taking one or more 

permanent measures to eliminate a hazard.

Field Validation of AML Sites

Once a site is identified as a potential AML site, it must 

be field-validated to determine whether the site is eligible 

for funding under the AML Program.6 BLM state 

offices and field offices make this determination by:

5Management Information System (MIS), Bureau of Land Management.

6In general, an abandoned mine site is eligible for funding under the BLM’s AML program if the site: is on or affecting land administered 

by the BLM; was last mined before promulgation of the 43 CFR 3809 regulations (that is, before January 1, 1981), which implement the 

unnecessary or undue degradation provision of the Federal Land Policy and Management Act of 1976 (43 U.S.C. 1701, et seq.); and has no

mining claimants or responsible parties able or willing to clean up the site.
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 5

•	 conducting research to determine land status and

ownership and the extent of field activity needed,

which includes preparing and conducting site visits 

to collect on-the-ground data and information related 

to the AML site

•	 reporting and filing information in the BLM’s

AMSCM database, which stores information about 

the sites and their associated features

In addition to conducting these basic informationgathering activities during field validation, field 

personnel also collect information to determine the best 

approach for addressing the physical safety hazards at the 

site. In some cases, a temporary action, such as posting 

of warning signs and construction of fencing to control 

access, may be implemented to reduce physical safety 

hazards until a permanent remedy can be put in place. 

Remediation of Physical Safety Hazards

Permanent remediation of a physical safety hazard site 

may include such measures as: 

•	 closing adits and shafts to keep people out while

protecting bat habitat

•	 filling or blocking other potentially hazardous

openings

•	 backfilling

•	 draining impoundments

•	 removing leftover equipment, dangerous structures,

and debris

As described earlier, any temporary measures to address 

a physical safety hazard site are considered part of field 

validation activities, not remediation.

BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 7

2. Methodology and Results

The four activities described below explain the methodology and data assumptions underlying this

feasibility study: 

•	 developing a working inventory of physical safety sites

•	 prioritizing the sites based on location with respect to population/recreation areas

•	 estimating BLM state office–specific average remediation costs

•	 estimating the total national remediation cost

2.1 Developing a Working Inventory of Physical Safety 

Hazard Sites 

AMSCM is the AML Program’s database system of record for tracking the inventory of AML sites. 

It stores and reports information related to abandoned mine sites. The data contained in AMSCM 

assist AML Program managers in controlling:

•	 overall remaining workload estimates of sites, features, and feature types

•	 the status of sites under the National Environmental Policy Act (NEPA) or Comprehensive

Environmental Response, Compensation, and Liability Act (CERCLA) processes

•	 future monitoring and maintenance requirements and schedules for visiting remediated sites

•	 data and statistics useful for strategic and operational planning

As of November 2, 2010, AMSCM had tracked a total 29,090 AML sites with environmental 

and/or physical safety hazards. Each record comprises a site located on or potentially affecting surfaces 

managed by the BLM. Each site may have one or more features associated with it that require

remediation. 

To refine further the universe of sites for purposes of this feasibility study, AMSCM was queried

to identify AML sites with only physical safety hazards. In other words, sites that pose solely 

environmental hazards and sites that pose both environmental hazards and physical safety hazards 

were removed from consideration. Also excluded from the analysis were sites at which remediation

actions had been completed or were ongoing. Thus, a total of 2,825 sites were excluded from the

analysis in this feasibility study. As reflected in Table 1, there are 22,104 AML sites with solely 

physical safety hazards in 11 BLM state offices. These sites represent the working inventory of 

AML sites with physical safety hazards that must be addressed.
8 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

2.2 Prioritizing Sites Based on 

Location with Respect to

Population/Recreation Areas

This feasibility study determined which sites posed the 

highest risk in terms of physical safety hazards based on 

the AML Program’s risk-based approach to addressing 

AML sites and the AML Program’s National Evaluation 

Criteria (see Abandoned Mine Land Program Policy 

Handbook, H-3720-1). In addition, as a result of the 

OIG’s Saginaw Hill Flash Report, the BLM AML 

Program identified priority AML sites to be addressed 

that are within a quarter mile of populated places. This

study uses the quarter-mile criteria to identify high- ,

medium- , and low-priority sites based on their relative 

proximity to population centers and schools.

BLM policy directs state offices and field offices to 

conduct site validation on and mitigate AML-related 

safety hazards at those sites in proximity to populated

places (PPL). The term PPL is a U.S. Geological Survey 

designation for a city, town, or village, and the primary 

point of a PPL is the center of original place, such as 

the city or town hall, main post office, or town square,

regardless of changes over time. Sites located near PPLs 

or recreation areas have a higher likelihood of being 

easily accessed by the public. 

As a first step in identifying the proximity of AML

physical safety hazard sites to PPLs, latitude and 

longitude coordinates for each site were obtained from 

the AMSCM working inventory data and plotted in 

a Geographic Information System (GIS). A buffer 

was created around each site using AMSCM assigned 

acreage, if available, to approximate the site’s size. If

AMSCM did not contain an acreage value for a site, a 

minimum buffer size of 1 acre was applied. 

Data were compiled from several sources to identify 

PPLs and other areas where people are likely to live, 

gather, and/or recreate, including:

•	 U.S. Geological Survey — Geographic Names

Information System (GNIS)7:

≈ populated places

≈ parks

≈ schools

•	 Federal Emergency Management Agency — HAZUS

MH database:

≈ schools

•	 BLM spatial data for:

≈ recreation sites

≈ buildings

≈ campgrounds

≈ trailheads 

A more detailed description of these data sets is 

provided in Appendix A.

The AML physical safety hazard sites were plotted in 

a GIS mapping system, and the distance of each site 

to potential population sources was calculated. The 

buffered site locations were then analyzed for proximity

to populated places, using the following criteria to 

prioritize the sites: 

•	 High priority: PPL or schools within a quarter mile

of one or more AML sites

•	 Medium priority: historic mining towns, historic 

7U.S. Geological Survey, 19810501, “U.S. Geographic Names Information System (GNIS),” All States_20101001.zip, Reston, Virginia, 

October 2010. http://geonames.usgs.gov/domestic/index.html.
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 9

schools, recreation areas, parks, camps, or trails 

within a quarter mile of one or more AML sites

•	 Low priority: sites located more than a quarter mile

away from a populated place

The BLM will continue to focus on addressing highand medium-priority sites to ensure protection of 

public safety; however, it is important to note that 

injuries have occurred at low-priority sites and that 

these sites must also be remediated. Low-priority 

sites are becoming more accessible to the public as 

population increases, causing urbanization to encroach 

on once remote areas. As this occurs, low-priority sites 

may shift to a higher priority for the BLM. The BLM 

will track low-priority sites and remediate hazards as 

appropriate.

Table 1 shows the number of high- , medium- , and 

low-priority sites on or affecting lands managed by 

each BLM state office. There are 594 high-priority 

sites, or 2.6 percent of the physical safety hazard sites 

tracked in AMSCM. There are 647 medium-priority 

sites, or 2.9 percent of the physical safety hazard sites 

tracked in AMSCM.8 

Table 1. AML Physical Safety Hazard Sites 

(by BLM State Office and by Level of Priority)

BLM State Office High Priority Medium Priority Low Priority

Working Inventory 

(Total AMSCM Physical 

Safety Sites)

Alaska 0 1 158 159

Arizona 70 27 2,776 2,873

California 66 66 977 1,109

Colorado 16 41 957 1,014

Idaho 2 4 152 158

Montana/South Dakota 18 32 727 777

Nevada 293 393 9,962 10,648

New Mexico/Texas 107 9 1,378 1,494

Oregon/Washington 6 1 288 295

Utah 13 69 2,800 2,882

Wyoming 3 4 688 695

Total 594 647 20,863 22,104

8Some sites are located proximate to more than one populated place, and the GIS analysis identified 59 sites that qualified for multiple

priorities. For each of these sites, the highest level of priority for which the site qualified was assigned to that site.

2.3 Estimating BLM State Office– 

specific Average Remediation

Costs

To estimate the total cost to field-validate and 

remediate the BLM’s physical safety hazard 

sites, this study analyzed expenditure and

performance data for FYs 2006–2010 from the 

BLM Management Information System (MIS) and 

Performance Management System (PMS) to develop 

an estimate of BLM state office–specific average 

remediation costs, as described in the remainder of 

this section.
10 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

Data Sources for Estimating Cost of 

AML Activities

The AML Program’s business processes are managed 

by the BLM’s MIS and its several modules (Budget 

Planning System, Performance Module, and ActivityBased Costing Reports). MIS monitors direct costs for 

tracked activities, in addition to the Bureau Full Cost 

(BFC), which includes direct costs plus administrative 

costs distributed across all program elements.9 The 

BLM uses the MIS to establish annual performance 

targets and track actual accomplishments throughout 

the year. MIS represents the best available data source 

for tracking historical costs associated with field 

validation and remediation of physical safety hazards at 

the national level.

Workload measures established by the BLM (for 

example, number of AML sites, number of acres

treated) are used to track program accomplishments. 

The BLM uses six program elements in the MIS

and PMS to measure field performance in the AML 

Program, as described in Table 2.

Table 2. AML Program Elements, Codes, and Workload Measures

AML Program Element PE Code Workload Measure

Inventory AML sites BH Number of AML sites

Remediate AML physical safety hazards HP Number of AML sites

Implement AML projects to restore water quality JK Number of acres treated

Monitor and maintain AML, hazmat, and Natural 

Resources Damage Assessment and Restoration 

(NRDAR) sites (sites where cleanup actions are 

completed)

MG

Number of AML sites

Evaluate potentially responsible parties (PRPs) for cost 

avoidance/recovery

NP Number of PRP searches 

completed

Process hazmat cost avoidance/recovery cases NQ Number of cases referred to 

DOI Solicitor

9A “program element” is a specific activity or product for which the BLM captures cost data.

The first two program elements listed are of concern 

in this feasibility study, as they directly correlate to the 

cost of field validation and remediation of physical 

safety hazards. Table 3 describes the nature of the work 

included within these two performance elements and 

the costs involved.
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 11

Table 3. AML Program Elements: Site Inventory and Remediation

Program Element BH — Inventory AML Sites:

Description: Inventory work at specific AML sites or at areas where AMLs may exist. Estimate the number of sites 

planned for inventory and use that estimate for the planning target. 

Workload Measure: Number of sites inventoried or physical safety hazards mitigated (for example, through 

temporary measures, such as fencing or signs). 

Costs Included:

•	 labor and operations for inventory (including field equipment, travel, and training)

•	 mitigation (temporary remediation measures, such as the placing of warning signs, protective fencing, or other

temporary measures restricting access)

•	 other costs: cadastral surveys, GIS and data management support, consultations with Indian tribes/Alaska

Native corporations, outreach and environmental education

Program Element HP — Remediate Physical Safety Hazards: 

Description: Remediate physical safety hazards at AML sites, including:

•	 closures of adits and shafts

•	 backfilling of highwalls

•	 drainage of impoundments

•	 removal of leftover equipment and debris

•	 revegetation to help offset erosion and improve land stability

Workload Measure: Number of sites remediated. Mitigation (temporary remediation measures) is not a unit of 

accomplishment for HP and should be reported under BH.

Costs Included:

•	 labor and operations (including travel, materials, and contracts)

•	 other costs: cadastral surveys, GIS and data management support, consultations with Indian tribes/Alaska

Native corporations, outreach and environmental education
12 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

Cost estimation for this feasibility study uses MIS data 

for the BH and HP program elements for each BLM 

state office for FY 2006–2010. MIS data related to cost 

and workload measures (the number of sites addressed 

by site inventory and remediation activities) during 

this period were reviewed for consistency, patterns and 

trends, and potential outlier data. 

This study compared trends in the MIS data during 

FY 2006–2010 with AMSCM data over the same 

period to analyze the relationship between cost 

and performance for field validation and physical 

safety hazard remediation activities. This analysis 

assessed the accuracy and viability of historical 

MIS data as a basis for forecasting the future cost 

and timeframes for completing the inventory and 

remediation of AML sites. This comparison found 

that the distribution of the number and type of 

sites addressed at the state office level was generally 

consistent with the number and type of physical 

safety sites in the working inventory. Thus, it was 

determined that the MIS data could reasonably 

be used as a method of projecting future costs for 

addressing physical safety hazards.

While detailed information on AML site features and 

hazard remediation activities is tracked in AMSCM, 

MIS captures costs only at the site level, making it 

possible to conduct only a site-wide assessment of cost 

and activities. Although measuring performance at 

the site level is not as granular as measuring costs per 

feature type or costs per type of remediation activities at 

a single feature, the business process of inventory/field 

validation and remediation activities is normally done 

either for the entire site or for a group of sites.

BLM Total Historical Remediation Costs, 

FY 2006–2010

The total Bureau Full Cost (BFC) for the BLM’s 

inventory and remediation of physical safety hazard 

sites during FY 2006–2010 was $75.8 million. 

Distinguishing between the two program elements, site 

inventory activities (BH) accounted for approximately

$24.0 million, with a national average cost per site of 

approximately $2,300 across the 5-year period, and

remediation of physical safety hazards (HP) accounted 

for approximately $51.8 million, with a national

average cost per site of approximately $17,400 across

the 5-year period, as shown in Table 4.

Table 4. Total AML Physical Safety Hazard Sites 

Inventoried and Remediated (Nationwide), FY 2006–2010 

Year

BH: Inventory AML Sites HP: Remediate Physical Safety Hazards

Sites Cost

Average Cost 

per Site 

(= Sites/Cost)

Sites Cost

Average Cost 

per Site

(=Sites/Cost)

2006 1,077 $ 2,077,300 305 $ 3,691,700

2007 1,378 2,385,900 509 2,834,200

2008 1,032 1,932,000 474 8,315,200

2009 2,005 5,073,100 474 16,397,400

2010 5,037 12,484,800 1,217 20,570,500

2006–2010 10,529 $23,953,100 $2,300 2,979 $51,809,000 $17,400
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 13

BLM State Office–specific Historical 

Remediation Costs, FY 2006–2010

There is significant variability in the number, type, 

accessibility, and approach to field validation and 

remediation across BLM state offices. In addition, 

the number of high- , medium- , and low-priority 

sites is distributed unevenly across BLM state offices. 

Therefore, this feasibility study found it appropriate to 

apply the average cost for each BLM state office (rather 

than the national average) to future field validation and 

remediation activities. 

Table 5 shows the average cost of inventory and 

remediation for each BLM state office for FY 2006–

2010, based on MIS data. The variability in the average 

cost per site in different states reflects the variability of 

how the state office programs function, and the number 

and type of sites that each state office addresses.

Table 5. Number and Average Cost of Inventorying and Remediating AML 

Physical Safety Hazards (by BLM State Office), FY 2006–2010 

State

BH: Inventory AML Sites HP: Remediate Physical Safety Hazards

Sites Cost 

Average 

Cost per Site 

(=Sites/Cost)

Sites Cost

Average 

Cost per Site 

(=Sites/Cost)

Alaska 5 $ 2,027,500 $ 405,500 1 $ 38,000 $ 38,000 

Arizona 1,337 2,087,100 1,600 468 3,064,900 6,500 

California 1,598 8,305,800 5,200 745 14,456,300 19,400 

Colorado 229 469,300 2,000 246 2,495,400 10,100 

Idaho 126 1,942,200 15,400 157 2,090,500 13,300 

Montana/

South Dakota 465 1,625,100 3,500 176 5,223,000 29,700 

Nevada 4,000 4,204,500 1,100 777 16,070,400 20,700

New Mexico/

Texas 1,419 598,200 400 110 1,153,400 10,500

Oregon/

Washington 581 687,300 1,200 51 2,517,300 49,400 

Utah 756 1,351,700 1,800 235 1,685,100 7,200 

Wyoming 13 654,300 50,300 13 3,014,700 231,900 

Bureau-wide 10,529 $23,953,000 $ 2,300 2,979 $51,809,000 $ 17,400
14 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

The BLM Washington Office and state office program 

leads (SOPLs) analyzed the data presented in Table 5 

to authenticate the average cost per site across the BLM 

and to understand better the variability in average cost 

per site across BLM state offices. In general, for BLM 

state offices that had average per site BH and/or HP 

costs that were lower than the national average, SOPLs 

cited the following reasons:

•	 economies of scale by addressing multiple sites and

safety hazards simultaneously

•	 larger corps of AML Program employees and

volunteers

•	 partnership with universities and nonprofit

organizations

•	 initial remediation of easily accessible sites

In general, for BLM state offices that had average per 

site BH and/or HP costs that were higher than the 

national average, SOPLs cited the following reasons:

•	 sites that are remote or spread out across the state,

requiring additional resources for mobilization/

demobilization

•	 state- or region-specific requirements impacting

design of hazard remediation (for example, closing a

safety hazard in remote Alaska requires transporting

construction material by air or barge, while a safety 

closure in remote California could very likely be 

reached by land)

•	 a small number of costly sites

Further, the BLM’s Alaska State Office reported BH and 

HP data on a limited number of sites during FY 2006–

2010, skewing average costs. Owing to limited data and 

the fact that remote locations and regional requirements

result in significantly higher mobilization/demobilization, 

this feasibility study uses the national average with a 

5x mobilization/demobilization factor (see Table 6).

Estimated Future BLM State Office–specific 

Remediation Costs 

At the BLM state office level, the historical average cost per 

site for inventory and hazard remediation in the MIS is a 

starting point for estimating the future cost of addressing 

the remaining high- and medium-priority sites. The BLM 

Washington Office and SOPLs reviewed the MIS data 

to confirm that it was appropriate to apply the historical 

average state office–specific remediation cost to future 

remediation activities. For most state offices, the historical 

average BH and HP cost per site was determined to be the 

best estimate of future costs. However, for other state offices 

(for example, those with very little data recorded in MIS,

or with unusual geographic considerations), an alternative 

average BH and HP cost per site was determined to be 

more appropriate, as described in Table 6. 
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 15

Table 6. Estimated Future Average Cost per Site for Field Validation and 

Remediation of AML Physical Safety Hazards (by BLM State Office)

BLM State 

Office

Estimated Future 

Average Cost per Site

Field Data Source and Rationale

Validation 

(BH)

Remediation 

of Physical 

Safety 

Hazards 

(HP)

Alaska $ 11,400 $ 87,000 MIS national average for BH and HP (FY 2006–2010) was 

used, owing to the low number of sites that were reported in MIS 

during that period. As supported by BLM state office data, a 5x 

mobilization/demobilization factor was applied to the MIS national 

average cost per site to account for the remote location of most sites.

Arizona 1,600 6,500 MIS state office average for BH and HP (FY 2006–2010).

California 5,200 19,400 MIS state office average for BH and HP (FY 2006–2010).

Colorado 2,000 10,100 MIS state office average for BH and HP (FY 2006–2010). 

Idaho 15,400 13,300 MIS state office average for BH and HP (FY 2006–2010). Field 

validation cost is higher than remediation cost because some 

activities that are typically categorized in MIS as remediation are 

categorized as field validation in Idaho.

Montana/

South Dakota

3,500 15,600 MIS state office average for BH (FY 2006–2010) was used for field 

validation. The MIS state office HP data included a $2.5 million 

project funded by the American Recovery and Reinvestment Act of 

2009. This was a unique occurrence in FY 2010, which artificially 

increased the average cost per site for remediation to well above the 

national average. Consequently, this project was removed from the 

MIS data, and the average HP cost per site was calculated to be 

$15,600 (FY 2006–2010).

Nevada 1,100 20,700 MIS state office average for BH and HP (FY 2006–2010).
16 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

Table 6. Estimated Future Average Cost per Site for Field Validation and 

Remediation of AML Physical Safety Hazards (by BLM State Office)

BLM State 

Office

Estimated Future 

Average Cost per Site

Data Source and Rationale

Field 

Validation 

(BH)

Remediation 

of Physical 

Safety 

Hazards 

(HP)

New 

Mexico/

Texas

800 17,400 The BLM’s New Mexico State Office recently launched and has 

been conducting field validation and remediation in high-volume 

locations, depressing the average costs per site. The MIS state office 

data were deemed insufficient to determine an average cost per site 

for the purpose of estimating field validation (BH) costs, and the MIS 

national average cost per site was found to be too high. The BLM’s 

Washington Office and New Mexico State Office determined that 

$800 was an appropriate estimate for future field validation activities 

based on state office data. The MIS national average (FY 2006–

2010) was found to be appropriate for estimating future HP costs.

Oregon/

Washington

2,300 17,400 The MIS state average for BH (FY 2006–2010) was not used, 

because the historical state average cost per site was determined to 

be too low relative to future expected costs in Oregon. For the last 

several years, state office staff have been working on sites with good 

access; future inventory work is anticipated to be in more remote 

locations, with a higher cost that is similar to the national average. 

The bureau-wide national average was used instead of the state 

average cost.

The MIS state average for HP was not used because the historical 

state average cost per site was determined to be too high relative 

to projected costs for remediation of physical safety hazards. 

Future physical safety remediation programs will address multiple 

projects at the same time, and this will result in lower costs per site 

than previously incurred on a statewide average. The bureau-wide 

national average was used instead of the state average cost.

Utah 1,800 7,200 MIS state office average for BH and HP (FY 2006–2010).

Wyoming 2,300 17,400 The MIS state average for BH and HP (FY 2006–2010) was not 

used, because historical data captured in MIS do not fully reflect state 

office activities. The BLM national averages were used.
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 17

3. Estimated Total National Field 

Validation and Remediation Costs

In FY 2010 the BLM was appropriated $15.9 million for the AML Program; however, only a 

portion of the annual appropriation is normally available for AML site inventory and remediation of 

physical safety hazards (that is, BH and HP activities), with the rest mostly targeted to fund priority 

environmental AML projects. Based on an annual appropriation of $15.9 million, the BLM assumes, 

for purposes of this study, that 20 percent of the annual appropriation will be available to fund field 

validation (BH) each fiscal year, and that 30 percent of the annual appropriation will be available to 

fund remediation of physical safety hazards (HP) each fiscal year. Assuming that the program will 

continue to receive an annual appropriation of $15.9 million, 20 percent or $3.2 million will be 

available for BH activities, and 30 percent or $4.8 million will be available for HP activities. 

An estimated future cost of completing field validation and remediation of the sites in the AMSCM 

database, as ranked by state and priority, is approximately $402 million (see Table 7). Cost estimates

are based on the number of sites in the working inventory for each state office (see Table 1), as 

prioritized in the proximity analysis, and multiplied by the estimated per-site cost of field validation

(BH) and physical safety hazard remediation (HP) in Table 6. Minor cost estimate differences 

between Table 7 and Table 8 are attributable to averaging; Table 7 differentiates costs by priority, 

whereas Table 8 averages costs with no consideration given to priority.
18 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

Table 7. Estimated Future Cost To Field-Validate and Remediate

 AML Physical Safety Hazard Sites (by BLM State Office and by Level of Priority)

BLM State 

Office

Number of AML Physical Safety Sites 

in Working Inventory Estimated Future Cost by Priority

High Medium Low Total High Medium Low Total

Field Validation (BH)

Alaska 0 1 158 159 $0 $11,400 $1,797,200 $1,808,600

Arizona 70 27 2,776 2,873 $109,300 $42,100 $4,333,500 $4,484,900

California 66 66 977 1,109 $343,000 $343,000 $5,078,100 $5,764,100

Colorado 16 41 957 1,014 $32,800 $84,000 $1,961,300 $2,078,100

Idaho 2 4 152 158 $30,800 $61,700 $2,343,000 $2,435,500

Montana/

South Dakota 18 32 727 777 $62,900 $111,800 $2,540,700 $2,715,400

Nevada 293 393 9,962 10,648 $308,000 $413,100 $10,471,400 $11,192,500

New Mexico/

Texas 107 9 1,378 1,494 $80,300 $6,800 $1,033,500 $1,120,600

Oregon/

Washington 6 1 288 295 $13,600 $2,300 $655,200 $671,100

Utah 13 69 2,800 2,882 $23,200 $123,400 $5,006,400 $5,153,000

Wyoming 3 4 688 695 $6,800 $9,100 $1,565,200 $1,581,100

Bureau-wide 594 647 20,863 22,104 $1,010,700 $1,208,700 $36,785,500 $39,004,900

Remediation of Physical Safety Hazards (HP)

Alaska 0 1 158 159 $0 $87,000 $13,739,200 $13,826,200

Arizona 70 27 2,776 2,873 $458,400 $176,800 $18,179,700 $18,814,900

California 66 66 977 1,109 $1,280,700 $1,280,700 $18,958,100 $21,519,500

Colorado 16 41 957 1,014 $162,300 $415,900 $9,707,600 $10,285,800

Idaho 2 4 152 158 $26,600 $53,300 $2,024,100 $2,104,000

Montana/

South Dakota 18 32 727 777 $280,100 $497,900 $11,312,100 $12,090,100

Nevada 293 393 9,962 10,648 $6,060,000 $8,128,300 $206,040,300 $220,228,600

New Mexico/ 

Texas 107 9 1,378 1,494 $1,860,800 $156,500 $23,964,800 $25,982,100

Oregon/

Washington 6 1 288 295 $104,300 $17,400 $5,008,700 $5,130,400

Utah 13 69 2,800 2,882 $93,200 $494,800 $20,078,800 $20,666,800

Wyoming 3 4 688 695 $52,200 $69,600 $11,965,300 $12,087,100

Bureau-wide 594 647 20,863 22,104 $10,378,600 $11,378,200 $340,978,700 $362,735,500

GRAND 

TOTAL 594 647 20,863 22,104 $11,389,300 $12,586,900 $377,764,200 $401,740,400

 
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 19

For the 22,104 sites in the working inventory, this feasibility study estimates that it will cost approximately $402.6

million to field-validate and remediate the known AML sites with physical safety hazards in AMSCM for all 

priorities. This total cost is divided by BH and HP activities as follows:

•	 $39.7 million to field-validate the AML sites (BH)

•	 $362.9 million to remediate physical safety hazards at these sites (HP)

Table 8. Estimated Future Cost To Field-Validate and Remediate 

AML Physical Safety Hazard Sites (by BLM State Office)

State

Working 

Inventory 

(Total AMSCM 

Physical Safety 

Hazard Sites)

Field Validation (BH) Remediation of Physical Safety 

Hazards (HP)

Total Estimated 

Future 

Average Cost 

per Site

Subtotal

Estimated 

Future 

Average Cost 

per Site

Subtotal

Alaska 159 $ 11,400 $ 1,812,600 $ 87,000 $13,833,000 $15,645,600

Arizona 2,873 1,600 4,596,800 6,500 18,674,500 23,271,300

California 1,109 5,200 5,766,800 19,400 21,514,600 27,281,400

Colorado 1,014 2,000 2,028,000 10,100 10,241,400 12,269,400

Idaho 158 15,400 2,433,200 13,300 2,101,400 4,534,600

Montana/

South Dakota 777 3,500 2,719,500 15,600 12,121,200 14,840,700

Nevada 10,648 1,100 11,712,800 20,700 220,413,600 232,126,400

New Mexico/

Texas 1,494 800 1,195,200 17,400 25,995,600 27,190,800

Oregon/

Washington 295 2,300 678,500 17,400 5,133,000 5,811,500

Utah 2,882 1,800 5,187,600 7,200 20,750,400 25,938,000

Wyoming 695 2,300 1,598,500 17,400 12,093,000 13,691,500

TOTAL 22,104 N/A $39,729,500 N/A $362,871,700 $402,601,200

BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 21

4. Conclusions

Since the AML Program’s inception the BLM has been committed to addressing high-risk and 

high-priority abandoned mine sites to protect public health and safety. This commitment endures 

and is demonstrated through continued on-the-ground success in addressing hazards associated with 

abandoned mines. It is strengthened by the BLM’s commitment to collaborate with federal, state, 

local, and tribal governments and nongovernmental partners to ensure that the highest-priority sites 

are addressed first. Continued program success can be achieved only through thoughtful strategic 

planning, targeted work, transparency, accountability, and innovation that occur through the 

exchange of ideas and ongoing dialogue with partners.

The BLM currently estimates the total cost of inventory and remediation activities at 22,104 AML 

sites to be $402.6 million. Of this, an estimated $11.4 million is needed to address all high-priority 

sites, and an estimated $12.6 million is needed to address medium-priority sites impacting public 

safety. The BLM currently estimates that $377.7 million is needed to address those sites characterized 

as low priority. Injuries and accidents do still occur at these sites. Because changing circumstances 

may warrant changes in priority status, the BLM will closely track and monitor low-priority sites 

and shift priorities as needed. With the methodology of this feasibility study now in place, the BLM 

anticipates updating this study in conjunction with future strategic planning activities. AML Program 

managers will be able to measure progress, report results, and refine future costs and timeframes to 

complete remaining remediation for low-priority physical safety AML sites. 

As the number of completed sites increases, additional dollars will be absorbed into monitoring and 

maintenance activities. Monitoring and maintenance efforts are necessary to avoid problems of adits 

and shaft closures failing over time; fences and signs being vandalized or otherwise damaged; and 

remedial activities adversely impacting wildlife. The BLM coordinates and integrates monitoring and 

maintenance efforts with other BLM resource and safety programs to ensure that corrective actions 

remain compliant with safety and environmental standards and that any lessons learned benefit 

subsequent risk-reducing efforts.

In addition, the BLM continues to emphasize the following activities to ensure that the highest 

priority sites are addressed in a timely and cost-effective manner. 

•	 Strategic Planning. The best and most effective work is accomplished through thoughtful and 

careful planning. Accordingly, the BLM is currently revising its strategic plan for the AML 

Program. The BLM Strategic Plan will provide details on anticipated workload targets to meet 

program goals.
22 BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures

•	 AMSCM: The need for current, complete, and 

accurate data in AMSCM is critical to measuring 

progress and reporting results for AML Program 

activities. The BLM is improving the AMSCM 

training, several state offices and field offices have 

robust inventory efforts underway, and available 

technologies are being considered for use by on-theground field personnel and contractors to capture 

and upload data to AMSCM. 

•	 Best Practices. Review of activity-based costing shows 

areas for improvement in how field validation activities 

and site remediation activities are conducted throughout 

the BLM. The BLM is following up to identify the most 

efficient and effective practices in the field and will assist 

state offices in adopting such practices.

•	 Partnerships. The BLM continues to pursue 

additional partnerships with federal land 

management agencies, such as the U.S. Forest Service 

and the National Park Service, to find ways to share 

resources and to collaborate with state AML agencies. 

There may be ways, for example, to use joint or

multi-agency teams to conduct field validation 

activities in locations with mixed land ownership or

adjacent sites. 
BLM Abandoned Mine Lands Program Feasibility Study for AML Inventory Validation and Physical Safety Closures 23

Appendix A, 

Proximity Analysis Data Source Definitions

USGS Geographic Names Information System (GNIS): The GNIS is the federal standard for 

geographic nomenclature. The U.S. Geological Survey developed the GNIS to maintain uniform 

feature name usage throughout the government and to promulgate standard names to the public. It 

is the official repository of domestic names and includes parks, populated places, schools, and other 

features of note. 

USGS GNIS Definitions of Note:

•	 Populated Place: Defined as “representing a named community with a permanent human 

population, usually not incorporated and with no legal boundaries, ranging from rural clustered 

buildings to large cities and every size in between; includes metropolitan areas, housing 

subdivisions, developments, modular home communities, and named neighborhoods (village, 

town, settlement, hamlet, trailer park, etc.). The boundaries of most communities classified as 

Populated Place are subjective and cannot be determined.”

•	 Historical: Some features are listed in GNIS as “historical,” defined as “specifically and only that 

the feature no longer exists on the landscape,” with no reference to age, size, condition, extent

of habitation, type of use, or any other factor. For example, a ghost town is not “historical,” only

abandoned, as might be noted in the historical notes field. Most “historical” features are (or were) 

manmade, but they can also be natural features, such as shoals that are washed away by a storm or 

a hill leveled by mining activity.

•	 Any feature with the “historical” designation was shifted from a high to medium priority,

considering that the feature was no longer present in the landscape but could still potentially 

attract visitors.

BLM Facility Asset Management System (FAMS): Tracks BLM-owned facilities, including 

recreation, campgrounds, administrative sites, buildings, and others.10

FEMA HAZUS MH (Multihazard Loss Information Software): The HAZUS dataset contains

information on the Public Elementary/Secondary School Universe Survey Data from 2005–06, 

and the Private School Universe Survey Data from 2004-05, as maintained by National Center for 

Education Statistics, U.S. Department of Education.11 

10Downloaded from ArcIMS map services Site Mapper, June 2010.

11HAZUS MH MR4 (v1.4) (FEMA) data disks, published August 2009.

The mention of company names, trade names, or commercial products does not constitute endorsement or recommendation for use by the 

federal government.