SAN JOAQUIN VALLEY UNIFIED AIR POLLUTION CONTROL DISTRICT

RULE 7060 - TOXIC METALS FROM NON-FERROUS METAL MELTING
(Adopted December 15, 1994)

1.0 Purpose

The purpose of this rule is to control airborne emissions of toxic metals from non-ferrous metal melting. Compliance schedule, recordkeeping, and test methods are specified. This rule incorporates provisions of California Code of Regulations Section 93107.

2.0 Applicability

The provisions of this rule shall apply to existing non-ferrous metal melting furnaces.

3.0 Definitions

For the purpose of this rule, the following definitions shall apply:

4.0 Exemptions

Table 1

Metal

Exemption Limit

(tons per year)

Pure Lead

400

Hard Lead

200

Aluminum Scrap

125

Aluminum Ingot containing more than 0.004% cadmium or 0.002% arsenic

125

Solder

100

Zinc Scrap

30

Copper or copper based alloys (except scrap) containing more than

0.004% cadmium or 0.002% arsenic

30

Type Metal (lead for linotype machines)

25

5.0 Requirements

No person shall operate a non-ferrous metal melting furnace unless the facility is in compliance with all the requirements specified in subsections 5.1 through 5.3.

6.0 Administrative Requirements

7.0 Compliance Schedule

8.0 Alternative Compliance Option

The APCO may approve an alternative approach to compliance, proposed by the facility operator, if the facility operator demonstrates to the satisfaction of the APCO that the alternative is enforceable, achieves the same or better reductions in emissions and risk, and achieves these reductions within the same time period as required by this airborne toxic control measure. The alternative approach shall also be consistent with the Federal Clean Air Act. The APCO shall revoke this approval if the facility operator fails to adequately implement the alternative approach or the alternative approach does not reduce emissions as required. The APCO shall notify the state board whenever it proposes to approve an alternative approach for compliance with this airborne toxic control measure.


Attachment 1

Digestion of Metal Aluminum Sample for Determining As

  1. Introduction

    Metal Aluminum cannot react with nitric acid or concentrated sulfuric acid. It can dissolve in dilute sulfuric acid or hydrochloric acid. Active hydrogen, generated during the acid digestion process, will reduce arsenic to AsH3, which will escape from solution, resulting in a low or negative arsenic value. The proposed method sets up a protocol to dissolve metal alumina without loss of arsenic.

  2. Reagent

        3M NaOH, 10% HgSO4 Solution, 30% H2O2

        1:1 H2SO4, Concentrated HNO3, Tiling Copper

  3. Procedure

    3.1 Dissolve

      3.1.1 Dissolve using NaOH (Method 1)

      Weigh 0.5g of metal Aluminum sample to a 125 ml Erlenmeyer flask, add 15 ml of 3M NaOH solution, allow to react and dissolve about 20 min. Again add 10 ml of 3M NaOH, continue reaction until no gas bubbles are present and the sample is dissolved completely.

      3.1.2 Dissolve using HgSO4 (Method 2)

      Weigh 0.5g of metal Aluminum sample to a 125 ml Erlenmeyer flask, add 10 ml of 10% HgSO4 solution and 5 ml of 30% H2O2. After 20 min, add appropriate amount of HgSO4. Allow reaction to continue until no gas bubbles are present. Add metal copper strips (large surface area) into the sample solution. After 10 min, withdraw the copper strips and add new copper strips. Repeat until the surface of the copper strips in sample solution do not change to silver color. Withdraw all copper strips from sample solution.

    3.2 Digestion

    Add 3 ml of concentrated HNO3, 5 ml of 1:1 H2SO4 into the sample solution obtained from 3.1.1 or 3.1.2. Heat slowly and evaporate the sample solution until SO3 fumes are present for 5 min. Cool and dilute the sample to 50.0 ml.

    Determine As by Atomic Absorption Method.