Glass-Clay-Cement-Concrete-Gypsum Products Sector - SWPPP - Stormwater Permit Proposed Requirements

On July 6, 2009, the Minnesota Pollution Control Agency released its proposed multisector industrial stormwater discharge general permit. This permit, once promulgated, will replace the existing industrial stormwater permit, which expired in October of 2002.

[Read a summary of the overall Minnesota permit, stormwater monitoring, and sector requirements]

Caltha LLP will be conducted seminars on the proposed sector requirements in July & August 2009. Caltha MPCA Industrial Stormwater Permit Requirements Seminars

The proposed permit details requirements for 29 different industrial sectors. The requirements described below are proposed for the Glass, Clay, Cement, Concrete, and Gypsum Products Sector (Sector E). Sector E covers a fairly broad range of product types, including flat glass, glass containers, pressed and blown glass, hydraulic cement, structural clay products, pottery and related products, concrete, gypsum, and plaster products, glass products, cut stone and stone products, abrasives, asbestos products, and miscellaneous non metal mineral products, mineral wool and mineral wool insulation products, and non-clay refractories. These requirements are in addition to permit requirements that apply to all sectors.

Inspections:
The facility must conduct inspections of dust collection and containment systems.

Good Housekeeping:
The facility must prevent or minimize the discharge of spilled cement, aggregate (including sand or gravel), kiln dust, fly ash, or settled dust from paved portions of the facility that are exposed to stormwater. Each facility must determine the frequency of sweeping or equivalent by the amount of industrial activity occurring in the area and the frequency of exposure to stormwater, but it must be performed at least once a week, if cement, aggregate, kiln dust, fly ash, or settled dust are being handled or processed. The operation must also prevent the exposure of fine granular solids (cement, fly ash, kiln dust, etc.) to stormwater.

Preventative Maintenance:
For facilities producing ready-mix concrete, concrete block, brick, or similar products preventive measures must be implemented that ensure that process wastewater resulting from washing trucks, mixers, transport buckets, forms, or other equipment are discharged in accordance with a separate applicable NPDES permit..

Stormwater Monitoring Benchmarks:
All facilities are required to conduct visual and chemical (benchmark) monitoring. For benchmark monitoring, the benchmark concentrations or values depend on product type:

Clay Products Manufacturers (SIC 3251-3259, 3261-3269):
Total Aluminum 1.5 mg/L
TSS 100 mg/L

Concrete and Gypsum Product Manufacturers (SIC 3271-3275):
TSS 100 mg/L
Total Iron 1.0 mg/L

Cement Manufacturing Facility, Material Storage Runoff:
TSS 100 mg/L
pH 6 - 9

Others:
TSS 100 mg/L

Note: Benchmark for aluminum were derived based on the Aquatic Life Standards for these parameters in Minnesota Rules.

[Read more about use of Aquatic Life Standards to derive stormwater benchmarks]
[Read more about how benchmarks are used under the proposed MPCA industrial permit]
[Read more about what a 100 mg/L benchmark for TSS relates to]


Looking for other sector information? Click here for a link to all sector requirements

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address Stormwater Permitting & Regulatory Support, Stormwater Pollution Prevention Plans (SWPPP), Stormwater Monitoring and Stormwater Training.

For further information contact Caltha LLP at
info@calthacompany.com
or
Caltha LLP Website