SECTION 252:606-8-6. Land application of biosolids

(a)   Compliance. All permittees shall operate a land application site pursuant to the terms of the DEQ issued permit and DEQ approved sludge management plan.

(b)   Requirements.

(1)   Certification. When required by the DEQ, the owner, generator or operator must certify that the land application system will be operated according to this Chapter.

(2)   One applier. A land application site shall be used by only one land applier at a time unless the DEQ approves other users.

(3)   Subsequent use for land application. The DEQ may approve a previously used land application site for subsequent land application.

(4)   Multiple sources. A land applier who owns or operates more than one source facility or surface impoundment may utilize the same land application site for the application of biosolids from the multiple facilities or impoundments with prior written approval of the DEQ.

(5)   Topography. A land application site must have minimal slope or be contoured to prevent ponding and soil erosion. No application can occur on land having a slope exceeding five percent (5%) but less than ten percent (10%) unless erosion or runoff controls are implemented for liquid biosolids. Land having a slope greater than ten percent (10%) may be utilized for land application of dewatered and dried biosolids only with DEQ approval.

(6)   Off-site hauling. The owner, generator or operator must prevent biosolids and mud from a land application site from being carried off-site. If necessary, biosolids hauling vehicles must be cleaned prior to leaving the site and the rinse water disposed of in accordance with DEQ rules.

(7)   Manner. Land apply sludge in a manner to prevent surface runoff and to control objectionable odors. Incorporate sludge into the soil before the end of each working day. Do not store or land apply, or allow to run off, sludge or wastewater to wetlands or waters of the state. Discharges to waters of the state are prohibited without a discharge permit under OAC 252:606.

(8)   pH limits. Any site with soil having a natural pH of less than 5.5 cannot be used for the land application of biosolids unless the soil pH is amended prior to application of biosolids. Documentation of soil amendment must be placed in the land applier's compliance records.

(9)   Phosphorus and nitrogen. Annual biosolids land application rate cannot exceed nitrogen and phosphorus rates for the crop grown and cannot be applied in rates that result in phytotoxicity.

(10)   Soil sampling.

(A)   Sample and analysis. All background and annual soil sampling and analyses must be of a composite sample taken from an area 80 acres or less in size for each site proposed or used for the land application of biosolids. The DEQ may approve larger sampling areas on a case by case basis. Soil testing procedures applicable for use in the local area in accordance with Oklahoma State University soil testing guidance or the local NRCS may be used.

(B)   Operational soil monitoring. A land applier must collect representative soil samples and have them analyzed as follows:

(i)   For soil pH and the nutrients - nitrogen (N), ammonia (NH4), nitrates (NO3), potassium (K) and phosphorus (P) prior to the next annual application of biosolids;

(ii)   For metals in Table 3 of 40 CFR § 503.13(b) after every third year of use prior to the fourth year of use; and

(iii)   For all required background metals prior to the fourth year of biosolids application on each site.

(11)   Laboratory analyses.

(A)   All biosolids analyses required by this Subchapter must be performed by an accredited laboratory.

(B)   All soil analyses performed under 606-8-6(b)(10)(B)(i) must be performed by an accredited laboratory or by a university laboratory that demonstrates to the reasonable satisfaction of the DEQ to have the analytical expertise and be familiar with Oklahoma crops and soils.

(12)   Monitoring wells. The DEQ may require monitor wells and boreholes in connection with the land application of biosolids. These wells must be designed, constructed and plugged in accordance with OAC 785:35.

(c)   Restrictions.

(1)   Weather. Do not land apply when the ground is frozen or saturated.

(2)   Endangered or threatened species. Land application cannot occur if it is likely to adversely affect a threatened or endangered species listed under Section 4 of the federal Endangered Species Act, 16 U.S.C. 1533(c), or the critical habitat of such species.

(3)   Metal and selenium concentration limits. A land applier must notify the DEQ by telephone within 24 hours and follow up with a written report if the metal or selenium concentrations exceed those in 40 CFR § 503.13(b)(3) (Table 3) or risk the revocation of the land application permit. Municipal biosolids that exceed the metal or selenium concentration limits set forth in 40 CFR, § 503.13(b)(1) (Table 1) cannot be land applied, but may be:

(A)   incinerated at an incinerator permitted by the DEQ; or

(B)   disposed at a solid waste landfill permitted by the DEQ for such waste disposal. Any biosolids disposed in a landfill must meet the pathogen and vector reduction requirements of this Subchapter.

(4)   Heavy Metals. The DEQ shall not approve the land application of biosolids that contains heavy metals above the concentration ranges normal to biosolids or sludges with a demonstrated effectiveness on Oklahoma soils, unless the permittee provides a study on the effects of the biosolids on a variety of Oklahoma soils and crops found at the location of the proposed land application site. Said study shall:

(A)   be conducted by a qualified research institute familiar with crops and soils in Oklahoma and approved by the DEQ;

(B)   be included with the sludge management plan; and

(C)   demonstrate the effect of the sludge during four (4) growing seasons.

(5)   Biosolids generated outside the State of Oklahoma. For municipal biosolids, whether Class A or Class B generated outside the State of Oklahoma, the biosolids produced shall meet all federal and state statutory requirements and the DEQ shall receive and approve test results demonstrating the quality of the biosolids, including samples of each load of biosolids performed by an independent laboratory approved by the DEQ and an agreement that the DEQ may perform random quality assurance sampling at the site of the generation of the biosolids prior to any biosolids coming into the State of Oklahoma.

(6)   Karst soils. The use of land application sites that overlie areas subject to karstification (i.e. sink holes or underground streams generally occurring in areas underlain by limestone, gypsum or dolomite), is prohibited, unless approved by the DEQ.

[Source: Added at 26 Ok Reg 1901, eff 7-1-09; Amended at 32 Ok Reg 977, eff 9-15-15]