Analysis Of Negligible Disturbance Definition

Analysis Of Negligible Disturbance Definition

The law says casual collecting results “in only negligible disturbance to the Earth’s surface and other resources” and the term negligible disturbance “shall be determined by the Secretary.” The proposed rule imposes a one yard square limitation on ground disturbance citing a long standing practice of BLM which is arbitrary and has no foundation in regulation and is in fact contrary to existing regulations nor is it practical in the field where rocks don’t always come in one yard square blocks.

Language regarding “negligible disturbance” is found in Supplementary Information and in the proposed rule.

The pertinent portions of the Supplementary Information section state:

(page 88183 left column 2nd paragraph)

“Proposed § 49.810(a)(3) would clarify that ‘‘negligible disturbance’’ for casual collecting means little or no change to the surface of the land, and minimal or no effect to natural and cultural resources. This proposed definition would specify that in no circumstance may the surface disturbance exceed 1 square yard (3 feet by 3 feet) per individual collector; that in cases of multiple collectors each square yard of surface disturbance must be separated by at least 10 feet; and that all areas of surface disturbance must be backfilled with the material that was removed in order to render the disturbance substantially unnoticeable to the casual observer. The reason for using the ‘‘1 square yard’’ maximum is that this would be similar to longstanding BLM practice, and such consistency is encouraged by PRPA. In the context of compliance with the National Environmental Policy Act (NEPA) in the issuance of research permits for BLM, for instance, a proposal to engage in surface disturbance of anything larger than 1 square meter is not usually subject to categorical exclusion but is subject to further analysis under NEPA. The fossil-collecting community should, therefore, already be familiar with this type of threshold. For purposes of managing ‘‘negligible disturbance,’’ 1 square yard is considered to be approximately equal to 1 square meter.

The proposed definition would also specify that collecting areas need to be separated by at least 10 feet where there is surface disturbance. The separation would reduce cumulative effects to other resources. Where there is no surface disturbance, there is no need to separate collecting areas.”

The proposed rule 49.810(a) states:

(page 88195 right column last paragraph)

“(a) What is casual collecting? (a) Casual collecting means the collecting without a permit of a reasonable amount of common invertebrate or plant paleontological resources for non-commercial personal use, either by surface collection or the use of non-powered hand tools, resulting in only negligible disturbance to the Earth’s surface or paleontological or other resources.”

The proposed rule 49.810(a)(3) states:

(page 881956 left column starting with third paragraph)

“(3) Negligible disturbance means little or no change to the surface of the land and minimal or no effect to natural and cultural resources, specifically: (i) In no circumstance may the surface disturbance exceed 1 square yard (3 feet × 3 feet) per individual collector; (ii) For multiple collectors, each square yard of surface disturbance must be separated by at least 10 feet; (iii) All areas of surface disturbance must be backfilled with the material that was removed so as to render the disturbance substantially unnoticeable to the casual observer.”

The proposed rule 49.810(b) states:

(page 881956 left column last paragraph)

“(b) In order to preserve paleontological or other resources, or for other management reasons, the authorized officer may establish limitations on casual collecting, including but not limited to reducing the weight of common invertebrate or plant paleontological resources below the amount specified in this subpart; limiting the depth of disturbance; establishing site-specific dates or locations for collecting; or establishing what is common in a specific area.”


1. Use of the word “Negligible”. ​In the proposed rule, part of the negligible definition says that it “means little or no change to the surface of the land, and minimal or no effect to natural ​ and cultural resources” [emphasis added]. Saying that negligible means no change or ​ no effect is categorically wrong. By definition negligible means there is change or impact. PRPA says casual collecting is allowed with the caveat there is negligible disturbance, meaning the law anticipates some disturbance as a result of casual collecting. Therefore the use of the word “no” is not in accordance with the law and is incorrect when defining the word negligible.

2. The use of non-powered hand tools by definition limits disturbances to “negligible”. ​PRPA says “The term `casual collecting’ means the collecting of a reasonable amount of common invertebrate and plant paleontological resources for non-commercial personal use, either by surface collection or the use of non-powered hand tools resulting in only negligible disturbance to the Earth’s surface and other resources. As used in this paragraph, the terms `reasonable amount’, `common invertebrate and plant paleontological resources’ and `negligible disturbance’ shall be determined by the Secretary.” [emphasis added].

The law states that using “non-powered hand tools” is specifically allowed resulting in only “negligible disturbance”. Therefore, it should be acknowledged in the proposed rule that the law relates the use of “non-powered hand tools” with “negligible disturbance”. Because of the relationship between “non-powered hand tools” and “negligible disturbance” as stated in the law, it is understood that by using “non-powered hand tools” the result will be “negligible disturbance”. The use of “non-powered hand tools” while casually collecting paleontological resources naturally limits the disturbed area (size and depth) of individual collecting events and the total cumulative effect over time. Field experience shows backfilling naturally occurs over time without the need to immediately fill an excavation. Immediate backfilling impedes the ability of the casual collector to engage in normal collecting activities which are allowed by law. As a result, further defining “negligible disturbance” to include size of disturbance, distance between disturbances and requirements to backfill the disturbed areas are not necessary. The resulting regulation will be more simple and easier to understand than the proposed regulation for the public and law enforcement, complying with EO12866(12) “Each agency shall draft its regulations to be simple and easy to understand, with the goal of minimizing the potential for uncertainty and litigation arising from such uncertainty.

Furthermore this reduces the burden on individuals and law enforcement to carefully measure distances between disturbances, monitor disturbance size, backfilling a collecting site (for enforcement determining intent to backfill) such that it is substantially unnoticeable to a casual observer. In accordance with EO 12866 (11) “Each agency shall tailor its regulations to impose the least burden on society, including individuals, … consistent with obtaining the regulatory objectives…

3. The rule states that “​in no circumstance may the surface disturbance exceed 1 square yard

​ (3 feet by 3 feet) per individual collector”. According to the supplementary information “The reason for using the ‘‘1 square yard’’ maximum is that this would be similar to longstanding BLM practice, and such consistency is encouraged by PRPA. In the context of compliance with the National Environmental Policy Act (NEPA) in the issuance of research permits for BLM, for instance, a proposal to engage in surface disturbance of anything larger than 1 square meter is not usually subject to categorical exclusion but is subject to further analysis under NEPA. The fossil-collecting community should, therefore, already be familiar with this type of threshold. For purposes of managing ‘‘negligible disturbance,’’ 1 square yard is considered to be approximately equal to 1 square meter.” The use of one square yard may be relevant to archaeological excavations (where a person might be working in unconsolidated soils or other materials), areas where fossils have weathered out of rock, or remain in an unconsolidated host material due to lack of natural processes that would otherwise turn sediments into consolidated rocks.

However, the restriction of one square yard is not a practical or reasonable way to manage disturbances caused by casual collection of fossil bearing rocks on Federal lands. A major issue is that consolidated rocks, such as fossil-bearing shales and bedded limestones, where invertebrate and plant fossils are commonly found, do not occur naturally jointed in square yards.

As a specific example, the vast majority of fossil trilobites and associated faunas that are collected from the Cambrian exposures of the House Range in western Utah on BLM managed lands are collected by splitting rocks that are naturally jointed into blocks of various shapes and sizes most of which are larger than one square yard. The size of these blocks of rock is determined by the material composition of the rock, tectonic processes creating the Basin and Range and weathering process as they are exposed near the surface of the earth. These factors began over 500 million years ago. The bureau, by regulating the size of disturbance to one square yard, ignores the fact neither the bureau or the casual collector has control over the natural processes that dictate the size and shape of fossil bearing rocks. Therefore, by using one square yard to define and regulate what is “negligible disturbance” the bureaus may restrict the collecting of fossils occurring in rocks that do not meet this restrictive standard.

According to EO12866 Section 1(b)(7) “Each agency shall base its decisions on the best reasonably obtainable scientific, technical, economic and other information concerning the need for, and consequences of, the intended regulation or guidance document.” It does not appear that the bureau took into consideration the “reasonably obtainable scientific” or “technical” information of well understood principles of fossil occurrence, rock formation, tectonic movements and weathering when developing this regulation. By failing to understand the practical consequences of the one-square-yard limit in the proposed regulation the bureaus inadvertently violated the mandate in PRPA that “the Secretary shall allow casual collecting.

The bureau, in justifying the restriction of disturbances to one square yard, statesthat the proposed regulation should “be similar to longstanding BLM practice” of limiting disturbance to one square yard and that casual collectors should be “familiar with this type of threshold”. This example used by the bureau is based on the issuance of research permits. Vertebrate paleontologists who have obtained BLM survey permits may be familiar with this restriction of one square meter. Invertebrate paleontologists and paleobotanists have not been required to have a permit until PRPA and thus are far less likely to be familiar with this practice. The casual collector would in fact not be familiar with this type of regulation or requirement since it has only been a BLM practice used for permits issued to academic vertebrate paleontologists since the early 1990s. Nor is there evidence this limitation based on scientific or technical information as required by EO12866.

In development of the draft Environmental Assessment (EA) to address the terms “negligible disturbance” and “reasonable amount” the bureaus acknowledged that under existing mining regulations that disturbances of up to 5 acres only require the BLM to be notified of the operation, no approval is necessary. The EA says “Because PRPA requires the bureaus to allow casual collection and to define negligible disturbance, BLM inferred that the area must be greater than zero. Conversely, 5 acres is the area of public lands managed by BLM that may be disturbed by exploration conducted in the context of mining operations, for which only Notice to the BLM is required, but not approval of a mining Plan of Operations, under BLM’s surface management regulations at 43 CFR Part 3809. See 43 CFR 3809.21. Casual collecting of paleontological resources by the public requires neither a permit, nor notice to the BLM; therefore, in order the disturbance associated with casual collecting to be considered “negligible,” the BLM determined that the area must be less than 5 acres.” Based on the bureaus’ own determination disturbances up to 5 acres do not require a permit and as such are considered “negligible”. Furthermore, the bureaus’ claim that “a proposal to engage in surface disturbance of anything larger than 1 square meter is not usually subject to categorical exclusion but is subject to further analysis under NEPA” is not based in law or regulation. In fact, there are categorical exclusions (CX) that allow surface disturbances of up to 5 acres without further analysis under NEPA (see BLM NEPA Handbook H-1790-1 and 516 DM 11). For solid minerals the CX says “Disposal of mineral materials, such as sand, stone, gravel, pumice, pumicite, cinders, and clay, in amounts not exceeding 50,000 cubic yards or disturbing more than 5 acres, except in riparian areas.” as well as multiple references relating to the harvesting of trees where up to “0.5 mile of temporary road construction” is allowed without a NEPA analysis. EO12866 Section 1(b)(10) says “Each agency shall avoid regulations that are inconsistent, incompatible, or duplicative with its other regulations or those of other Federal agencies.”  It would be appropriate for the bureaus, instead of restricting “casual collecting” to one square yard, to be consistent with existing policies that allow for disturbed areas up to 5 acres. There are 24,200 square yards in 5 acres. To restrict disturbance to 0.0002 acres is so overly restrictive that it is neither reasonable nor rational.

In the draft EA the bureaus further justified the one square yard limit by stating that they are “concerned that the cumulative effects to the environment and to the resource may be too large… The cumulative effects are especially large when a group of people collect in a similar area, or return to an area over several years.” In order to assess the validity of this concern, an analysis of BLM managed Federal lands in Millard County UT was performed. Millard county is the home of one of the most popular areas for casual collection of fossils on BLM managed Federal lands (see

Approximately 66% of all of the lands in Millard county are managed by the BLM. This represents approximately 2.9 million acres of land. To limit this area further, the known concentration of fossil collecting areas is restricted to approximately 500,000 acres in the vicinity of the House Range, Drum Mountains and Confusion Range. In order to determine the total disturbance in this area an assessment of specific sites that are utilized for the collection of trilobite and other fossils was completed. This evaluation of data showed that the cumulative disturbance from dozens of individual fossil collecting sites is approximately 5 acres, the largest single disturbance being 0.64 acres. To put this in perspective, the total disturbed area represents 0.0002% of all of the BLM managed lands in Millard County, and only 0.001% of the lands in the fossil bearing areas identified above.

In the context of the precedence under existing BLM regulations that “negligible disturbance” can be a single disturbance up to 5 acres, it is clear that even in this area of high use for the collection of fossils the total disturbance is negligible. Specific to the bureau concerns about cumulative effect of collecting over time. It is important to note that according to the American Museum of Natural History that fossil collecting by amateurs and hobby collectors goes back to the 1930’s or over 80 years. (see

There is documented evidence that Lloyd Gunther, a famed amateur fossil collector, referenced in both of the web links above, started collecting in this area as early as 1931. In this case it is clear that the bureaus do not understand, or made no effort to quantify, the truly negligible disturbance that has accumulated over this time and their concerns about cumulative effect of casual fossil collecting which has gone on for more than 80 years is unfounded.

Collecting fossils in situ with hand tools is primarily done for trilobites, leaves and insects. This is due to the trilobite’s thin exoskeleton which does not remain intact when weathering to the surface. The rare exception is trilobite exoskeletons, most notably Elrathia kingi, which are thickened with cone-in-cone calcite and thus are durable and survive weathering to the surface. Plants and insects are most commonly preserved as carbon films and thus do not survive weathering to the surface.

Rock exposures on BLM lands with these kinds of fossils are a small fraction of fossil-bearing rocks, let alone the overall acreage of non-fossil bearing sedimentary, igneous, and metamorphic rocks further limited by blankets of topsoil and alluvium which cover all types of rock. Therefore the cumulative effect of disturbance is restricted to localized areas thus making relatively easy for bureau staff to monitor the areas of disturbance for those reaching the allowed 5 acre limit.

It should also be acknowledged that in this same area of the House Range the BLM has permitted the use of these same Class 5 fossil bearing rocks for a variety of salable mineral resources, including flagstone and crushed decorative rock. These permitted leases total approximately 23 acres. This shows that the bureau has little concern for the supposed scarcity of paleontological resources. One of these is a rock crushing operation that has recently operated in a popular fossil collecting site that many call “Red Wash”. The primary fossil bearing layers have been removed by heavy equipment and crushed into decorative ground covering. Based on experience collecting at this site and the amount of rock removed by this operation, it would be reasonable to assume that hundreds of thousands of trilobites and other arthropods have been destroyed.

4. The rule requires a ten foot separation between disturbances. T​he Supplemental Information and proposed rule say ​“For multiple collectors, each square yard​ of surface disturbance must be separated by at least 10 feet”. There is no basis explained in the supplemental information nor is there a precedent for this requirement in other rules regarding ground disturbance.

This requirement is not listed in the draft EA for PRPA. The proposed rule does not explain the scientific or technical basis for this separation as required by EO12866 (7). Furthermore it is not consistent with other bureau rules that address land disturbance limitations EO12866(10) requiring consistency between regulations. In 43 CFR 3809.21, exploration mining activities can disturb up to 5 acres using heavy equipment with only prior notice to the BLM.

Since disturbances up to 5 acres are allowed by other regulations, the proposed rule should not be concerned about the proximity of small adjacent disturbances unless a contiguous disturbance exceeds the 5 acre limit. Since the total of all combined areas of disturbance made by casual collectors in the House Range, Utah, among the most heavily collected fossil areas on BLM managed lands, has not exceeded 5 acres over the past 80 years, it seems there is no cause for such restrictive regulations on the casual collector who is already limited to the use of non-powered hand tools. Where disturbances are juxtaposed they lend themselves to the natural process of back filling as adjacent areas are collected, reclaiming the disturbance over time. The Supplemental information also says “The separation would reduce cumulative effects to other resources.” This is an unsubstantiated statement. In fact, if the ten foot separation rule goes into effect it will likely cause more widespread surface disturbance than would have occurred if adjacent collecting is allowed. Most casual collectors see a disturbance and collect adjacent to it, backfilling the original disturbance. With a ten-foot separation rule, casual collectors will be forced to move laterally ten feet creating a new disturbance, the next person another ten feet etc.

Disturbance will spread laterally over a much greater area, causing more disturbance than what would have occurred otherwise thus increasing, rather than reducing, the potential to affect other resources. The requirement to separate disturbances by 10 feet should be removed from the proposed regulation.

5. Casual collectors must backfill all disturbed areas. ​The proposed rule says “All areas of surface disturbance must be backfilled with the material that was removed so as to render the disturbance substantially unnoticeable to the casual observer.” The requirement to backfill shows a lack of understanding regarding the collection of many fossils that are found in situ.

Using the previously mentioned fossil bearing areas in the vicinity of the House Range in Utah, it is critical to note that the vast majority of the fossil bearing layers are found on mountain or hillsides. In these cases it is virtually impossible with the use of “non-powered hand tools” to backfill collecting areas with the materials that are previously removed. Neither the rule nor the supplemental Information explains the basis for the requirement or a satisfactory procedure on how to properly backfill materials in this situation.

Additionally, in almost all cases backfilling will disturb more than an additional one square yard of area. It is not practical to expect that a person will be able to adequately return disturbed materials back into the original area without causing additional disturbance. Rocks that have been removed and subsequently split will not fit back into the disturbance due to the inability to reconstitute rocks into the same form. It is also unclear what the view of a casual observer would be. Who is this “casual observer”? A bureau employee would not qualify in this role. Instead this person would be someone without knowledge of common practices used the collection of fossils and as such would not be familiar with disturbed areas. The bureaus use an arbitrary and unmeasurable way to regulate and enforce this requirement.

Each of these examples shows that the proposed rule fails to comply with EO12866 (7)(11)(12). In review of other law and bureau regulations, there are no requirements requiring backfilling disturbances caused by casual use. It is important to recognize that by definition “negligible disturbance” is insignificant and therefore does not require mitigation. The requirement for backfilling should be removed from the proposed rule.

6. Why is casual collecting limited to 1 square meter of surface disturbance?​ In the Supplemental Information of the proposed rule it says ”The reason for using the ‘‘1 square yard’’ maximum is that this would be similar to longstanding BLM practice, and such consistency is encouraged by PRPA. There is no evidence that this practice of using a 1-square-yard maximum is based in scientific or technical information for paleontological investigations as required by EO12866 (7). There has not been a long standing practice of limiting casual collecting to 1 square yard, because until PRPA and this new rule there were no law requiring regulation. A one square meter limitation on paleontology research survey permits has been used for many years however the restriction on research permits is not commonly known by casual collectors nor applied to their activities. The bureaus need to provide evidence how the one square meter of disturbance for survey research permits was determined and what science and technical information was used at the time it was established.

The proposed rule says ”The reason for using the ‘‘1 square yard’’ maximum is that this would be  similar to longstanding BLM practice, and such consistency is encouraged by PRPA” [emphasis added]. This statement is false. PRPA says “…where such collection is consistent with the laws governing the management of those Federal land and this subtitle” [emphasis added]. PRPA clearly​ ​ states that consistency with existing laws must be followed, NOT practices as used in the justification for implementing such limitations as described in the Supplemental Information.

7. The draft Environmental Assessment (EA) under the National Environmental Policy Act (NEPA) for PRPA regulations addresses casual collecting. ​It says “Casual collecting activities are not anticipated to cause adverse impact to paleontological or other natural or cultural resources. However, if the BLM is aware that a paleontological resource may be depleted, the bureau may take action to prevent further depletion of the resource, either by closing the area to casual collection, or by limiting or restricting the definition of reasonable amount or negligible disturbance for that area.“  NEPA is used to evaluate impacts to the human environment.

NEPA is not used to evaluate whether there is enough oil, gas, gold, silver, fossils, gravel, or other resources remaining in the ground, but rather to evaluate how the actions of getting those resources affects the environment. The EA is not out for public comment and should never be finalized since casual collecting is within the the bounds of a categorical exclusion. If the bureaus choose to pursue an EA, they need to be certain the EA focuses on the how extracting a resource impacts to the environment, not on the the resource itself. The draft EA is found at <>.


Supplementary Information section should read:

“Proposed § 49.810(a)(3) would clarify that ‘‘negligible disturbance’’ for casual collecting means little change to the surface of the land, and minimal effect to natural and cultural resources. Recognizing the relationship as stated in the law between “non-powered hand tools” and negligible disturbance” is understood that by using non-powered hand tools the result will be negligible disturbance. Cumulative effect must also be considered. To ensure consistency between laws and regulations, this proposed definition would specify cumulative negligible disturbance as no single contiguous site shall exceed 5 acres of disturbance. The bureau considered limiting disturbance to one square yard for consistency with vertebrate paleontology permitting practice. Upon further investigation the bureau found the one-square-yard limit is not required by law or regulation and is far more limiting than ground disturbance allowed under categorical exclusions of the National Environmental Policy Act (NEPA) (refer to BLM NEPA Handbook H-1790-1 and 516 DM 11) currently in use by the bureaus, thus the one-square-yard limit was abandoned. After investigating areas known to be casual collected, it was found there are a limited number of sites repeatedly visited by casual collectors. In those areas the bureau found no single site disturbed in excess of one acre after more than 80 years of repeated casual collecting. The bureaus further found that the disturbed areas heal themselves as continued collecting backfills previously disturbed areas and naturally revegetate. The bureaus attributed the slow growth and low level of disturbance to the requirement for casual collectors to use only non-powered hand tools, thus the bureaus feel this natural limitation is an adequate control on disturbance without further regulatory oversight. Since heavily collected areas are limited in number and the disturbance expands very slowly, it will not be a burden on bureau staff to monitor the size of disturbed sites. If, in the future, a disturbed site approaches 5 acres the bureau will evaluate potential impacts in context of compliancewith NEPA.

Suggested wording of proposed rule 49.810(a)(3):

“Negligible disturbance means surface collecting or using non-powered hand tools which naturally results in only negligible disturbance ensuring little change to the surface of the land and minimal effect to natural and cultural resources. Cumulative disturbance shall not exceed 5 contiguous acres without further analysis under NEPA. ”


It is anticipated that the discussion above will stimulate other ideas related to the proposed rule on “negligible disturbance”. Please share your thoughts to encourage dialog. Remember not to cut and paste these comments (form letters will be combined and counted as a single comment) but rather use the points from the discussion above to develop your comments on the proposed rule adding data you find and your personal experiences. Above all else take the time to write and send your comments and encourage all you know to do likewise. Your voice counts!

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