La. Admin. Code tit. 43 § XV-5425

Current through Register Vol. 50, No. 11, November 20, 2024

Section XV-5425 - Revegetation: Standards for Success-Post-Mining Land Use of Wildlife Habitat

A. Introduction

1. This Section describes the criteria and procedures for determining ground cover and stocking success for areas developed for wildlife habitat.

2. Pursuant to §5423, ground cover and stocking success on wildlife habitat must be determined on the basis of the following conditions:

a. general revegetation requirements of the approved permit;

b. ground cover; and

c. tree or shrub stocking and survival.

3. The permittee is responsible for measuring and determining ground cover and stocking and submitting this data to the commissioner for evaluation. Procedures for making these determinations are described below.

B. Success Standards and Measurement Frequency

1. Ground Cover

a. Ground cover shall be considered acceptable if it has at least 70 percent density with a 90 percent statistical confidence for the last year of the five-year responsibility period.

b. The aggregate of areas with less than 70 percent ground cover must not exceed five percent of the release area. These individual areas must not be larger than 1 acre and must be completely surrounded by desirable vegetation that has a ground cover of not less than 70 percent. Areas void of desirable vegetation may not be larger than 1/4 acre and must be surrounded by desirable vegetation that has a ground cover of not less than 70 percent.

c. No more than 35 percent of the stand can consist of approved species not listed in the permit.

2. Tree and Shrub Stocking Rate

a. The stocking rate for trees and shrubs shall be determined on a permit-specific basis after consultation and approval by the Louisiana Department of Wildlife and Fisheries. Trees and shrubs that will be used in determining the success of stocking and the adequacy of the plant arrangement shall have utility for the approved post-mining land use. When this requirement is met and acceptable ground cover is achieved, the five-year responsibility period shall begin.

b. Tree and shrub stocking rate shall be sampled once during the last year of the five-year responsibility period. The woody plants established on the revegetated site must be equal to or greater than 90 percent of the stocking rate approved in the permit with 90 percent statistical confidence. Trees and shrubs counted shall be healthy and in place for not less than two growing seasons. At the time of final bond release at least 80 percent of the trees and shrubs used to determine success shall have been in place for 60 percent of the applicable minimum period of responsibility. The permittee must provide documentation of this in the form of paid receipts, reclamation status reports, and normal correspondence.

C. Sampling Procedures

1. Random Sampling

a. To assure that the samples truly represent the vegetative characteristics of the whole release or reference area, the permittee must use methods that will provide:

i. a random selection of sampling sites;

ii. a sampling technique unaffected by the sampler's preference; and

iii. sufficient samples to represent the true mean of the vegetative characteristics.

b. Sampling points shall be randomly located by using a grid overlay on a map of the release or reference area and by choosing horizontal and vertical coordinates. Each sample point must fall within the release or reference area boundaries and be within an area having the vegetative cover type being measured. Additionally, if the release area does not consist of a single unit, at least one sample point must be measured in each noncontiguous unit.

c. The permittee shall notify the office 10 days prior to conducting sampling or other harvesting operations to allow regulatory personnel an opportunity to monitor the sampling procedures.

2. Sampling Techniques

a. Ground Cover. There are several approved methods for measuring ground cover. As stated at §5423. A 1, these are: pin method, point frame method and line intercept method. The first contact, or "hit," of vegetation shall be classified by species as acceptable or unacceptable as follows.

Acceptable	Unacceptable
Vegetation approved in permit	Vegetation not approved in permit
Dead vegetation or litter from acceptable species	Rock or bare ground
Acceptable-not approved in permit

i. Pin Method. In the pin method, a pinpoint is lowered to the ground. If vegetation is encountered, a hit is recorded. If bare ground is encountered, a miss is recorded. Sample locations are distributed randomly throughout the area to be measured. Percentage of cover is the number of hits divided by the total number of points sampled. Each randomly placed pin is considered one sample unit. An acceptable type of pin method would include recording each pin contact at 1-foot intervals along a 100-foot tape. Each randomly placed 100-foot tape would be considered one sample unit.

ii. Point Frame Method. In the point frame method, a group of pinpoints is lowered to the ground. If vegetation is encountered, a hit is recorded. If bare ground is encountered, a miss is recorded. Sample locations are distributed randomly throughout the area to be measured. Percentage of cover is the number of hits divided by the total number of points sampled. Each randomly placed frame is considered one sample unit.

iii. Line Intercept Method. The sampling unit is a tape at least 100 feet long that is stretched from a random starting point in a randomly selected direction. The procedure consists of recording the length of tape underlain by vegetation, then dividing by the total length of tape to obtain the percentage of cover. Each randomly located tape is considered one sampling unit.

b. Sampling Circles (Trees/Shrubs)

i. A sampling circle shall be a round area of known radius. The permittee shall establish a sampling circle at each randomly selected sampling point such that the center of the sampling circle is the random point. Permittee may draw the circle by attaching a string to a stake fixed at the random point and then sweeping the end of the string (tightly stretched) in a circle around the stake. The permittee shall count all living trees and shrubs within each of the sampling circles. In more mature tree/shrub areas, the stakes may need to be extended to elevate the string above the growth.

ii. To count as a living tree or shrub, the tree or shrub must be healthy and must have been in place for at least two years. At the time of liability release, 80 percent must have been in place for three years.

3. Sample Adequacy

a. Ground Cover Data

i. Data shall be collected using a multi-staged sampling procedure. During the first stage, an initial minimum number of samples is taken. Using this initial group and applying the formula below, determine the actual number of samples needed.

Click Here To View Image

where:

n = minimum number of samples needed;

t² = squared t-value from the T-Table;

s² = initial estimate of the variance of the release (or reference) area; and

(0.1x)² = the level of accuracy expressed as 10 percent of the average cover (note that this term is squared).

ii. If the formula reveals that the required number of samples have been taken, the initial sampling will satisfy the sampling requirements. If a greater number of samples is needed, additional samples must be taken (Stage Two Sampling), as specified by the formula, and n recalculated. This process shall be repeated until sample adequacy is met.

b. Sampling Circles (Trees/Shrubs) Data

Click Here To View Image

(the variance (s²) must be based on oven dry weight)

where:

n = minimum number of samples needed;

t² = squared t-value from the T-Table;

s² = initial estimate of the variance of the release (or reference) area; and

(0.1x)² = the level of accuracy expressed as 10 percent of the average weight (note that this term is squared).

D. Data Submission and Analysis

1. If the data shows that revegetation success has been met, the permittee shall submit the data to the commissioner for review. Ground cover or stocking for the release area will be considered successful when it has been measured with an acceptable method, has achieved sample adequacy, and where the average ground cover or stocking value is equal to or greater than the success standard.

2. When the data indicates that the average ground cover and/or tree and shrub average stocking density is insufficient, but close to the standards, the permittee may submit the data to the commissioner to determine if the revegetation is acceptable when statistically compared to the standards using a t-test at a 90-percent statistical confidence interval.

E. Maps

1. When a proposed reclamation Phase III release is submitted to the office, it must be accompanied by maps showing:

a. the location of the area covered by the proposed release;

b. the location of reference plots; and

c. all permit boundaries.

2. When data from a previously approved plan is submitted to the office, it must be accompanied by maps showing:

a. the location of each transect and sampling circle location;

b. the area covered by the sampling; and

c. all permit boundaries.

F. Mitigation Plan

1. Ground cover must be greater than or equal to 70 percent coverage and tree and shrub stocking must achieve the revegetation standards by the fifth year of the five-year responsibility period. If these standards are not achieved by this date, the permittee must submit a mitigation plan to the commissioner that includes the following:

a. a statement outlining the problem;

b. a discussion of what practices, beyond normal agronomic practices, the operator intends to use to enable the area to finally meet the release standards; and

c. a new Phase III release proposal.

2. If renovation, soil substitution, or any other practice that constitutes augmentation is employed, the five-year responsibility period shall restart after the mitigation plan is approved and the practices are completed.

La. Admin. Code tit. 43, § XV-5425

Promulgated by the Department of Natural Resources, Office of Conservation, LR 29:1500 (August 2003).

AUTHORITY NOTE: Promulgated in accordance with R.S. 30:901-932.