N.H. Code Admin. R. Env-Ws 382.23

Current through Register No. 25, June 20, 2024

Section Env-Ws 382.23 - Enhanced Coagulation and Enhanced Softening Step 1 Performance Requirements

(a) A system owner shall achieve the percent reduction of TOC specified in Table 382-3:

Table 382-3

STEP 1 REQUIRED REMOVAL OF TOC BY ENHANCED COAGULATION

AND ENHANCED SOFTENING FOR SW/GWUDISW SYSTEMS

USING CONVENTIONAL TREATMENT

Source-water TOC, mg/L	Source-water alkalinity, mg/L as CaCO3
	0-60	61 - 120	Greater than 120
Greater than 2.0-4.0	35.0%	25.0%	15.0%
Greater than 4.0-8.0	45.0%	35.0%	25.0%
Greater than 8.0	50.0%	40.0%	30.0%

(b) The Step 1 TOC reductions specified in (a), above shall be:

(1) Achieved between the source water and the combined filter effluent; and

(2) Based upon specified source water parameters measured in accordance with Env-Ws 382.06(g).

(c) A system owner unable to comply with Step 1 TOC reductions in (b)(1), above, may submit to the department a written request for approval of the alternative Step 2 TOC reduction specified in (f) below.

(d) The written request shall include the following information:

(1) The system name;

(2) The system EPA identification number; and

(3) The most recent bench- or pilot-scale study.

(e) The department shall approve the request if the bench or pilot test study concludes that the system is unable to meet Step 1 TOC removal requirements.

(f) A system owner practicing softening shall meet the step 1 TOC reductions in the Source Water Alkalinity Greater than 120 mg/L column of Table 382-3 for the specified source water TOC.

(g) A system owner meeting at least one of the conditions specified in Env-Ws 382.22(b) shall not be required to operate with enhanced coagulation.

(h) A softening system meeting one of the alternative compliance criteria in Env-Ws 382.22(f) shall not be required to operate with enhanced softening.

(i) The owner of a SW/GWUDISW system owner using conventional treatment that cannot achieve the Step 1 TOC removals required by (a) above, due to water quality parameters or operational constraints, shall submit a written request to the department, within 3 months of the failure to achieve the TOC removals, for approval by the department of alternative minimum TOC, Step 2, removal requirements.

(j) The request shall include the items specified in Env-Ws 382.24(b).

(k) The department shall approve the request if the bench or pilot test study concludes that the system is unable to meet Step 1 TOC removal requirements.

(l) If the department approves the alternative minimum TOC removal, Step 2, requirements, the department shall make those requirements retroactive for the purposes of determining compliance provided the requirements of Env-Ws 382.20(b) and (c) are met. Until the department approves the alternate minimum TOC removal, step 2, requirements, the system shall meet the step 1 TOC removal requirements contained in (a) above.

N.H. Code Admin. R. Env-Ws 382.23

(See third Revision Note at chapter heading Env-Ws 300); #7735, eff 8-2-02; amd by #8351, eff 5-14-05