Iowa Administrative Code › Agency 567 - Environmental Protection Commission › Title IV - Wastewater Treatment and Disposal › Chapter 65 - Animal Feeding Operations › Rule 567-65.206 - Settled Open Feedlot Effluent Basins-investigation, Design and Construction Requirements

Current through Register Vol. 47, No. 3, July 24, 2024
A settled open feedlot effluent basin required to be
				  constructed pursuant to a construction permit issued pursuant to Iowa Code
				  section 459A.205 shall meet the design
				  and construction requirements set forth in this rule.
(1)
Drainage tile investigation and
				removal.
Prior to constructing a settled open feedlot effluent basin,
				the site for the basin shall be investigated for drainage tile lines as
				provided in this subrule. All applicable records of known drainage tiles shall
				be examined for the existence of drainage tile lines. Prior to the excavation
				for an unformed manure storage structure, an inspection trench of at least ten
				inches wide shall be dug around the structure to a depth of at least 6 feet
				below the original grade and within 25 feet of the proposed outside of the toe
				of the berm. Drainage tile lines discovered during the tile inspection of a
				settled open feedlot effluent basin shall be removed and rerouted in the
				inspection trench or in an area outside of the inspection trench. All tiles
				within the inspection trench perimeter shall be removed or completely plugged
				with concrete, grout or similar materials. Drainage tile lines installed at the
				time of construction to lower the groundwater may remain in place as long as
				they are outside of the proposed toe of the berm.
(2)
Soils and hydrogeologic
				report.
A settled open feedlot effluent basin required to be
				constructed pursuant to a construction permit issued pursuant to rule
				567-65.203(455B,459A) shall meet design standards as required by a soils and
				hydrogeologic report. The report shall be submitted with the construction
				permit application as provided in rule
				567-65.204 (455B,459A). The
				report shall include all of the following:
a.
				A description of the steps taken to determine the soils and hydrogeologic
				conditions at the proposed construction site, a description of the geologic
				units encountered, and a description of the effects of the soil and groundwater
				elevation and direction of flow on the construction and operation of the
				basin.
b. The subsurface soil
				classification of the site. A subsurface soil classification shall be based on
				ASTM international designation D 2487-06 or D 2488-06.
c. The results of a soils investigation
				conducted at a minimum of three locations within the area of the basin
				reflecting the continuous soil profile existing within the area of the basin.
				The soils investigation results shall be used in determining subsurface soil
				characteristics and groundwater elevation and direction of flow at the proposed
				site. The soils investigation shall be conducted and utilized as follows:
(1) By a qualified person ordinarily engaged
				in the practice of performing soils investigations.
(2) At locations that reflect the continuous
				soil profile conditions existing within the area of the proposed basin,
				including conditions found near the corners and the deepest point of the
				proposed basin. The soils investigation shall be conducted to a minimum depth
				of ten feet below the proposed bottom elevation of the basin.
(3) By methods that identify the continuous
				soil profile and do not result in mixing of soil layers. Soil corings using
				hollow stem augers and other suitable methods that do not result in soil layer
				mixing may be used.
(4) Soil
				corings may be used to determine current groundwater levels by completing the
				corings as temporary monitoring wells as provided in subparagraph
				65.206(3)
"a"
(1) and measuring the water levels in these wells
				no earlier than seven days after installation as provided in subparagraph
				65.206(3)
"a"
(2).
(5) Upon abandonment of soil core holes, all
				soil core holes including those developed as temporary water level monitoring
				wells shall be plugged with concrete, Portland cement concrete grout,
				bentonite, or similar materials.
(6) If excavation methods are used in
				conducting the soils investigation, upon closure these excavations must be
				filled with suitable materials and adequately compacted to ensure they will not
				compromise the integrity of the basin liner.