highly erodible soil map units as "potentially highly erodible." The final determination of erodibility for an individual field containing these soil map unit delineations will be made by an on-site investigation.

§ 12.22 Highly erodible field determination criteria.

(a) Highly erodible land shall be considered to be predominant on a field if either:

(1) 33.33 percent or more of the total field acreage is identified as soil map units which are highly erodible; or

(2) 50 or more acres in such field are identified as soil map units which are highly erodible.

(b) A person may request the modification of field boundaries for the purpose of excluding highly erodible land from a field. Such a request must be submitted to, and is subject to the approval of, ASCS.

(c) Small areas of noncropland within or adjacent to the boundaries of existing highly erodible crop fields such as abandoned farmsteads, areas around filled or capped wells, rock piles, trees or brush which are converted to cropland are considered to meet the requirement of § 12.5(c) if they are included in an approved conservation plan for the entire highly erodible field.

§ 12.23 Conservation plans and conservation systems.

(a) A conservation plan or a conservation system developed for the purposes of § 12.5(b) must be based on and in conformity with the SCS field office technical guide. For highly erodible croplands which were in production prior to December 23, 1985, the applicable conservation systems in the field office technical guide are designed to achieve substantial reductions in soil erosion, taking into consideration economic and technical feasibility and other resource related factors. For highly erodible lands that are converted from native vegetation, i.e., rangeland or woodland, to crop production after December 23, 1985, the applicable conservation systems in the field office technical guide are designed to control soil losses to a level that will attain or approximate the

soil loss tolerance level. Any conservation plans or systems that were approved prior to February 11, 1988, are deemed to be in compliance with this paragraph.

(b) Persons who require SCS assistance for the development of a conservation plan or the installation of a conservation system are encouraged to request this assistance well in advance of deadline dates for compliance; otherwise the person may not be able to comply with these provisions and maintain eligibility for USDA program benefits.

(c) Conservation districts approve or disapprove conservation plans or conservation systems after SCS determines that the plans or systems conform to the SCS field office technical guide. If a conservation district fails, without due cause, to act on a request for conservation plan or conservation system approval within 45 days, or if no conservation district exists, SCS will approve or disapprove, as appropriate, the conservation plan or system in question.

(d) A person is considered to be actively applying a conservation plan for purposes of § 12.5(b) if the plan is being applied according to the schedule specified in the plan and the applied practices are properly operated and maintained. It is the responsibility of the person to:

(1) Annually certify that the conservation plan is being actively applied after January 1, 1990 and

(2) Arrange for a revision of the conservation plan with SCS, if changes are made in land use, crop rotation or management, conservation practices, or in the original schedule of practice installation.

(e) Persons who are adversely affected by the determinations made under this subpart and believe that the requirements of this subpart were improperly applied may appeal the decision to SCS under § 12.12.

[52 FR 35200, Sept. 17, 1987, as amended at 53 FR 3999, Feb. 11, 1988]

Subpart C-Wetland Conservation

§ 12.30 SCS responsibilities regarding wetlands.

In carrying out the provisions of this part, SCS shall:

(a) Make available to the public an approved county list of hydric soil map units, which is based upon the National List of Hydric Soils;

(b) Maintain a list of hydrophytic vegetation derived from the National List of Plant Species That Occur in Wetlands;

(c) Consult with the Fish and Wildlife Service on determinations of exemptions made under § 12.5(d)(1) and (d)(2) and on matters relating to the identification of wetland,

(d) Oversee the development and application of criteria to identify hydric soils in consultation with the National Technical Committee for Hydric Soils, and

(e) Consult with the Fish and Wildlife Service and others in developing the National List of Plant Species that Occur in Wetlands and in providing guidance in applying the lists of hydric soils and plant species to matters concerning wetland and converted wetland.

§ 12.31

Wetland identification criteria. (a) Hydric soils. (1) SCS shall identify hydric soils through the use of published soil maps which reflect soil surveys completed by SCS. If a published soil map is unavailable for a given area, SCS may use unpublished soil maps which were made according to the specifications of the National Cooperative Soil Survey or may conduct an on-site evaluation of the land.

(2) SCS shall determine whether an area of a field or other parcel of land has a predominance of hydric soils that are inundated or saturated as follows:

(i) If a soil map unit has hydric soil as all or part of its name, that soil map unit or portion of the map unit related to the hydric soil shall be determined to have a predominance of hydric soils;

(ii) If a soil map unit is named for a miscellaneous area that meets the criteria for hydric soils (i.e., riverwash, playas, beaches, or water) the soil map

unit shall be determined to have a predominance of hydric soils; or

(iii) If a soil map unit contains inclusions of hydric soils, that portion of the soil map unit identified as hydric soil shall be determined to have a predominance of hydric soils.

(3) List of hydric soils. (i) Hydric soils are those soils which meet criteria set forth in the publication "Hydric Soils of the United States 1985” which was developed by the National Technical Committee for Hydric Soils and which is incorporated by reference. This publication may be obtained upon request by writing the Soil Conservation Service, U.S. Department of Agriculture, P.O. Box 2890, Washington, DC 20013, and is available for inspection at the Office of the Federal Register Information Center, Room 3801, 1100 L Street NW., Washington, DC 20408. Incorporation of this publication by reference was approved by the Director of the Federal Register on June 24, 1986. The materials are incorporated as they exist on the date of the approval and a notice of any change in these materials will be published in the FEDERAL REGISTER.

(ii) An official list of hydric soil map units shall be maintained at the local SCS office and shall include

(A) All soils from the National List of Hydric Soils that can be found in that field office area, and

(B) Any soil map units or areas which the State conservationist determines to meet such hydric soil criteria.

(iii) Any deletions of a hydric soil unit from the hydric soil map unit list must be made according to the established procedure contained in the publication "Hydric Soils of the United States, 1985" for adding or deleting soils from the National List of Hydric Soils.

(b) Hydrophytic vegetation. Hydrophytic vegetation consists of plants growing in water or in a substrate that is at least periodically deficient in oxygen during a growing season as a result of excessive water content.

(1) A plant shall be considered to be a plant species that occurs in wetland if such plant is listed in the National List of Plant Species that Occur in Wetlands. The publication may be ob

tained upon request from the U.S. Fish & Wildlife Service, National Wetland Inventory, Monroe Bldg. Suite 101, 9720 Executive Center Drive, Saint Petersburg, Florida 33702.

(2) For the purposes of the definition of "wetland" in § 12.2(a)(28) of this part, land shall be determined to have a prevalence of hydrophytic vegetation if:

(i) SCS determines through the use of the formula specified in paragraph (b)(3) of this section that under normal circumstances such land supports a prevalence of hydrophytic vegetation. The term "normal circumstances" refers to the soil and hydrologic conditions that are normally present, without regard to whether the vegetation has been removed; or

(ii) In the event the vegetation on such land has been altered or removed, SCS will determine if a prevalence of hydrophytic vegetation typically exists in the local area on the same hydric soil under the same hydrological conditions.

(3) The determination of prevalence of hydrophytic vegetation will be made in accordance with the following provisions:

(i) Plant classification. The National List of Plant Species that Occur in Wetlands classifies vascular plant species found in the United States and Puerto Rico into five indicator groups based upon their expected occurrence in wetlands. Obligate species are expected to occur in wetlands more than 99 percent of the time; facultative wet

PI =

(B) A mean prevalence index (PI) value of less than 3.0 shall indicate that the area exhibits a prevalence of hydrophytic vegetation.

(c) Artificial wetland. (1) An area shall be considered to be an artificial wetland for the purposes of § 12.5(d)(1) (ii) and (iii) of this part if such area was formerly nonwetland or wetland on which conversion was started or completed before December

23, 1985, but now meets wetland criteria due to the action of man.

(2) Notwithstanding the provisions of paragraph (c)(1) of this section, wetlands which are created in order to mitigate the loss of other wetlands as a result of irrigation, recreation, municipal water, flood control or other similar projects shall not be considered to be artificial wetland for the

purposes of § 12.5(d)(1) (ii) and (iii) of this part.

(d) For the purposes

of

§ 12.5(a)(1)(v) of this part, SCS, in consultation with the Fish and Wildlife Service, U.S. Department of the Interior, shall determine whether the effect of any action of a person associated with the production of an agricultural commodity on converted wetland has a minimal effect on the hydrological and biological aspect of wetlands. Such determination shall be based upon an environmental evaluation analyzing the effect of the action on the maintenance of wetland values of the particular wetland under consideration and other related wetlands, and will be made through an on-site evaluation. A request for such determination will be made prior to the beginning of activities that would convert the wetland. If a person has converted a wetland and then seeks a determination that the effect of such conversion on wetland was minimal, the burden will be upon the person to demonstrate to the satisfaction of SCS that the effect was minimal. The production of an agricultural commodity on any portion of a converted wetland in conformance with a minimal effect determination by SCS is exempt under § 12.5(d) of this part. However, any additional action of a person that will change the hydrological or biological characteristics of a wetland for which a minimal effect determination has been made shall be reported to SCS for a determination of whether the effect continues to be minimal. The loss of a minimal effect determination will cause a person who produces an agricultural commodity on the converted wetland after such change in status to be ineligible, under § 12.4, for program benefits.

[52 FR 35200, Sept. 17, 1987, as amended at 53 FR 3999, Feb. 11, 1988]

§ 12.32 Converted wetland identification criteria.

(a) Converted wetland shall be identified by determining whether the wetland was altered so as to meet the definition of converted wetland set forth in § 12.2(a)(6). In making this determination, the following factors are to be considered:

(1) Where hydric soils have been used for production of an agricultural commodity and the drainage or other altering activity is not clearly discernable, SCS will compare the site with other sites containing the same hydric soils in a natural condition to determine if the hydric soils can or cannot be used to produce an agricultural commodity under natural conditions. If the soil on the comparison site could not produce an agricultural commodity under natural conditions, the subject wetland will be considered to be converted wetland.

(2) Where woody hydrophytic vegetation has been removed from hydric soils which permits the production of an agricultural commodity, and wetland conditions have not returned as the result of abandonment under § 12.33(b), the area will be considered to be converted wetland.

(3) A pothole or a playa shall not be determined to be converted wetland despite manipulations that occurred prior to December 23, 1985, if that area continues to meet wetland criteria. Any other wetland area that is seasonally flooded or ponded (surface water is present for extended periods especially early in the growing season even though it may be absent by the end of the season in most years) which has been manipulated prior to December 23, 1985 but otherwise continues to meet wetland criteria, shall not be determined to be converted wetland.

(b) A wetland shall not be considered to be converted if:

(1) Production of an agricultural commodity on such land is possible as a result of a natural condition, such as drought, and

(2) It is determined that the actions of the person producing such agricultural commodity does not permanently alter or destroy natural wetland characteristics. Destruction of herbacaeous hydrophytic vegetation, (i.e., plants other than woody shrubs or trees) as a result of the production of an agricultural commodity shall not be considered as altering or destroying natural wetland characteristic if such vegetation could and has been allowed to return following cessation of the natural condition which made produc

tion of the agricultural commodity possible.

§ 12.33 Use of wetland and converted wetland.

(a) The provisions of § 12.32(a)(3) are intended to protect remaining functional values of the wetlands described therein. Persons may continue to farm such wetlands under natural conditions or as they did prior to December 23, 1985. However, no action can be taken to increase effects on the water regime beyond that which existed on such lands on or before December 23, 1985 unless SCS determines the effect on remaining wetland values would under

be

§ 12.5(d)(1)(v).

minimal

(b) Unless otherwise provided in this part, the production of an agricultural commodity on wetlands that were converted before, or for which the conversion was commenced before, December 23, 1985, is exempted by law from these regulations for the area which was converted or the minimum area the commenced activity could convert. Maintenance or improvement of these converted wetlands for the production of agricultural commodities are not subject to this rule so long as such actions do not bring additional wetland into the production of an agricultural commodity. Additional wetland means any natural wetland or any converted wetland that has reverted to wetland as the result of abandonment of crop production. Abandonment is the cessation of cropping, management maintenance operations related to the production of agricultural commodities on converted wetland. Where the cessation of such cropping, management or maintenance operations has occurred, converted wetland is considered to be abandoned unless it is shown that there was no intent to abandon; provided, however, that at the end of five successive years during which there was no crop production, such land shall be determined to be abandoned if the land meets the wetland criteria of § 12.31. Participation in a USDA set-aside, diverted acres, or similar programs shall not be deemed to constitute abandonment.

or

(a) The term "department" means one of the executive departments enumerated in section 1 of Title 5, United States Code.

(b) The term "agency" includes any department, establishment, commission, administration, authority, board, bureau, or service of the United States, or any corporation all of the capital stock of which is owned by the United States.

(c) The term "CCC" means Commodity Credit Corporation, U.S. Department of Agriculture.

(d) The term "ASCS" means the Agricultural Stabilization and Conservation Service, U.S. Department of Agriculture.

(e) The term "withholding" means the taking of action temporarily to prevent the payment of a specified amount from amounts payable to a debtor.

(f) The term "setoff" means the application of a specified amount from amounts payable to a debtor as liqui