1 Dust Ash Manufacturing Inc is located along the Blugreen

1. Dust & Ash Manufacturing, Inc. is located along the Blugreen River in the city of Northgrove. The company discharges suspended solids, pH, and Biochemical Oxygen Demand (BOD) directly from a pipe into the river and discharges its sewage into the Northgrove municipal sewage treatment plant, a Publicly Owned Treatment Works. a. What kind of permit would Dust & Ash Manufacturing need to legally discharge to the Blugreen River? What types of requirements would be included in that permit? (15 points) b. Describe the Clean Water Act requirements, if any, that allow Dust & Ash Manufacturing to legally discharge to the sewage treatment plant. (7 points)

Solution

a) This answer follows the guidelines of \"National Pollutant Discharge Elimination System (NPDES)\" designed by \"United States Environmental Protection Agency\". A permit is a licenece granted by government which gives permission to discharge waste water in streams. As per code, there are two types of permits, namely general permit & individual permits.

Based on the question, manufacturing industries should apply for individual permit for each pollutant like suspended solids , pH & BOD. The component for each permit should include:

1. Cover page: This includes the name & location of permitte, location where discharge is autorized & a statement seeking permission to discharge.

2. Effluent Limitations: This point should include the primary mechanism used by the industry for controlling discharges of pollutants to receiving waters & defining appropriate effluent limitations on the basis of applicable technology and water quality standards.

3. Monitoring and Reporting Requirements: In this step, the overall efficiency of removal of pollutant is calculated & should be compared with quality standards which are used to characterize wastestreams and receiving waters.

4. Special Conditions: Here conditions developed to supplement numeric effluent limitations are explained thoroughly. For example, Best management practices, pollution prvention, additional monitoring activities, special studies & compliance schedules.

5.Standard Conditions: Pre-established conditions that apply to all NPDES permits.

Apart from the above mentioned points, these are some adittional points that one has to clearly mention,

b) As per the clean water act, industry has to limit the concentration of pollutants within the safe limits proposed by clean water act. The safe limits of each pollutant depends on the technology used for treating waste water & broadly classified as:

1.Secondary Treatment Standards  

2. Equivalent to Secondary Treatment Standards  

The safe limits are mentioned in table shown below,

Table 1: Secondary treatment standards

Table 2: Equivalent to secondary treatment standards

Parameter	7- day average	30- day average
BOD	45 mg/L	30 mg/L
Suspended solids	45 mg/L	30 mg /L
pH	6-9	6-9
BOD5 and TSS removal (concentration)	85%	-