DWQ-2023-200045

APPENDIX I.A - Storm Water Discharges Associated with Industrial Activity from Timber Products Facilities
Coverage of This Section.
Discharges Covered Under This Section. The requirements listed under this Part shall apply to storm water discharges from the following activities:
Table I.A.1 – Sector A: Timber Products
SIC Code
Activity Represented
2411
Log Storage and Handling
2421
General Sawmills and Planning Mills
2426
Hardwood Dimension and Flooring Mills
2429
Special Product Sawmills, Not Elsewhere Classified
2431 – 2439
(except 2434)
Millwork, Veneer, Plywood, and Structural Wood
(See Sector W for Wood Kitchen Cabinet Manufacturers (SIC 2434))
2441
Nailed and Lock Corner Wood Boxes and Shook
2448
Wood Pallets and Skids
2449
Wood Containers, Not Elsewhere Classified
2451, 2452
Wood Buildings and Mobile Homes
2491
Wood Preserving
2493
Reconstituted Wood Products
2499
Wood Products, Not Elsewhere Classified
Sector Specific Limitations on Coverage. In addition to the limitations on coverage listed in Part I.C, the following storm water discharges associated with industrial activity are not
authorized by this permit:
Discharges from areas where there may be contact with the chemical formulations sprayed to provide surface protection. These discharges must be covered by a separate UPDES permit.
Stormwater discharges from earth-disturbing activities. These are considered construction activities and must be covered under the UPDES Storm Water General Permit for Construction Activity,
General Permit Number UTRC00000.
Sector Specific Prohibition of Non-Stormwater Discharges. In addition to those non-storm water discharges prohibited under Part I.D.2, this permit does not authorize the discharge of:
Discharges of boiler blowdown and water treatment wastewaters, noncontact and contact cooling waters, wash down waters from treatment equipment, and storm water that has come in contact
with areas where spraying of chemical formulations designed to provide surface protection, to waters of the State, or through municipal separate storm sewer systems. The operators of
such discharges must obtain coverage under a separate UPDES discharge permit.
Sector Specific Control Measures and Effluent Limits.
In addition to the control measures and effluent limits in Part III, the permittee shall implement the following to minimize pollutant discharges, as applicable:
Good Housekeeping. In addition to the requirements in Part III.C, good housekeeping measures in storage areas, loading and unloading areas, and material handling areas shall be designed
to:
Limit the discharge of wood debris;
Minimize the leachate generated from decaying wood materials; and
Minimize the generation of dust.
Maintenance of Control Measures. In addition to the requirements in Part III.D, the maintenance of control measures shall include, at a minimum:
Periodic removal of debris from ditches, swales, diversions, containment basins, sediment ponds and infiltration measures should be performed to limit discharges of solids and to maintain
the effectiveness of the controls.
Spill Prevention and Response Procedures. In addition to the requirements in Part III.E, the spill prevention and response procedures shall address the following, at a minimum:
Leaks or spills of wood surface protection or preservation chemicals shall be cleaned up immediately in accordance with applicable Resource Conservation and Recovery Act (RCRA) regulations
at 40 CFR Part 264 and 40 CFR Part 265.
Sector Specific Inspection Requirements.
In addition to the inspection requirements in Part IV.A, the permittee shall also inspect the following activities, if they take place at the facility:
Wood Surface Protection and Preservation. If the facility performs wood surface protection and preservation activities, the permittee shall inspect the following areasat least monthly
to assess the usefulness of practices to minimize the deposit of treatment chemicals on unprotected soils in areas that will come in contact with stormwater discharges:
Processing areas;
Transport areas; and

Treated wood storage areas.
Sector Specific Plan Requirements.
Site Map. In addition to the requirements in Part VII.D.3, the site map shall also include the location of the following, if applicable:
Treatment chemical and equipment storage areas;
Treated and untreated wood and residue storage areas; and
Wet and dry decking areas.
Summary of Potential Pollutant Sources. In addition to the requirements in Part VII.D.4, the Plan summary of potential pollutant sources shall also include the following, as applicable:
Where information is available, facilities that have used chlorophenolic, creosote, or chromium-copper-arsenic formulations for wood surface protection or wood preserving activities
in the past shall identify:
Areas where contaminated soils, treatment equipment, and stored materials still remain; and
Management practices employed to minimize the contact of these materials with stormwater.
Measures and Controls. In addition to the requirements in Part VII.D.5, the Plan shall also include measures implemented to address the following activities and sources, as applicable:
Log, lumber, and wood product storage areas;
Residue storage areas;
Loading and unloading areas;
Material handling areas;
Chemical storage areas; and
Equipment and vehicle maintenance, storage, and repair areas.
If the facility performs wood surface protection and preservation activities, the Plan shall address the specific controls measures, including any BMPs, for these activities.
Monitoring Requirements.
Analytical Benchmark Monitoring. The following analytical benchmark monitoring parameters shall apply specifically to sector A facilities. Parameters found in this Part apply to both
primary industrial activities and any co-located industrial activities. The facility may be subject to the requirements of more than one of the following:
Table I.A.2 – Analytical Benchmark Monitoring Parameters for Log Storage and Handling (SIC 2411)
Parameter
Benchmark Monitoring Concentration
Total Suspended Solids1
100 mg/L
Sampling for total suspended solids is not required for stormwater discharges that are infiltrating to groundwater.
Table I.A.3 – Analytical Benchmark Monitoring Parameters for General Sawmills and Planning Mills (SIC 2421)
Parameter
Benchmark Monitoring Concentration
Chemical Oxygen Demand
120 mg/L
Total Suspended Solids 1
100 mg/L
Total Recoverable Zinc (freshwater)
Hardness Dependent 2
Total Recoverable Zinc (saltwater)3
0.090 mg/L
Sampling for total suspended solids is not required for stormwater discharges that are infiltrating to groundwater.
The freshwater analytical benchmark monitoring values of some metals are dependent on water hardness. For these parameters, permittees must determine the hardness of the receiving water
to identify the applicable ‘hardness range’ for determining the analytical benchmark monitoring value applicable to the facility. Hardness dependent analytical benchmark monitoring shall
follow the table below:
Freshwater Hardness Range
Zinc (mg/L)
0.00 – 24.99 mg/L
0.037
25 – 24.99 mg/L
0.052
50 – 74.99 mg/L
0.080
75 – 99.99 mg/L
0.107
100 – 124.99 mg/L
0.132
125 – 149.99 mg/L
0.157
150 – 174.99 mg/L
0.181
175 – 199.99 mg/L

0.204
200 – 224.99 mg/L
0.227
225 – 249.99 mg/L
0.249
250+ mg/L
0.260
If hardness cannot be determined (groundwater or inaccessible waterbodies), use the most conservative values (0-24.99 mg/L range).
Saltwater benchmark values apply to stormwater discharges into saline waters where indicated.
Table I.A.4 – Analytical Benchmark Monitoring Parameters for Wood Preserving Facilities (SIC 2491)
Parameter
Benchmark Monitoring Concentration
Total Recoverable Arsenic (freshwater)
0.150 mg/L
Total Recoverable Arsenic (saltwater) 1
0.069 mg/L
Total Recoverable Copper (freshwater)
0.00519 mg/L
Total Recoverable Copper (saltwater) 1
0.0048 mg/L
Saltwater benchmark values apply to stormwater discharges into saline waters where indicated.
Table I.A.5 – Analytical Benchmark Monitoring Parameters for Hardwood Dimension and Flooring Mills (SIC 2426); Special Products Sawmills, not elsewhere classified (SIC 2429); Millwork,
Veneer, Plywood and Structural Wood (SIC 2431-2439, except 2434); Nailed and Lock Corner Wood Boxes and Shook (SIC 2441); Wood Containers (SIC 2449); Wood Buildings and Mobile Homes
(SIC 2451, 2452); Reconstituted Wood Products (SIC 2493); and Wood Products Facilities not elsewhere classified (SIC 2499)
Parameter
Benchmark Monitoring Concentration
Chemical Oxygen Demand
120 mg/L
Total Suspended Solids 1
100 mg/L
Sampling for total suspended solids is not required for stormwater discharges that are infiltrating to groundwater.
Numeric Effluent Limitation Monitoring. Numeric effluent limitation monitoring shall be required for sector A facilities conducting certain industrial activities. The concentration of
pollutants in stormwater discharges, independent of comingling, as discussed in Part V.C.2, shall not exceed the following effluent limitations at any time during the duration of permit
coverage.
Table I.A.6 – Numeric Effluent Limitation Monitoring Parameters
Industrial Activity
Parameter
Effluent Limitation
Discharges resulting from spray down or intentional wetting of logs at wet deck storage areas
pH
6.0 – 9.0 s.u.
Debris (woody material such as bark, twigs, branches, heartwood, or sapwood)
No discharge of debris that will not pass through a 2.54cm (1-in.) diameter round opening